Modular Design Technique for an Adaptive Cooling and Daylighting Roof Aperture System

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Authors Moradnejad, Maryam

Publisher The University of Arizona.

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MODULAR DESIGN TECHNIQUE FOR AN ADAPTIVE COOLING AND DAYLIGHTING ROOF APERTURE SYSTEM by

Maryam Moradnejad

______Copyright © Maryam Moradnejad 2020

A Thesis Submitted to the Faculty of the

COLLEGE OF ARCHITECTURE, PLANNING AND LANDSCAPE ARCHITECTURE

In Partial Fulfillment of the Requirements

For the Degree of

MASTER OF SCIENCE ARCHITECTURE EMERGING BUILT TECHNOLOGIES

In the Graduate College

THE UNIVERSITY OF ARIZONA

2020 2

THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE

As members of the Master’s Committee, we certify that we have read the thesis prepared by: Maryam Moradnejad, titled: MODULAR DESIGN TECHNIQUE FOR AN ADAPTIVE COOLING AND DAYLIGHTING ROOF APERTURE SYSTEM

and recommend that it be accepted as fulfilling the thesis requirement for the Master’s Degree.

______Date: ______07/14/2020_ Aletheia Ida, PhD, Assoc. Prof., UA SoA

______Date: 7/15/2020 Susannah Dickinson, Assoc. Prof., UA SoA

______Date: ______7/15/20 Kerri Hickenbottom, PhD, Assist. Prof., UA CEE

______Date: ______7/15/20 Dorit Aviv, PhD, Assist. Prof., UPenn EBD

Final approval and acceptance of this thesis is contingent upon the candidate’s submission of the final copies of the thesis to the Graduate College.

I hereby certify that I have read this thesis prepared under my direction and recommend that it be accepted as fulfilling the Master’s requirement.

______Date: ______07/15/2020 Aletheia Ida, PhD, Assoc. Prof., UA SoA Master’s Thesis Committee Chair College of Architecture, Planning and Landscape Architecture 3

AKNOWLEDGEMENTS

This thesis would not have been possible without the care, guidance, and support, generously provided by my advisor, committee members, and family.

I would like to express the deepest appreciation for my advisor, Assoc. Prof. Aletheia Ida, who has been a constant source of inspiration with her deep vision and knowledge. This research gained a lot from her experience, guidance, and advice. I also thank her for her friendship and empathy.

I am thankful and pay my gratitude to my committee members, Susannah Dickinson, Kerri Hickenbottom, and Dorit Aviv for their valuable support, insightful feedback, and countless expertise. It has been an honor and a privilege to work with these brilliant faculties.

I am extending my special thanks to Dorit Aviv, who has been a source of creativity and knowledge from the very beginning of this research.

I would like to acknowledge the University of Arizona (UA) Office of Research Discovery and Innovation (ORDI) Accelerated Funding Support (AFS), and Microsoft Global Datacenter Engineering for their support that allowed me to conduct my research.

Also, I express my thanks to my mother and all of my family members for sharing their support and love throughout this way even from thousands of kilometers away.

Finally, to my caring, loving, and supportive husband, Danial: Thank you. Your encouragement, love, and patience when the times got rough are much appreciated. 4

DEDICATION

To my beloved ones;

Danial and,

My kind mom, brothers, sisters, and their families. 5

TABLE OF CONTENTS FIGURES ...... 7 TABLES ...... 9 ABSTRACT ...... 10 1. OVERVIEW and METHODOLOGY...... 12 2. LITERATURE REVIEW ...... 13 2.1. Hot-Arid Climates ...... 13 2.1.1. Consumption ...... 15 2.1.2. Water Resources ...... 17 2.2. Precedent Studies ...... 18 2.2.1. Windcatcher Technologies ...... 19 2.2.1.1. Form and Temporal Functions ...... 20 2.2.1.2. Spatial Functions ...... 23 2.2.1.3. Material Functions ...... 24 2.2.1.4. Integrated System Advancements ...... 25 2.2.2. Hydrogel Membranes ...... 28 3. DESIGN HYPOTHESIS...... 30 3.1. Multifunctional Adaptive Roof Aperture ...... 30 3.1.1. Evaporative downdraft Cooling ...... 30 3.1.2. Radiant Cooling ...... 31 3.1.3. Natural Daylighting...... 31 3.1.4. Water Conservation...... 31 4. DESIGN ANALYSIS ...... 33 4.1. Simulation Studies ...... 33 4.1.1. Downdraft Airflow Analysis ...... 33 4.1.2. Solar Radiation Analysis ...... 35 4.1.3. Daylighting Simulation ...... 37 4.2. Waffle Design Proposal ...... 39 5. MODULAR DESIGN TECHNIQUE ...... 40 5.1. Modular Design Proposal...... 40 5.1.1. Evaporative Downdraft Cooling ...... 42 5.1.2. Radiant Cooling ...... 44 5.1.3. Natural Daylighting...... 44 5.1.4. Water Collection ...... 45 6

5.2. Physical Modeling Studies ...... 45 6. CONCLUSION and FUTURE WORK ...... 47 APPENDIX ...... 49 REFERENCES: ...... 59

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FIGURES

Figure 1. Research and design framework ...... 12 Figure 2. Koppen climate classification map, dry or arid climates ...... 13 Figure 3. Annual hourly relative (%), Tucson Int’l Ap, AZ, U.S. (TMY III) ...... 14 Figure 4. Annual hourly dry bulb temperature (oC), Tucson Int’l Ap, AZ, U.S. (TMY III) ...... 14 Figure 5. Seasonal pyschrometric charts showing climate relations to the zone, Tucson Int’l Ap, AZ, U.S. (TMY III) ...... 15 Figure 6. Energy consumption ratios according to use patterns for national (U.S.), regional (Southwestern Mountain), and state (Arizona) sectors ...... 16 Figure 7. Average monthly illuminance (Global Horizontal, Diffuse Horizontal, and Direct Normal), Tucson Int’l Ap, AZ, U.S. (TMY III) ...... 16 Figure 8. The U.S. Geological Survey's (USGS) map of depletion shows the cumulative depletion of groundwater. The map depicts depletion over the time period of 1900 to 2008 ...... 17 Figure 9. Average annual precipitating in Arizona state map shows Tucson high rate in state..... 17 Figure 10. Bioclimatic chart and effective cooling strategies for Tucson ...... 18 Figure 11. Tucson annual psychrometric chart integrated by bioclimatic ...... 18 Figure 12. Windcatcher system aspects ...... 20 Figure 13. Different types of traditional windcatchers: (A) one-sided windcatchers in , ; (B) two-sided windcatchers in Yazd, Iran; (C) four-sided windcatchers in , Iran; (D) six- sided windcatchers in Yazd, Iran; (E) eight-sided windcatcher in Dowlat-Abad Garden, Yazd, Iran ; (F) cylindrical windcatcher in Dubai ...... 21 Figure 14. A cross section of a space demonstrating the function of a one-sided windcatcher due to pressure differential at daytime ...... 22 Figure 15. A cross section of a space demonstrating the function of a two-sided windcatcher due to buoyancy effect ...... 22 Figure 16. Integration of windcatchers with water canals as a medium of evaporative technique23 Figure 17. Cooling performance of windcatcher incorporated with underground water channel () ...... 23 Figure 18. A windcatcher in Yazd, Iran made of mud with mud plaster cover and reinforced by wood ...... 24 Figure 19. Schematic of Monodraught, a windcatcher that integrates a solar powered ...... 25 Figure 20. Advanced system integrated windcatchers at University of ...... 26 Figure 21. Internal and external views of hybrid windcatchers in Bluewater shopping mall ...... 26 Figure 22. Adaptive roof aperture prototype at Princeton University ...... 27 Figure 23. Hydrogel images: a) SEM at 1µm (left); and b) saturated gel at 10 cm (right) ...... 28 8

Figure 24. Climate responsive adaptive biopolymeric membrane environmental performance .... 28 Figure 25. Hydroceramic prototype ...... 29 Figure 26. Schematic diagram of multi-functional system: A) daytime (left); and B) nighttime (right) ...... 30 Figure 27. Schematic diagram shows the water recuperation cycle’s four steps ...... 32 Figure 28. Parametric iterations of CFD simulation based on height and neck position 34 Figure 29. CFD simulation model setup demonstrates inlet at top of chimney and the outlet on the wall of space below (left) with two evaluation planes (right) ...... 34 Figure 30. CFD results for 4-meter height chimney ...... 35 Figure 31. Solar radiation simulation results for iteration one (top), two (middle), and three (bottom) ...... 36 Figure 32. Daylighting study space typology of 1-meter height, 6-meter square underneath oculus...... 37 Figure 33. Physical test of hydrogel light transmission with light meter ...... 37 Figure 34. Daylighting renders shows light and bright spots from the windcatcher integrated with hydrogel at winter (A), spring (B) and summer (C) ...... 38 Figure 35. Daylighting analysis results ...... 39 Figure 36. Diagram of the proposed multi-functional waffle structure chimney ...... 40 Figure 37. Modular design process (top) and result of optimizing each parameter (bottom) ...... 41 Figure 38. Modular design of adaptive cooling and daylighting aperture ...... 42 Figure 39. Modular aperture with different size of opening ...... 42 Figure 40. The cross section of the system shows evaporative function through the modular design ...... 43 Figure 41. The axon view of hat structure ...... 43 Figure 42. The cross section of the system shows radiant cooling function through the modular design ...... 44 Figure 43. Render shows natural daylighting through the modular design ...... 45 Figure 44. Water collection cycle ...... 45 Figure 45. Digital fabrication methods for prototype modeling ...... 46 Figure 46. Diagram of the multi-functional thermodynamic system: day (left) and night (right) . 47 Figure 47. Different space typologies with unitized adaptive building modules ...... 48 Figure 48. Modular system adaptive functions based on interior building demands ...... 48 Figure 49. Modules’ adaptive functions in response to micro-climate forces: a) evaporative and radiant cooling (left); and b) natural ventilation and natural daylighting (right) ...... 48 9

TABLES Table 1. DBT and RH% values of Tucson, AZ ...... 14 Table 2. Annual total radiation for three iterations ...... 36

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ABSTRACT

Cooling and heating systems are a major source of energy consumption in residential and commercial buildings globally [1]. More than 60% of total building energy consumption is attributed to heating, ventilation, and air-conditioning (HVAC) [2]. Existing experience has shown that techniques with natural ventilation and evaporative-cooling provide excellent thermal comfort, together with very low energy consumption [3].

One of the oldest passive cooling strategies in use today is the windcatcher system [4]. This roof structure has openings toward the prevalent wind direction to catching the airflow for downdraft cooling. Also, the system’s function at night is like a chimney that pulls the interior space heat out. Windcatchers are typically made with masonry and materials that help the radiant cooling during the cold night of desert climate. The main objective of the windcatcher is to keep interior spaces at the proper static temperature while relying on dynamic outdoor wind forces.

The adaptive roof aperture is an advancement on prior windcatcher technologies to provide dynamic response to the external wind directions and patterns to modulate the thermodynamic functions. This system provides either downdraft airflow at daytime or nighttime radiation by changing its geometry [5]. Other prior research demonstrates the effectiveness of superporous polyelectrolyte hydrogels for water sorption and diffusion [6]. In addition, the hydrogel provides multifunctional environmental response for evaporative cooling, natural daylighting, and heat capacitance with radiative cooling because of the material structure and optical characteristics [7].

This research addresses the adaptive functionality for a windcatcher through integrating unique materials such as hydrogel and phase-change materials (PCMs) into modular units for localized adaptive response. These materials provide high heat capacitance and emissivity while also transmitting natural daylight. The proposed integration of the modular units into the windcatcher form will accommodate evaporative and radiant cooling, natural daylighting, and water recuperation [8]. Evaporative cooling is enabled for the daytime downdraft when the hot-dry airflow streams interface with a hydrogel membrane embedded at the top part of the windcatcher. During the night, the hydrogel membrane at top of the structure will remain unsaturated to assist stack-ventilation, night-flush cooling. The hydrogel membrane may also provide daylighting based on saturation states. A selection of modular units that have optimum sky-exposure incorporate PCMs to provide thermal storage during the day and radiative cooling at night. The project also explores the potential for rain-water harvesting through the overall geometry and form to provide the system’s required water. 11

Different environmental analyses were conducted to determine the optimum overall geometry. Solar radiation analyses were conducted with the Rhino-Grasshopper Ladybug plug-in to determine optimal material integration to increase the radiant cooling and decrease the heat exchange. The daylight analyses were conducted with Rhino-Grasshopper Honeybee plug-in to determine the amount of illumination based on the different saturation levels of the hydrogel. The solar radiation and daylight analysis were performed for three times of day (8 am, 12 pm, and 4 pm) at three times of the year (spring equinox, summer solstice, and winter solstice). The Computational (CFD) simulations were conducted to analyze airflow morphology through different spatial conditions. CFD simulations are performed with the Rhino-Grasshopper Butterfly plug-in accessing the OpenFOAM analysis platform. To identify the spatial factors affecting the airflow behavior through the unique geometry, parametric variations are defined for the windcatcher height and aperture diameters and placement. Initial results provide insight into the optimal relationships between windcatcher geometries for inducing adequate airflow for passive cooling and a self- shading geometry to gain less radiation during the day.

At the next step, within a computational design process, the modules all over the shape were designed for holding the thermal mass. During the design process of modules, the defined parameters such as depth of each module, distribution of them, and the opening size of each module for sky cooling were linked to the solar radiation analysis. All these processes were performed to prevent the thermal mass materials to gain high radiation during the day and being as much as possible exposed to the sky during night time.

Ultimately, the analyses were conducted again on the final geometry to determine the efficiency of the design proposal. The full-scale prototype will be built within a research group in Tucson, AZ to compare the simulation results and validate them. The information about illuminance, air velocity, temperature differentials, water harvesting, and moisture diffusion rates will provide insight into how the design will be successful for both energy and water conservation potentials. 12

1. OVERVIEW and METHODOLOGY

This research starts by a deep investigation of hot-arid climates to identify the characteristics of this climate type, its challenges and potentials, which could be utilized in the built environment. At the next step of literature review the research is developed by studying the precedent solutions and technologies within the built environment, which inform a need to adapt to the specific climate conditions. The integration of these studies is introduced as a multifunctional system that addresses adaptive environmental response. To evaluate the system performance under different environmental and spatial conditions, several analytical simulations and analyses were conducted. By extracting information from analyses several parameters were defined to design an optimum modular geometry that enhance the functionality of the system. The simulations result after applying design strategies demonstrate the function of the system. By fabrication of the full-scale prototype and conducting the physical tests, the information could be extracted to arrive at comparisons with simulation results and demonstrate the performance of the system for each function. Figure 1 shows the research framework and its three steps: literature review, design and analysis and results.

Figure 1. Research and design framework 13

2. LITERATURE REVIEW

2.1. Hot-Arid Climates

Hot-arid climates, (or as Koppen mentions it as dry or arid climates), are basically located between 20 and 33 north and south latitude and have special conditions of high temperature, dry weather and intense sunshine all over the year (Fig. 2) [9]. The Sonoran Desert is one of the hot-arid climate regions in Northern America, which has about 275000 km2 coverage including the southern region of Arizona and parts of northwestern Mexico [10]. Tucson is a metropolitan area located within the Sonoran Desert of Arizona and is recognized as one of the hot-arid urban climates of this region.

During the summer, in Sonoran Desert the temperature goes beyond 40°C (104°F), and often reaches 48°C (118°F). Also, in this area in all seasons there is an average diurnal temperature swing of 15°C, which can be exceeded during the hottest days of summer [11]. The monsoon, an extremely sudden and heavy rain, occurs in late summer between July 15th to early September. Moreover, the winter season is a short period between December and January when additional precipitation occurs. Annual precipitation in the Sonoran Desert averages from 76 to 500 mm (3– 20 in), which in Tucson is 12 inches [12].

Figure 2. Koppen climate classification map, dry or arid climates [13]

Like all hot-arid climate locations, Tucson has two significant features: high temperature and low humidity. The Typical Meteorological Year (TMY) III climate data for Tucson, Arizona provides more precise information about this area. The relative humidity (RH%) chart (Fig. 3) demonstrates the low amount of humidity throughout the year except the short time of monsoon season from the late June to end of August as well as a short period of winter time when precipitation occurs. In some days of summer, the relative humidity is less than 10%. Furthermore, the dry bulb temperature 14

(DBT) chart (Fig. 4) shows that Tucson experiences temperatures of higher than 30oC about all of the days for more than half of the year. It also shows that even during winter that has cold nights, the temperature is high at noon time. The diurnal temperature swing demonstrates the high variation between night and day temperature in this area. For a more precise study, the following examples provides DBT and RH% values for spring equinox, summer solstice, fall equinox, and winter solstice (Table 1).

Table 1. DBT and RH% values of Tucson, AZ

March 21st: 24.2 oC 10% RH June 21st: 37.2 oC 19% RH September 21st: 33.9 oC 27 % RH December 21st: 18.3 oC 33 % RH

Figure 3. Annual hourly relative humidity (%), Tucson Int’l Ap, AZ, U.S. (TMY III)

Figure 4. Annual hourly dry bulb temperature (oC), Tucson Int’l Ap, AZ, U.S. (TMY III)

Based on the definition from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 55-66, thermal comfort is the condition of mind which expresses satisfaction with the thermal environment and is based on six basic parameters. Air Temperature (°C), Mean Radiant Temperature (MRT), Relative Humidity (RH%), Air Velocity (v), Clothing Units (Clo), Metabolic Rate (Met) [14]. The following psychrometric charts shows each season thermal comfort condition. 15

Figure 5. Seasonal pyschrometric charts showing climate relations to the thermal comfort zone, Tucson Int’l Ap, AZ, U.S. (TMY III) High temperatures and humidity provide discomfort sensations. Humans generally feel comfortable between temperatures of 20°C to 25°C and a relative humidity of 20% to 80% (for most of year the range is between 40% to 60%). The seasonal pyschrometric charts of Tucson, AZ (Fig. 5) demonstrate that in the most of days of the year the condition is out of the comfort zone so it can be concluded that Tucson’s climate condition affects the human thermal comfort throughout the year.

2.1.1. Energy Consumption

The intense and harsh conditions of the hot-arid climate regions result in built environment challenges such as high energy consumption. Based on the United States Energy Information Administration (U.S. EIA), energy consumed by the residential and commercial buildings is 20% of global energy consumption [15]. The International energy outlook 2019 (IEO2019) reference case anticipates that global energy consumption in buildings will grow by 1.3% per year on average from 2018 to 2050 [16]. In 2018, 40% (or about 40 quadrillion British thermal units) of total U.S. energy consumption is by the residential and commercial building sector [15] .

There is significant use of for cooling buildings in hot-arid climates. This high demand of electricity use causes detrimental impacts on the environment, such as carbon emissions 16

and water resource depletion. Cooling and heating systems are typically the major source of energy consumption in residential and commercial buildings [17]. Existing research by EIA demonstrates that a quarter of the energy consumed in Arizona homes is for air conditioning, which is more than four times of the national average [15]. Furthermore, the chart below (Fig. 6) shows that 43% of whole energy consumption accounted for lighting that is again more than national average [15].

Figure 6. Energy consumption ratios according to use patterns for national (U.S.), regional (Southwestern Mountain), and state (Arizona) sectors [15]

On the other hand, the unique climate characteristics of this region provide some potentials that can be considered within the building design, such as reducing the electric lighting load because of the abundant daylighting options. For example, data from for Tucson’s TMY III illumination values (Fig. 7) demonstrates the intense illuminance available in this area throughout the year. The highest rate is for July month with 36000 lux and the lowest rate is related to Dec with about 2200 lux, which is still high. This high illumination is because of the mostly clear sky of Tucson.

Figure 7. Average monthly illuminance (Global Horizontal, Diffuse Horizontal, and Direct Normal), Tucson Int’l Ap, AZ, U.S. (TMY III) 17

2.1.2. Water Resources

According to the United States Geological Survey (USGS) research about water depletion in the U.S. shows that Arizona is in danger of severe water crisis [18]. On the other hand, reports from Arizona State Climate Office shows Tucson has high amount of precipitation during heavy monsoon rain season as well as winter rains [19], which provide opportunities of rainwater

harvesting.

Figure 8. The U.S. Geological Survey's (USGS) map of groundwater depletion shows the cumulative depletion of groundwater. The map depicts depletion over the time period of 1900 to 2008 [18]

Figure 9. Average annual precipitating in Arizona state map shows Tucson high rate in state [18] 18

2.2. Precedent Studies

For investigating passive design strategies that would be beneficial for human thermal comfort the bioclimatic chart is studied. The bioclimatic chart (Fig. 10), which utilizes the psychrometric chart as its basis, provides thermal design strategies based on analysis of climate data of a given location by considering the human comfort [20]. This chart determines cooling strategy design conditions to maximize indoor comfort by making the condition close to the comfort zone [21].

Figure 10. Bioclimatic chart and effective cooling strategies for Tucson, redrawn by author as adapted by B. Givoni and M. Milne [20]

Figure 11. Tucson annual psychrometric chart integrated by bioclimatic chart by B. Givoni and M. Milne, redrawn by author

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With comparing the annual pyschrometric chart of Tucson, AZ with bioclimatic chart (Fig. 11), the most effective passive strategies that maximize the indoor comfort are identified as: evaporative cooling, high thermal mass, and natural ventilation. One of the passive cooling building technologies that combines each of these three strategies is the windcatcher, as demonstrated by historic examples in the next section.

2.2.1. Windcatcher Technologies

Windcatcher is an historic natural ventilation system that originates from Middle East countries such as Iran, Iraq and Egypt [22]. This passive cooling strategy is a roof integrated structure, which has openings toward the prevailing wind direction to capture the air stream and direct it into channels inside of the windcatcher. The channels increase the speed of wind and help it to circulate more effectively into the interior building spaces. Typically, the windcatcher is made by materials that have high heat capacity (such as masonry and ) to prevent [23]. The system functions at night is like a chimney, which pulls the heat from the interior spaces upwards and exhausts the hot air to the outside [24]. As one of the leading pioneering natural ventilation techniques, windcatchers decrease energy consumption and thus operational costs [25]. The research by Bahadori et al confirms that using the windcatcher as a passive cooling system is more economical than active cooling systems with units [17]. However, the functionality of windcatchers is reliant on sufficient airflow streams. A study by Yaghubi, et al on three public buildings that operate windcatchers as ventilation demonstrates the functionality of all of the, even with low speed wind This research carries out the fact that windcatchers bring indoor thermal comfort by measuring temperature, relative humidity and airflow velocity after air circulation [24]. Based on the historic developments and advancements in windcatcher systems, the building technology has evolved from traditional static properties and functions with early construction techniques to advanced system integration in large-scale commercial applications. Furthermore, the windcatcher systems are comprised of three fundamental aspects: form and temporal function, spatial function, and material function (Fig. 12). These aspects convey the basic principles of windcatcher design technique and application. 20

Figure 12. Windcatcher system aspects

2.2.1.1. Form and Temporal Functions The traditional windcatchers are basically classified into five groups based on the number of their sides (faces) [4]. Each category has different temporal behavior based on the airflow streams and form of the windcatcher and the building underneath. Uni-directional windcatchers (Fig. 13A) capture the wind from a single opening at the top of the roof structure and direct it into the building. The air exits from an interior space opening to provide natural ventilation [22]. This type of windcatcher is incorporated on small residential buildings in the regions that have a dominant prevailing wind direction [26]. Bi-directional windcatchers (Fig. 13B) have two openings on opposite sides at the top of the structure. One opening faces toward the prevailing wind direction and operates as an inlet, while the other opening is exhausts the warm air out [27]. The next category is four-sided windcatchers (Fig. 13C), which are a type of multi-directional windcatcher used in regions that have multiple prevailing wind directions or erratic urban wind patterns. All four sides are generally used for catching wind as the air stream direction shifts [28]. The next windcatcher type, primarily used for large scale buildings, has six and eight sides with hexagonal and octagonal cross-sections (Fig. 13D and 13E). These windcatchers are often built in combination with water resources, such as water ponds or water cisterns, to provide evaporative cooling effects in area with hot and dry conditions [29]. The latest geometric evolution of traditional windcatchers is cylindrical (Fig. 13F), though only a few examples of this model are found, and tend to occur mostly in Dubai near hot and humid climate conditions [30].

21

Figure 13. Different types of traditional windcatchers: (A) one-sided windcatchers in Yazd, Iran [31]; (B) two-sided windcatchers in Yazd, Iran [4]; (C) four-sided windcatchers in Kerman, Iran [31]; (D) six-sided windcatchers in Yazd, Iran [32]; (E) eight-sided windcatcher in Dowlat-Abad Garden, Yazd, Iran [31]; (F) cylindrical windcatcher in Dubai [32] Different airflow velocities provide a pressure differential, which causes air to move from higher (positive) pressure zones towards lower (negative) pressure zones. This type of pressure differential is based on the Bernoulli principle, which states when the velocity of a fluid increases the pressure decreases. During the daytime, the movement of wind at the top of building provides a positive pressure on the windward side of the windcatcher and a negative pressure at the leeward side. In windcatchers, the airstream above the roof of the building is captured through the inlet and directs ventilation to the inside of building spaces. At the same time, indoor air can be exhausted from outlets such as windows, doors, or to encourage the natural ventilation cooling pattern (Fig. 14) [4]. 22

Figure 14. A cross section of a space demonstrating the function of a one-sided windcatcher due to pressure differential at daytime The tendency of a liquid or gas to cause less dense objects to float or rise to the top surface of the fluid is called buoyancy. Buoyancy effect happens in part based on the temperature difference with cold air stratifying at the base and hot air rising to the top of a given volume [33]. During night time in desert climates, the mechanism of windcatcher is like a chimney due to the thermal forces and temperature gradient differentials between indoor and outdoor spaces [34]. When the outside air is cooler than the inside, high density cool air descends through the windward side of the device, and at the same time, low density hot air from the indoor space is stacked up through the windcatcher at the leeward side of the device [28] (Fig.15).

Figure 15. A cross section of a space demonstrating the function of a two-sided windcatcher due to buoyancy effect 23

2.2.1.2. Spatial Functions windcatchers have a functional role in cooling and ventilation of various spaces such as living spaces and also the basement of residential buildings, prayer halls of , the pavilions of gardens and the living quarters of (an inn with a central for travelers in the desert regions of Asia or North Africa) [35] [4]. Many windcatchers were applied to balance the humidity inside building spaces and thus they were built above a lavabo (Howzkhaneh), which is a type of subterranean water pool. They were also built on top of water cisterns (Ab-anbar) as a natural system to provide and cold water during the summer [17]. Figure 16 shows integration of windcatcher with different spaces.

Figure 16. Integration of windcatchers with water canals as a medium of evaporative technique [36]

Evaporative cooling is one of the cooling strategies that is combined with windcatchers in several methods. For instance, one of the traditional common modes of integration is with an underground water canal known as Qanat [37]. Also, the combination of windcatchers with water ponds or canals allows the inlet airflow to pass along the surface and induce water vapor to provide evaporative cooling (Fig. 17) [4].

Figure 17. Cooling performance of windcatcher incorporated with underground water channel (Qanat) [38] 24

2.2.1.3. Material Functions Selecting the effective material condition to increase the application of windcatcher as a passive cooling strategy depends on the climate. The used materials for constructing the windcatchers depends on the climate. In hot dry climates, windcatchers are built of mud or baked covered with mud plaster. Mud brick () has high heat resistance because it is made of the uncompressed soil and water, which causes cavities in the brick upon evaporation. These small holes prevent heat transmission through the bricks. Mud plaster (kah_gel) is made of wet soil and straw plant. Because of the hollow spaces within the straws, moisture is retained for a long time and causes evaporative cooling effects as well as increasing the heat capacity of the structure. Also, the light color of mud plaster that covers the facades of windcatchers helps to reflect radiation and thus maintain a cooler temperature inside the structure [35]. Figure 18 shows a sample of these systems that is reinforced with wood framing to achieve the heights that were needed [17].

Figure 18. A windcatcher in Yazd, Iran made of mud bricks with mud plaster cover and reinforced by wood, image by Alireza Javaheri [39] 25

2.2.1.4. Integrated System Advancements As a result of the advantages and beneficial functions of windcatchers, many integrated system innovations of windcatchers were advanced. Contemporary designers took the benefits and principles of the traditional windcatchers and have designed the modern windcatchers with different functional adaptations [40] [4]. windcatchers are now utilized in many commercial applications. The windcatcher building technology is now commonly used to cool down the spaces with high occupant numbers such as schools and office buildings [41]. From 2002 to 2017 more than 7,000 windcatchers were installed in public buildings throughout the UK, exemplifying the prolific application of windcatchers in large-scale commercial buildings [35]. Contemporary windcatchers also incorporate technologies that address both natural ventilation and natural daylighting [28]. These integrations introduce some new technologies that has higher productivity than traditional windcatchers and lower energy consumption than other ventilation systems. For instance, one kind of commercial windcatcher named Monodraught (Fig. 19) demonstrates the integration of a solar panel, a solar powered fan, and adjustable dampers [REF].

Figure 19. Schematic of Monodraught, a windcatcher that integrates a solar powered fan [28]

This new type of windcatcher as applied at the University of Qatar in Doha (Fig. 20) has dampers, various types of sensors, and an adjustable ceiling ventilator that all assist automatic adjustments of the temperature, humidity, air flow, noise level, and CO2 based on the indoor space needs [42]. 26

Figure 20. Advanced system integrated windcatchers at University of Qatar Doha [22]

The other development of the traditional windcatchers is the integration with active heating and cooling systems. This integration is identified as hybrid windcatcher systems, which incorporate computer-based electrical control systems known as energy management and systems (EBAS) and integrated building management systems (IBMS). Both EBAS and IBMS enable the monitoring and control of different cooling, heating, ventilation functions and other energy-saving devices. A building with a hybrid windcatcher system is the Bluewater shopping mall in the UK (Fig. 21). The IBMS is connected to a weather station to determine proper adjustments with the integrated windcatcher devices. The weather station provides real-time information about rain, wind speed and direction, temperature, relative humidity, and snow or wet fog [43] [22].

Figure 21. Internal and external views of hybrid windcatchers in Bluewater shopping mall [22]

27

Because of the dynamic external forces from the environment, passive cooling strategies face significant challenges for maintaining interior building temperatures at the proper and consistent level. For solving this problem, research by Dorit Aviv suggests combining the passive cooling strategy with mechanical actuators to provide an adaptive design that responds in real-time to dynamic environmental variables [5]. The prior research identifies the adaptive roof aperture as an innovative operable roof structure (Fig. 22), which shifts its geometry and adjusts the aperture fins to allow for either downdraft airflow (narrow top neck) or nighttime radiation (wide open top). During the daytime the downdraft form of this structure directs airflow into the building and makes the space cool [44]. At night when outside is cold, the geometry of the aperture changes to wide opening, which exposes the warm interior spaces to the sky. Due to nighttime sky radiation, this opening evacuates hot air to the outside and cools the interior space below. The research also indicates that the system efficiency is affected by its geometry and the material properties of the roof and floor.

Figure 22. Adaptive roof aperture prototype at Princeton University, Copyright by © Dorit Aviv and Forrest Meggers [41] The research also demonstrates that when water mist sprays from the top of the roof aperture it facilitates the outdoor airstream to be pulled down into the indoor space by making the hot dry air both cooler and denser [44]. This example provides a foundation for considering the potentials for downdraft evaporative cooling, radiant sky cooling, and adaptive active controls to work together towards optimization of a roof integrated cooling aperture system. 28

2.2.2. Hydrogel Membranes

Hydrogels are “(t)hree-dimensional molecular structures that absorb water and undergo large volumetric expansion” that have unique potential to be used in buildings [45]. Hydrogels are polymer networks with both physical and chemical cross-links (Fig. 23a). They do not dissolve but rather are hydrophilic and hold water. Hydrogels are readily present in nature through polymers like collagen or gelatin, but also can also be chemically synthesized. Hydrogels are sensitive to environmental changes and thus can be utilized in diverse applications [46].

Figure 23. Hydrogel images: a) SEM at 1µm (left) [47]; and b) saturated gel at 10 cm (right)

Existing research by Aletheia Ida at the University of Arizona demonstrates that superporous polyelectrolyte hydrogels can be integrated into building enclosure systems for effective environmental adaption (Fig. 24). The hydrogel provides multivalent environmental benefits due to its ability to behave in various ways under different environmental conditions and different phases including water sorption, vapor diffusion, thermal capacitance, and daylighting control [6].

Figure 24. Climate responsive adaptive biopolymeric membrane environmental performance criteria for multivalent temporal design conditions [48]

The hydrogel membrane research provides early prototype studies inserted into an environmental test chamber for sensing and evaluating environmental variables and dynamic response. The work also covers alternative fabrication and post-processing techniques for hydrogels to demonstrate the potential of water recuperation membranes [7] [8]. 29

Another example of hydrogel applications in building material systems is the hydrogel-lined block by the Institute for Advanced Architecture of Catalonia (IAAC) group in Spain (Fig. 25). These hydroceramics provide evaporative-cooling through modular apertures that decrease indoor temperature by five to six degrees [49]. In combination, these prior studies and examples of hydrogel integration in building facades for multifunctional environmental response demonstrate some potentials for utilizing the hydrogel in the roof aperture system.

Figure 25. Hydroceramic prototype [49]

30

3. DESIGN HYPOTHESIS

3.1. Multifunctional Adaptive Roof Aperture

Based on the prior work for system and material functionality for adaptive cooling methods in hot- arid climates, the efforts are combined to investigate a hybrid adaptive cooling roof aperture system. A concept for integrating a hydrogel membrane as the inner-lining of the roof aperture surface is proposed (Fig. 26). This integration addresses four primary functions including evaporative downdraft cooling, radiant cooling, natural daylighting, and water conservation [8]. As shown on the left (Fig. 26A) the system utilizes passive diffusion from a hydrogel membrane to induce downdraft evaporative cooling in addition to modulating natural daylighting control. As shown on the right (Fig. 26B), the system functions as a nighttime cooling , the water tanks shown at the floor of the interior space serve to feed water to the membrane in a controlled way, and also allow for water recuperation as condensate drops to the floor of the space.

Figure 26. Schematic diagram of multi-functional system: A) daytime (left); and B) nighttime (right) [8]

3.1.1. Evaporative downdraft Cooling In hot days of spring and summer the aperture acts as a downdraft chimney. When the hot-dry airflow streams interface with a wetted hydrogel membrane, it enables evaporative cooling that helps daytime downdraft. The moisture that is diffused from the hydrogel membrane causes the air to get heavier and rapidly cool down and fall down into the building’s interior space. Furthermore, hydrogels that is a high heat capacitance material encapsulated into the chimney’s enclosure provides radiant cooling during the night and heat that is stored at the material pull out with night stack ventilation. The lyophilized hydrogel that offers humidity sorption, helps night radiation cooling process with dehumidification of air at top of the chimney. 31

3.1.2. Radiant Cooling For increase the effectiveness of radiant cooling other material with high heat capacitance like phase change materials can be applied within the system. Use of phase changed material (PCM) as a of is growing increasingly over the last decades. When the temperature increases more than a melting point of the PCM, the chemical bonds of the material will separate, and material continues to absorb the heat to shift from the solid phase to liquid phase. PCM provide the opportunity of storing solar heat as in a defined temperature range and cooling the space in daytime and then re-radiate the stored heat at the nighttime. Moreover, PCM has the ability of shifting to translucent material for providing natural lighting [50].

3.1.3. Natural Daylighting The integration also addresses Natural daylighting through the hydrogel membrane. The existing studies on hydrogel membrane demonstrates the daylighting and heat transfer based on different saturation rates [6]. When the hydrogel membrane is saturated with water there is higher daylight transmission compared to the dry condition that condenses the polymer chains into a semi-opaque state. In both states, the hydrogel provides some amount of diffuse natural daylighting.

3.1.4. Water Conservation As the last function, the research also explores the potential for rainwater harvesting, which is a crucial issue at hot arid climate due to drought possibility.

The water cycle starts by pumping water into the system. Water is distributed to the hydrogel membrane by spraying into it. At the next step, water is changed to vapor by diffusion from hydrogel and causes evaporative cooling. Then the moisture comes to the interior space with the airflow and ultimately, the vapor is recuperated as water by using lyophilized hydrogel that has the ability of moisture sorption, as the air is pulling out. The water will be released under pressure and could be directed to the water tanks. The heavy monsoon in Tucson, AZ, and winter rains provide opportunities for water harvesting. The rainwater can be collected with the geometry of the windcatcher and be transferred to the water tanks. Moreover, the hydrogel membrane can be applied wherever the rainwater is collected as to saturate the rainwater rapidly and helping to slow the rate of water runoff (Fig. 27). 32

Figure 27. Schematic diagram shows the water recuperation cycle’s four steps[8]

As a complex system and collective design concept being developed by a larger research team, the work of this thesis contributes to analytical aspects for proof-of-concept data on airflow analysis, radiation analysis, and daylighting analysis. While the water conservation benefits and concept are identified, this thesis does not include developmental analysis or data for the water metrics. 33

4. DESIGN ANALYSIS

4.1. Simulation Studies

For implementation of this integration idea and due to its complexity, several digital simulation analyses were conducted. Since the prior research demonstrates improvements to the airflow effectiveness through a unique geometry [5], the subsequent analyses use the same geometry as a baseline for study. The analytical research methods and findings are presented here in the order of the concept functions: airflow analysis for downdraft evaporative cooling, radiation analysis for radiant cooling and solar shading, and daylighting analysis.

4.1.1. Downdraft Airflow Analysis

Airflow analyses were conducted to identify the spatial factors affecting the airflow behavior through the unique geometry. Computational Fluid Dynamics (CFD) simulations were conducted to analyze airflow morphology through different spatial conditions. CFD simulations were performed with the Rhino-Grasshopper Butterfly plug-in accessing the OpenFOAM analysis platform engine with considering the steady-state incompressible that does not include material condition. The mesh grids are established using block mesh discretization method and the snappyHexMesh as analysis grid. Simulations are established on the finite volumetric method [51]. CFD simulations were carried out to evaluate the performance of different geometry of windcatcher incorporate by different space configurations. To identify the geometry of the windcatcher that influencing the airflow morphology, velocity, and pressure, different variables were determined. The overall shape of the windcatcher has a narrow neck with diameter of 1 meter to provide Bernoulli's effect that help the airflow moves toward the interior space with higher velocity. The inlet aperture has 1.5 m diameter and the roof opening has 4 m diameter. The parametric study addresses different heights of the windcatcher and placement of the neck. Three iterations with heights of 2-meters, 4-meters, and 6-meters (Fig. 28) were determined. Also, three locations of neck placement were determined for each iteration: the midpoint, one-third from the top, and one- third from the base of geometry. 34

Figure 28. Parametric iterations of CFD simulation based on chimney height and neck position

The CFD simulations were conducted with the models located over the center of the roof of a cubic space by dimension of: 10Wx10Lx4H. The inlet was set at the top of the windcatcher by assuming downward airflow with 180° angel and 2m/s speed. the outlet is defined on the middle of one wall of the space with the dimension of 2*0.5 meters. Two evaluation planes are established through the mid-sections of the space for plan and section views of the airflow results (Fig. 29).

Figure 29. CFD simulation model setup demonstrates inlet at top of chimney and the outlet on the wall of space below (left) with two evaluation planes (right) [52] The results of the different iterations show that as the height of the chimney increases, the air velocity into the space below will increase too (Appendix A). 35

Figure 30. CFD results for 4-meter height chimney [52]

Within a research team, the full-scale physical prototype will be constructed in 4-meter height with the optimal neck position at the midpoint of the chimney as it provides adequate air speed for ventilation cooling effects. Simulation’s result for 4 meters’ height chimney (Fig. 30) demonstrates the highest velocity in the space is exactly below the chimney where there is downdraft. Vortices form in other spaces of the room are created based on natural buoyancy patterns. Also, because of the pressure differentials between inside and outside of the space, air speed increases while passing through the outlet.

4.1.2. Solar Radiation Analysis

Solar radiation analyses were conducted to figure out the optimal material placement based on material heat capacitance and conduction with determining radiant surface zone. Solar radiation analyses were performed with the Rhino-Grasshopper Ladybug plug-in [53] to determine optimal material integration to decrease the heat absorption and thermal mass overheating and increase the radiant cooling by exposing them as much as possible to the cold sky. The simulations were running for three times of day, 8am, 12pm and 4 pm for three times of year, spring equinox, summer and winter solstice (Fig. 31). Based on the radiation that the geometry gains, the design were modified gradually to reach to an optimal shape. At hot-arid climates, and specifically Tucson, as the sun's rays strike earth's surface the incoming solar radiation is nearly perpendicular or closer to a 90˚ angle. Therefore, the solar radiation is concentrated over the horizontal surface area, so the vertical areas achieve less radiation. Based on this fact and providing a self-shading geometry the iterations 36 were evolved. The total radiation was decreased considerably from 59368 kwh/m2 to 30527 kwh/m2. The annual total radiation for three iterations of design development are as follows:

Table 2. Annual total radiation for three windcatcher geometries Iteration one: 59368 kwh/m2 Iteration two: 47470 kwh/m2 Iteration three: 30527 kwh/m2

The results demonstrate the radiative heat gain of the windcatcher surface fluctuating between 0 kWh/m2 for the shaded and vertical areas to 9 kWh/m2 at the horizontal areas that are completely unshaded per day.

Figure 31. Solar radiation simulation results for iteration one (top), two (middle), and three (bottom) 37

4.1.3. Daylighting Simulation

Daylighting simulation was conducted to measure the illuminance rate that transmits into the interior space in the completely saturated and dried state of hydrogel. Daylighting analyses were performed in Rhino by using Grasshopper plug-in and running Honeybee. Analyses were conducted by assuming, the basic space typology as a closed box with dimension of 6 by 6 meters and height of 1 meter and hydrogel as the whole surfaces of windcatcher membrane. Simulations were accomplished for three times of a day, 8 in morning, 12 noon and 4 at afternoon for spring equinox, summer and winter solstice.

Figure 32. Daylighting study space typology of 1-meter height, 6-meter square underneath oculus.

The visible light transmission percentage of wet compared with dry hydrogel was measured by the light meter and the relative value of 48% for fully saturated hydrogel was utilized for the daylighting simulations (Fig. 33).

Figure 33. Physical test of hydrogel light transmission with light meter 38

The result of simulations demonstrates the light, which transmits from the windcatcher into the interior space has intense illuminance at all over the year except the winter morning. Also, the opening at the top of windcatcher cause some glare spot because the studies were conducted with the top of chimney entirely open. (Fig. 34).

Figure 34. Daylighting renders shows light and bright spots from the windcatcher integrated with hydrogel at winter (A), spring (B) and summer (C) [8] Therefore, to preventing glare and use the diffused natural daylight, the material condition of membrane and adding the top structure for control the high contrast should be considered. The simulation results show the provided lighting ranging from 12000 LUX at the noon and afternoon of spring and summer days to 1200 kWh/m2 at the morning of winter days (Fig. 35). 39

Figure 35. Daylighting analysis results

4.2. Waffle Design Proposal

This research was developed within a research team 1 , which incorporates the hydrogel in a membrane for evaporative cooling and into modules for radiant cooling. The proposal addresses different cooling systems: 1) evaporative cooling that happens when hot air is humidified by diffused water from hydrogel membrane at top part of chimney and causes downdraft; and 2) the radiative longwave sky cooling through thermal mass and reflection of shortwave solar radiation through reflecting coatings [52].

1 The research team to date consists of Dorit Aviv, Aletheia Ida, Forrest Meggers, Maryam Moradnejad, Zherui Wang, and Eric Teitelbaum. 40

Figure 36. Diagram of the proposed multi-functional waffle structure chimney [52]

This project addresses innovations in the adaptive functionality for the windcatcher through advanced materials, such as phase-change-materials (PCMs) and hydrogels, which provide unique heat capacitance and emissivity. The chimney is comprised of modules that are inserted within and shaded by a waffle framing structure (Fig. 36). The proposed full-scale prototype is built and tested at Princeton University and will be transported to Tucson, Arizona for in-situ testing of its response to the specific climate.

5. MODULAR DESIGN TECHNIQUE

5.1. Modular Design Proposal

The design approach was developed based on a modular design that each material module has its own unique dimensions and proportions. The modules were applied on the optimal geometry that was derived from analytical research for either holding material and structural purpose. First, the hexagon cells were distributed all over the chimney geometry. For optimizing the modules condition, the hexagon cells were linked to solar radiation analysis to determine the optimal condition of each module to prevent the thermal mass materials to gain high radiation during the day and being as much as possible exposed to the sky during nighttime. The parameters that were defined to get optimized are distribution, depth, and aperture size of each module. 41

Figure 37. Modular design process (top) and result of optimizing each parameter (bottom)

For each parameter a boundary was defined so when the parameters linked to the solar radiation analysis each module achieved different quantities. Therefore, each module receives its optimal condition in relation to others. This technique was executed in Rhino - Grasshopper plugin and can be used for any other form or building system in any climate. First, the distribution and Quantity of Cells were set to responds to the structural needs of the chimney, so they were distributed relatively with low aggregation toward the vertical parts. Also, at bottom parts of the chimney that gain high radiation and we need thermal mass the modules are larger. After distributing modules all over the chimney, they were connected to the radiation result. The depth of each module ranges between 5 cm to 35 cm, the less depth applied to the modules, which gain less radiation so they are filled with less material and will provide more daylighting. The deep modules are located at the area with high radiation gain prevent high heat exchange as thermal mass. Also, the deep modules, as deep modules absorb more heat during the day should be as much as possible exposed to the night sky, so as the radiant surface zone they have wider aperture to enable the re-radiation (Fig. 37).

42

Figure 38. Modular design of adaptive cooling and daylighting aperture

5.1.1. Evaporative Downdraft Cooling Evaporative cooling as one of the system’s cooling strategies enables with the hydrogel membrane at the top part of the geometry. The modules that are not filled with any material and are located at the top row od modules actuates for letting air gets in. The opening size of these modules can accommodate with the wind direction and speed to provide dynamic response to the micro-climate condition (Fig. 39).

Figure 39. Modular aperture with different size of opening 43

The hat modules are filled with hydrogel and a perforated mesh that keep hydrogel in the modules while letting dry air interface with water vapor diffused from membrane enables evaporative cooling and daytime downdraft (Fig. 40).

Figure 40. The cross section of the system shows evaporative function through the modular design

Hydrogels membrane get wetted by water that pumping from the water tank, which is embedded underneath the hat system and attached to wood structure of hat (Fig. 41). The water tank gets filled by harvesting the rainwater through the shape of hat.

Figure 41. The axon view of hat structure 44

5.1.2. Radiant Cooling The radiant cooling, which provides extra cooling at nighttime happens during the night when outside is cooler than inside. The unsaturated hydrogel membrane assists the air to get sucked out. The modules, which have high sky-exposure incorporate with PCM and work as thermal mass. The heat that is absorbed into these modules during the day, re-radiate to the sky and causes extra cooling effect (Fig. 42). These modules are also capable to actuate and change their opening to wider size toward the sky for extra radiation.

Figure 42. The cross section of the system shows radiant cooling function through the modular design

5.1.3. Natural Daylighting As it mentioned before, the system provides natural daylighting based on different optical properties of hydrogel and PCM material in different environmental condition. The natural daylight addresses in the modular design too (Fig. 43) and is enhanced through the modules, which gain less radiation so are not as deep as others and can transfer higher amount of daylight. 45

Figure 43. Render shows natural daylighting through the modular design

5.1.4. Water Collection Water collection cycle starts with rain harvesting through the shape of hat and is stored in the water tank embedded underneath. From there, the water pumps to the hydrogel membrane and hydrogels get saturated. The water changes to vapor when airflow interface with it and at the end the lypholized hydrogel recapture the humidity from the airflow at the occupied space below the chimney and change it to water under pressure. Figure 44 demonstrates the water collection cycle within the modular design.

Figure 44. Water collection cycle

5.2. Physical Modeling Studies

Due to the complex geometry of the system, a proposal for fabricating pieces separately was developed. For fabricating the prototype integration of different digital fabrication methods such as CNC router, 3ds printing and laser cutting were tested. For fabricating the hat, using CNC router for making a mold to vacuum glass or multi-layer plastic was proposed. Different sizes of hydrogel an PCM modules were printed out by 3ds printer for pouring materials in and conducting physical 46

testing. Also, different cuts were conducted on a flexible textile as a proposed mesh design. Figure 45 demonstrates different digital fabrication methods and how they can perform for fabricating the prototype.

Figure 45. Digital fabrication methods for prototype modeling 47

6. CONCLUSION and FUTURE WORK

Figure 46 shows the overall functions of the system at day and night and how four functions of evaporative cooling radiant cooling, natural daylighting and water collections work within the system.

Figure 46. Diagram of the multi-functional thermodynamic system: day (left) and night (right)

After fabrication, several physical tests could provide information about the efficiency of this multi- functional system. The available LUX at interior spaces for daylighting can be measured with light meters under different hydrogel saturation levels. The temperature and humidity differential as well as airflow velocity provides information regarding cooling and ventilation effect. Also the empirical information about water harvesting, water usage, and rate of moisture diffusion from the hydrogel membrane will determine the efficiency of water recuperation cycle. This information will be informative about the design efficacy for both energy and water conservation. Due to the adaptive function that this material modular system addresses, it can be developed to other areas of built environment. This material module could be integrated with future building as an alternate set of building forms as the actual building “block” for construction or building

enclosure (Fig. 47). Beyond the building design typology that is influenced by environmental conditions of the region and thermodynamic flows, each module could accommodate with forces and interior space needs and situation to provide a localized adaptive function (Fig. 48). In such designs, selection of modules can have diverse functions like natural ventilation, evaporative cooling, thermal mass or natural daylighting (Fig. 49). 48

Figure 47. Different space typologies with unitized adaptive building modules

Figure 48. Modular system adaptive functions based on interior building demands

Figure 49. Modules’ adaptive functions in response to micro-climate forces: a) evaporative and radiant cooling (left); and b) natural ventilation and natural daylighting (right) 49

APPENDIX

CFD simulation: Parametric Modules:

Module A. from left to right. module A1, module A2, module A3

Module B. from left to right. module B1, module B2, module B3

Module C. from right to left. module C1, module C2, module C3

50

CFD simulation results: A1:

51

A2

52

A3

53

B1

54

B2

55

B3

56

C1

C2 57

C3 58

59

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