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Analysis of Thermodynamic Parameters and Their Influence on the Thermal Comfort in the Working Environment

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Analysis of Thermodynamic Parameters and Their Influence on the Thermal Comfort in the Working Environment MATEC Web of Conferences 168, 04002 (2018) https://doi.org/10.1051/matecconf/201816804002 XXI. AEaNMiFMaE-2018 Analysis of thermodynamic parameters and their influence on the thermal comfort in the working environment Zuzana Kolková1,*, Peter Hrabovský1, Jozef Matušov1, and Radovan Nosek2 1University of Žilina, Research centre, Univerzitná 8215/1, 010 26 Žilina, Slovakia 2University of Žilina, Department of Power Energy, Univerzitná 8215/1, 010 26 Žilina, Slovakia Abstract. Air quality inside the building is an important measure of comfort for people living and working in it. Achieving optimal air quality requires a regulated indoor air control system, often in combination with thermal regeneration. Typical short ventilation, irregular window and door ventilation are rarely adequate. From the point of view of the thermal comfort of the environment, it is necessary to predict the development and selection of suitable systems for the thermal comfort of the environment to predict how many thermal factors will affect the population, room temperature uniformity, asymmetry of the radiation temperature, and turbulence intensity of the flowing air. People are capable of detecting heat, temperature changes can feel not only globally, but also as local heat loss on the parts of the body. Thermal comfort is given by the air temperature and radiant heat, air velocity and relative humidity in the room. The main impact of these factors on the comfort level of individuals depends on the activity and type of clothing. The bad thermal comfort is detrimental to workers' health, increasing the risk of accidents and affects adverse effects on the psyche. The assessment of impact of the working environment to human form comparing actual and optimal parameter values of the working environment. 1 Introduction The human body is a continuous source of heat. This metabolic heat production is divided into basal and muscle metabolism. Basic metabolism is the heat produced by biological processes. Muscle metabolism arises in human activity. Heat produced by the organism must be taken to the environment or body temperature changes. The temperature inside the human body is around 37 °C, while the skin temperature may range from 31 to 34 °C depending on the surrounding environment. Differences arise over time but also by parts of the human body [1]. Indoor environments in buildings create many components. Thermal humidity, smell, aerosol, microbial and acoustic components are essential. The basic influence on people has the thermal humidity parameters of the living room. In terms of impact on human health, air * Corresponding author: [email protected] © The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/). MATEC Web of Conferences 168, 04002 (2018) https://doi.org/10.1051/matecconf/201816804002 XXI. AEaNMiFMaE-2018 quality seems to e the most important fator. ost of these environmental omponents are affete y ventilation 2]. pae temperature uniformity, asymmetry of the raiation temperature, and turbulene intensity of the flow air affet thermal omfort People are apale of eteting heat and they an feel hanges in temperature globally on the entire surfae of the body ut also loally on ody parts. t has een shown that humans an alimate to ambient temperature physiologially and psychologially. It is therefore important to adress the issues of thermal omfort in the interiors builings) and to eperimentally etermine a suitale way of reating the optimal onditions of the environment The goal is to ensure a sense of satisfation from the environment and also to inrease work performance an a sense of comfort 3]. 2 Dantec system Comfortense is a multihannel system for measurement air eloity and air temperature, humiity and operatie temperature t alulates statistial values – raught rate (DR), Preite ean ote (PMV) and Preite Perentage issatisfie PPD). Comfortense an e use for many appliations inluding C researh and eelopment, testing of ventilation euipment, builing researh, passenger omfort studies in the automotie and aiation industries hermal omfort measurements with Comfortense omply with International Stanars N 131, ISO 772, 3, SHRAE stanar 113 an SHRAE standard 5. he Comfortense system onsists of a main frame with input hannels for up to 16 probes The omniiretional probes measure both air eloity and temperature The ruggely esigne probes and ables are perfetly suited for large test rooms. he draft probe is euippe with an omniiretional thin-film sensor for measuring air veloity and a small fast-response thermistor for measuring air temperature igure 1) Fig. 1. The raft probe, robust velocty tmperatur robe and ankin verson. The manikin ersion of the draft probe is ery ompat, with a fleile able onnetion to the probe tip, making it suitale for uiling into a manikin for passenger omfort appliations. eloity range is .05 to m/s, indiates up to 10 m/s and temperature is - to 0 °C for both types. Robust velocity and temperature probe has veloity range 0.1 to 3ms. Humiity range is – 1 ante has also operatie temperature probe The sensor element simulates a standing person when it is ertial, a sitting person when tilte 30 °C from vertical and a reclining person when in the horizontal position. Temperature range is – 4 °C (Figure 4]. Fig. 2. Humidty robe, operatve tpratur rob ad an rame. 2 MATEC Web of Conferences 168, 04002 (2018) https://doi.org/10.1051/matecconf/201816804002 XXI. AEaNMiFMaE-2018 quality seems to e the most important fator. ost of these environmental omponents are 3 ASHRAE STANDARD 55 affete y ventilation 2]. pae temperature uniformity, asymmetry of the raiation temperature, and turbulene RAE tandard 5 (Thermal Environmental Conditions for uman ccupancy) is a intensity of the flow air affet thermal omfort People are apale of eteting heat and standard that provides minimum reuirements for acceptable thermal indoor environments. they an feel hanges in temperature globally on the entire surfae of the body ut also It establishes the ranges of indoor environmental conditions that are acceptable to achieve loally on ody parts. t has een shown that humans an alimate to ambient temperature thermal comfort for occupants. Percent dissatisfied (PD) represent percentage of people physiologially and psychologially. It is therefore important to adress the issues of predicted to be dissatisfied due to local discomfort. Predicted mean vote (PMV) is an index thermal omfort in the interiors builings) and to eperimentally etermine a suitale way that predicts the mean value of the votes of a large group of persons on the seven point of reating the optimal onditions of the environment The goal is to ensure a sense of thermal sensation scale. redicted percentage of dissatisfied (PPD) is an inde that satisfation from the environment and also to inrease work performance an a sense of establishes a uantitative prediction of the percentage of thermally dissatisfied people comfort 3]. determined from MV 5-7. 2 Dantec system 4 Experimental setup Comfortense is a multihannel system for measurement air eloity and air temperature, We have a laboratory of chemical analysis. his workplace has three devices, which have humiity and operatie temperature t alulates statistial values – raught rate (DR), furnaces with heating up to 500 °C. We have several systems to ensure optimal working Preite ean ote (PMV) and Preite Perentage issatisfie PPD). Comfortense conditions. he laboratory is oriented to the outh-East side. Roller shutters are installed on an e use for many appliations inluding C researh and eelopment, testing of the windows to regulate the intensity of sunlight during the day when the laboratory is most ventilation euipment, builing researh, passenger omfort studies in the automotie and used. Floor heating is used to provide heat ceiling cooling to ensure the cold. aiation industries hermal omfort measurements with Comfortense omply with The ventilation of the laboratory is ensured by circulating air through the ceiling spouts. e International Stanars N 131, ISO 772, 3, SHRAE stanar 113 an SHRAE also use a ceiling air-conditioning unit to reduce room temperature. f all three devices are standard 5. he Comfortense system onsists of a main frame with input hannels for up in full operation, room temperature rises rapidly. orkers are subject to varying to 16 probes The omniiretional probes measure both air eloity and temperature temperature changes in a relatively short time in this laboratory. Laboratory space is m The ruggely esigne probes and ables are perfetly suited for large test rooms. he draft high (Y), wide is .5 m (X) and long m (Z). he basis of eperimental verification of probe is euippe with an omniiretional thin-film sensor for measuring air veloity and a laboratory environment parameters will be the monitoring and graphical comparison of small fast-response thermistor for measuring air temperature igure 1) PMV, D, velocity, humidity and operating temperature. he standard 3 540- determines the optimal values of environmental parameter according to the purpose of use. etting the room measurement and parameters is in the antec program. t is possible to set the room size location of the measuring probes in the space, display options. The natural state of the environment the working status of the various analysers, the use of the air- conditioning unit the draft and various weather conditions can be simulated using the laboratorys technological euipment. Fig. 1. The raft probe, robust velocty tmperatur robe and ankin verson. 5 Results of measurement The manikin ersion of the draft probe is ery ompat, with a fleile able onnetion to the probe tip, making it suitale for uiling into a manikin for passenger omfort easurement of environmental parameters was performed during simulated loads. he first appliations. eloity range is .05 to m/s, indiates up to 10 m/s and temperature is - measurement was in full operation (PP), load conditions were monitored at full operation of to 0 °C for both types.
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