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Solar Absorption Chiller Craig Carlson Santa Clara University Santa Clara University Scholar Commons Mechanical Engineering Senior Theses Engineering Senior Theses 6-12-2014 Solar absorption chiller Craig Carlson Santa Clara University Mark Coulter Santa Clara University Claire Kunkle Santa Clara University Patrick Watson Santa Clara University Follow this and additional works at: https://scholarcommons.scu.edu/mech_senior Part of the Mechanical Engineering Commons Recommended Citation Carlson, Craig; Coulter, Mark; Kunkle, Claire; and Watson, Patrick, "Solar absorption chiller" (2014). Mechanical Engineering Senior Theses. 35. https://scholarcommons.scu.edu/mech_senior/35 This Thesis is brought to you for free and open access by the Engineering Senior Theses at Scholar Commons. It has been accepted for inclusion in Mechanical Engineering Senior Theses by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Santa Clara University School of Engineering Senior Thesis Solar Absorption Chiller Submitted By: Craig Carlson Mark Coulter Claire Kunkle Patrick Watson University Advisor: Professor Hohyun Lee Submitted on the Date: 12 of June, 2014 Submitted in Partial Fulfillment of the Requirements for the Bachelor of Science Degree in Mechanical Engineering in the School of Engineering Santa Clara University, 2014 Santa Clara, California Abstract In developing nations access to electricity is inconsistent at best, and food spoilage is a prevalent issue. The solar powered absorption chiller is a refrigeration system designed to provide refrigeration to these developing areas. This year, our team has worked to develop a system where the sun’s rays are collected as heat to power an absorption refrigerator. The goal of this project was to take an existing solar tracker system and use its collected heat to power a refrigerator. Our team designed and built heat exchangers to extract heat from the concentrated solar system; assembled components for a fluid circulation loop; and retrofitted an absorption chiller refrigerator to be powered by our heated fluid. Additionally, we redesigned an existing solar tracking system to improve function and decrease power consumption. By the end of this year we assembled the entire system and performed months of solar testing as well as proof-of- concept testing that the refrigerator could receive necessary heat through a heated fluid. By the end of the school year, we concluded that the heated fluid would need to reach 150°C to begin the refrigeration cycle (with current heat exchanger design), which was 25° higher than our solar testing had achieved. With further improvements, the refrigerator could be designed to run with lower heat inputs and the tracker system could be designed to attain heat at higher temperatures. With these changes, a working refrigeration system could have dramatic impacts on farming communities in developing countries; reducing food spoilage, increasing family income, and preventing food-borne illnesses. i Acknowledgements Thank you to the California Energy Commission and the Roelandts Grant Foundation for Funding Thank you to Professor Hohyun Lee and other engineering professors who provided us guidance during all phases of this project. Thank you to Don Maccubin in the Mechanical Engineering Lab who provided advice in all manufacturing and provided us with a space to perform heater testing. Thank you to Jeff Charles at the SCU Facilities for the use of their roof for all Solar Testing activities. Finally, thank you to our friends and family for supporting us through this project. Without all of you this project would not have been possible! ii Table of Contents Chapter 1: Introduction ....................................................................................................................1 1.1 Background ..........................................................................................................................1 1.2 Literature Review.................................................................................................................2 1.3 Project Objectives ................................................................................................................6 Chapter 2: System Overview ...........................................................................................................7 2.1 Concentrated Solar Power (CSP) .........................................................................................7 2.2 Absorption Chiller Technology ...........................................................................................9 2.3 Subsystems Overview .......................................................................................................10 2.4 Customer Needs .................................................................................................................12 2.5 Benchmarking Results .......................................................................................................13 2.6 Functional Analysis ...........................................................................................................15 2.7 Key Systems Level Issues ..................................................................................................16 2.8 Team and Project Management .........................................................................................19 Chapter 3: Subsystem Level Chapter ............................................................................................23 3.1 Absorption Refrigeration Subsystem .................................................................................23 3.2 Solar Tracker Subsystem ...................................................................................................28 3.3 Solar Receiver Subsystem..................................................................................................35 3.4 Fluid Circulation Subsystem ..............................................................................................36 Chapter 4: System Analysis & Testing ..........................................................................................39 4.1 Receiver FEA Analysis ......................................................................................................39 4.2 Fluid Block FEA Analysis .................................................................................................41 4.3 Solar Testing ......................................................................................................................45 4.4 Refrigerator and Heater Testing .........................................................................................47 4.5 Cost Analysis .....................................................................................................................49 4.6 Patent Search ......................................................................................................................50 Chapter 5: Engineering Standards and Constraints .......................................................................51 5.1 Environment .......................................................................................................................51 5.2 Manufacturing ....................................................................................................................51 5.3 Economic ...........................................................................................................................52 5.4 Health and Safety ..............................................................................................................53 5.5 Ethics..................................................................................................................................54 Chapter 6: Summary & Future Work.............................................................................................55 6.1 Summary ............................................................................................................................55 6.2 Future Work .......................................................................................................................55 iii References ......................................................................................................................................57 Appendix 1: Product Design Specifications ..................................................................................59 Appendix 2: Project Budget ..........................................................................................................61 Appendix 3: Project Gantt Chart ...................................................................................................63 Appendix 4: Heat Exchanger Calculations ...................................................................................65 Appendix 5: Fluid Block Temperature Change Calculations .......................................................67 Appendix 6: Detail Drawings ........................................................................................................70 Appendix 7: Assembly Drawings ..................................................................................................80 Appendix 8: Patent Disclosure .......................................................................................................84 Appendix 9: MBTI Results ..........................................................................................................106 Appendix 10: Tracking System Overview ..................................................................................108
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