System optimization of an absorption refrigeration system

• Main Author: Chan, Ryan Yaowei
• Other Authors: Cai Wenjian
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: http://hdl.handle.net/10356/60822
• Institution: Nanyang Technological University

Most conventional air-conditional unit used in homes and offices are high power consumption. Hence, contributing to the high cost in electricity bills. The refrigerator cools the area in it effectively with reasonable power consumption. In this project on Absorption Refrigeration System, we use the Laws of Thermodynamics with the implement of absorption chiller into our system that not only cools the temperature in the room efficiently but also uses lower energy consumption and recycles waste heat back to the system. The reason behind this concept is the theory on Laws of Thermodynamics. In conventional compression refrigeration, it only uses refrigerant like R134a as coolant with compressor to cool the room. To design a system that has the cooling efficiency of the fridge and the ability to cool a much larger area with low energy consumption, additional components like the bubble absorber, electronic evaporation valve and ionic liquid absorbent have to be implemented. By using the Law of Thermodynamics, first law states that conservation of energy is the net change of the energy of a system is equal to the net transfer of energy across the system boundary as heat and work. Second law states that the entropy of an isolated system never decreases, because isolated system spontaneously evolves towards thermodynamics equilibrium. This means that liquid will have a lower boiling point in a high pressure system and that the entropy will not decrease throughout an isolated system. With refrigerant in the gaseous state at a lower boiling point means that heat transfer can be much more efficient and ionic absorbent are necessary to convert the vapor refrigerant in the back to liquid state which in turn helps the refrigerant to circulate throughout the system. Research and analysis needs to find the optimum ratio of refrigerant and absorbent as well as the optimum parameters to yield ideal results and performance. The goal is to use low-grade energy such as industrial waste heat and solar energy to run the system with the cooling efficiency to cools the room like a conventional cooling unit but with much lower power consumption as compared to conventional cooling unit.