The design of an evaporator for the solar energy powered absorption refrigeration system

The purpose of this report was to design one of the major components of a newly developed Solar Energy Powered Absorption Refrigeration System which was intended for use in air conditioning systems for residential and commercial projects. This component is the evaporator section of the system. The basic refrigerative system uses sodium thiocyanate (NaSCN as the absorbent medium, and ammonia (NH3) as the refrigerant. The heat required to drive the ammonia out of solution is supplied by the system solar collectors delivering 215° F water. In the design and testing of the evaporator, detailed investigation and experiments were made not only on necessary steps required for the design of the evaporator, but also on the related components of the apparatus which have certain influence on the heat transfer process and performance of the evaporator. In addition to the fundamental steps involved in the design, such as: cooling load analysis, material selections, evaporator housing and heat transfer element design, air duct and piping system design, etc., efforts were also made on investigating various methods for control of the system refrigerant liquid and vapor flows, pressure regulating, and refrigerant distribution techniques required for proper function and performance of the evaporator in connection with the entire absorption system as a whole.