ABSTRACT

ABSTRACT This project is one in the series of work in solar cooling at the Mechanical Engineering Department of Ahmadu Bello University, Zaria. It is also a major improvement on the previous work done in solar refrigeration. The results and experience are presented. In the system, the solar absorber and the refrigeration system's ammonia generator are combined to form one unit. Design calculations based on the refrigeration load of the cold room which was built earlier were made and consequently, the various other components were constructed. Air cooling of the components by natural convection was adopted because of easier availability of air and to eliminate running costs due to the use of water. The components were built and assembled at the department's workshop.(See PLATES I and II). Leakage tests were performed using compressed air and soap bubbles. The system was charged with ammonia gas and ammonia-water solution. However, the available pump used was not suitable for the suction of the required ammonia-water solution and the system's circulation, as it is not self-priming. Because of this, the vapor generated in the solar collector could not circulate to achieve continuous refrigeration. Intermittent refrigeration was achieved by the use of a vacuum pump. The results obtained are given in this report. Also recommendations for further modification of the plant are presented.