A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development

Thesis (M.Sc.) - Asian Institute of Technology, 1982

A variable speed compression refrigeration test set-up was designed and fabricated to investigate the feasibility of its direct coupling with compatible windmills. The system was experimented with in order to evaluate the effect of "cold production" with various power input patterns and to pinpoint those parameters that severely affect its desired cooling performance due to the instantaneous fluctuations and intermittent availability of power. Suggestions have been made at a later section for possible solutions to the problems encountered in direct coupling. In the indoor test set-up a variable speed thyristor controlled eddy current motor was used to simulate a few ideal windmill output patterns. An input/output port with analog-digital and digital-analog converters was tested and developed to interface with a Z-80 microcomputer. The microprocessor was programmed to: i. control the variable speed motor; ii. track the variations of different parameters critically with respect to time; iii. process the acquired data from various transducers. Finally an analytical procedure has Been described to assess the viability and applicability· of such a system for a specified refrigeration requirement at a site of known wind regime, It has been experimentally proved that such a system is feasible with a slight modification in its designing to withstand large fluctuations in the windspeed, and to preserve the additional cooling effect during strong winds for later usage during low-winds or no wind periods. As the condenser and the compressor irreversibilities increase with increasing compressor speed, suggestions have been incorporated to improve the heat transfer area and orientation to take advantage of the strong winds and increase the heat transfer rate.