OPTIMIZATION OF REFRIGERATION MACHINERY

Abstract

A simple vapour compression system is assumed to be made up of a compressor, a condenssor, an expansion valve, an evaporator, and an electric motor. The efficiency of the evaporator, condenser, compressor and electric motor are chosen as the decision variables which are to be optimised so that total annual cost compr-istng the running cost Celectricity consumptiori..)and cost for investment of each equipment is obtained. For getting the system elobaty optimum the optimisation procedure Montecarto and Gradient Method is used and a proeranw),-- is developed .accordingly. The opt tmaL ty given by programme is varified by varying the each decision variable at one time around the Local optimum. parameters such as price of the electricity, the temperature of delivered refrigeration effect etc. may vary among optimisation. To see the effect of the temperature of delivered cooling effect three fottowing cases are studied for five refrigerants, R-12.R-22, R-114, R-502, and .R-717. 1. Milk ChitLing Plant 2. Ice making Plant 3. Aircodi t ioniTte Plant The rsuLts shoves that annual cost is maximum for R-114 and minimum for R-717 in each case. At tower t®nipEarctturo of t o do word cool ir►r' of foc t , ! . __ ( X71 annual cost per tonne of refrigeration effect is higher. Also its relativeV difference• for refrigerant is higher at Lower evaporator temperature and this di f feranc i5 maximum for R.-if 4 among the five refrigerants taken for the study. At lower temperature.exergy Losses and alectrictty consumption rate are also higher. so, at Lower temperature of cooling effect deLverd the selection of refrigerant is rnor important than at higher temperature of cooling effect de L i verd for getting Lesser minimumn. total annual cost.. iV