Experimental Investigation Of Phase Change Material Integrated Vapor Compression Refrigeration System

Abstract

Usage Of Vapor Compression Refrigeration System Imported From Abroad Has Become Very Common In Household And Small To Large Scale Food And Beverage Serving Businesses In Ethiopia. But, The Frequent And Also Sudden Electric Power Interruption And Cut For About Eight Hours In Ethiopia Is Causing Spoliation Of Food Items & Products Stored In The Refrigerators And Also Shortage Of Cold Drinks In Commercial Places. This Problem Can Be Solved By Integrating (Pcm) With The Condenser And Evaporator Of Any Vapor Compression Refrigerator System. The Major Objectives Of This Thesis Are To Analytically Design And Experimentally Investigate The Performance Of A Locally Constructed Vapor Compression Refrigeration System With And Without Integration Of Three Different Pcm On The Evaporator And Condenser Of The Refrigerator. The Main Components Of Vapor Compression Refrigeration System Were Selected And Analytically Designed. Pcm, Filter Drier, And Cold Thermostat Is Selected Based On The Requirement. Finally, The Refrigerator Parts Are Assembled And Leakage & Pressure Test Were Conducted. The Refrigerator Has A Cooling Capacity Of 0.433 Kw With Compressor Power Input Of 0.186 Kw. Then, Performance Of The Refrigerator Was Analyzed In Terms Of Coefficient Of Performance, Exergetic Efficiency, On-Off Ratio, On-Off Frequency And Measurement Of Temperatures Of Condenser And Evaporator. Experimental Investigation Done By Integrating Paraffin Wax Pcm (In The Thickness Range Of 2 Up To 5 Mm) On The Condensers Shows A Decrease In On-Off Ratio And 11-34% Increase In Cop. From The Thickness-Based Investigation, It Was Observed That Increasing The Pcm Thickness More Than 2 Mm Causes Decrease In The Cop Of The Refrigerator. Integrating Sodium Chloride Pcm On The Evaporator Gives A 2-9% Cop Increase, A Decrease On-Off Ratio, And An Increase On-Off Frequency. From The Experiment 18 ??? Temperature Fluctuation Of The Refrigerated Cabinet Was Observed Over Three Hours Of Running The Refrigerator Without Pcm. But This Fluctuation Was Reduced To 1.6 ??? When Integrating Sodium Chloride Pcm On The Evaporator. The Experimental Test Done By Integrating Pcm Both On The Condenser And Evaporator Give: Less Temperature Fluctuation, A 727% Cop Increase, Increase On-Off Ratio, And Decrease On-Off Frequency. The Effect Of Integration Of Paraffin Wax Pcm On The Condenser Was Also Done On A Standard Household Refrigerator (Cooling Capacity A 1 Kw; Compressor Power 0.25 Kw) On Freezing Water Of 30 Kg Which Results In Increase Of Cop By 26%. Was Obtained.