Vfvv

In: English and Literature

Submitted By vkey95
Words 5785
Pages 24
Journal of Mechanical Engineering and Automation 2015, 5(1): 20-28
DOI: 10.5923/j.jmea.20150501.03

Effect of Evaporator Heater Power Input and Refrigerant
Flow Rate on the Performance of a Refrigerator –
Developing Empirical Models
Ali Naif*, Abdulkareem Shafiq Mahdi Al-Obaidi, Mohammad H. Nassir
School of Engineering, Taylor’s University, Malaysia

Abstract Refrigerators normally are systems that are used to preserve perishable goods in a house hold by reducing the temperature of the food compartments. However, refrigerators are also infamous for their high electricity consumptions.
This paper presents first a comparison between theoretical and experimental determination of the tons of refrigeration (TR) of a vapor compression refrigeration cycle (VCRC). Then, it was looked into the derivation of empirical models, grounded on experimental results, which would provide refrigerator designers a reliable mean to check on the impact of each examined parameter on the TR during the preliminary stage of refrigerator design. It was noted that both evaporator heater power input (EHPI) and refrigerant flow rate (RFR) positively affected the tons of refrigeration, while the effects of condenser water flow rate (CWFR) was negligible. A total of three models generated. As the accuracy of the data for all models were about 99.7%, the minute difference had to be looked in to. Hence, Model 1, considering both evaporator heater power input (EHPI) and refrigerant flow rate (RFR), produced a lower range of error compared to model 2 and 3.
This indicated that Model 1 was the best predictor of TR. The outcomes of the final model were within the uncertainty range of 4.82% and-3.14% compared to the experimental results. This was with in the acceptable range of ±10%. The overall model could be enhance by incorporating other significant evaporator side parameter as…...

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