Prediction of the energy consumption of household refrigerators and freezers via steady-state simulation

A simplified model to assess the energy performance of vapor compression ‘on–off’ controlled refrigerators is presented herein. The model consists of first-principles algebraic equations adjusted with experimental information obtained from the refrigeration system under study. The experimental work consisted of controlling and measuring the system and component operating conditions in order to gather key information for the development and validation of the model. The methodology showed similar accuracy to that using more sophisticated dynamic simulation codes, but with lower computational costs. When compared to experimental data, the model predicted AHAM energy consumption tests within a ±5% deviation band. A sensitivity analysis considering the number of tube rows in the condenser coil, the number of fins in the evaporator coil and the compressor stroke is also reported. The refrigeration system under study was a top-mount ‘Combi’ 600-l refrigerator, ‘on–off’ controlled by the temperature of the fresh-food compartment.