Numerical Optimization of a Household Radiator and Experimental Investigation of Its Thermal Capacity

Authors

Abstract

 

Radiators are common devices for heating of home and office spaces and have a close relationship with the energy sector. In a radiator, heat transfer is increased with increasing of air flow rate along heated surface as well as temperature difference between bulk air and heated surface. First, in order to find the optimum design of an Aluminum radiator numerical analysis of free convection heat transfer using commercial software Fluent was performed and then to thermal evaluation of it the Iranian national standard 4022 which is accordance with international standard ISO 3148 is used as reference experiment. In according to the standard, the test room includes a double room: interior and exterior chamber. The radiator is placed inside the chamber and the exterior chamber is cooled using cooled air. Here, three sets of experimental test are performed at different average of inlet and outlet water temperature of 80 ± 5, 65 ± 5 and 50 ± 5 °C. The average temperature of the interior testing room is controlled by 20 thermocouples mounted in the test room to be maintained in the range of 19 to 21 °C. Experimental results of the radiator heat rate were compared with numerical analysis and good consistency between results was found.

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