Factorial experimental design for second law analysis of panel radiators as a function of radiator dimension

Abstract

In this study, the parameters affecting the second law efficiency of panel radiators commonly used in heating systems were investigated. In the experimental system, a total of 6 pc-11 type panel radiators in 2 different heights and 3 different heights were used. In this context, the experiments were carried out by changing the feedwater temperature from 30 °C to 60 °C, with 10 °C increments and the flow rate from 2.5 l/min to 10 l/min, with 2.5 l/min increments. The experimental results obtained were analyzed factorially, and a mathematical model was developed between input parameters (feedwater temperature, flow rate, and radiator dimensions) and output parameters (total heat transfer coefficient and entropy generation). Using the novel model, the heat transfer and irreversibilities that can be obtained from the panel radiator in an operating system with known parameters can be calculated directly. This will provide a design methodology for researchers and engineers to be used for applications in the field. The total heat transfer coefficient and entropy generation from the panel radiator; radiator size increases with increasing flow rate and supply temperature; It has been observed that the total heat transfer coefficient decreases with the radiator size and temperature increase and increases with the increase in flow rate . The results showed an inverse relationship between the feedwater temperature and radiator size and the total heat transfer coefficient. It was also observed that the feedwater temperature was the most significant parameter on the total heat transfer coefficient. The main conclusion is that the most efficient energy utilization is provided by operating the heating systems at low temperatures with high flow rates. Consequently, this will lead to more efficient use of energy and reduced costs and environmental impact. • A factorial experimental study was carried out. • The influence of parameters on model results were analyzed statistically. • A mathematical model was developed. • The parameters exerting the most influence on the total heat transfer coefficient were determined. • The parameters exerting the most influence on entropy generation were determined.