농업시설 활용을 위한 수치해석 기반 무창기공형 태양열 집열기 열성능 평가

Abstract

In this study, an experimental setup for an unglazed transpired collector was developed to evaluate temperature variations and efficiency. Temperature variations and efficiency were measured using the experimental setup and predicted through a numerical analysis based on computational fluid dynamics (CFD) and a 3D model. Finally, the measured and predicted values were compared and analyzed to evaluate the potential applicability for agricultural buildings. The experimental setup and scaled-down 3D model without repetitive shapes were developed to conduct the experiments and simulations. Under the same experimental conditions, the maximum measured outlet temperature was 65.4°C, whereas the predicted temperature was 65.2°C. The coefficient of determination (R²) and root mean square error (RMSE) obtained from the comparison between measured and predicted values for the unglazed transpired collector were R²=0.64, RMSE=5.76°C for the absorber surface temperature; R²=0.98, RMSE=2.65°C for the plenum temperature; and R²=0.99, RMSE=0.83°C for the outlet temperature. The average experimental thermal efficiency of the unglazed transpired collector was 66%, whereas the numerically predicted efficiency was estimated to be 72%.