Heat transfer within linear Fresnel unit using parabolic reflector

Purpose This paper scrutinizes exergy loss and hydrothermal analysis of Linear Fresnel Reflector (LFR) unit by means of FLUENT. Several mirrors were used to guide the solar radiation inside the receiver, which has parabolic shape. Radiation model was used to simulate radiation mode. Design/methodology/approach Heat losses from receiver should be minimized to reach the optimized design. Outputs were summarized as contours of incident radiation, isotherm and streamline. Outputs were classified in terms of contours and plots to depict the influence of temperature of hot wall, wind velocity and configurations on performance of Linear Fresnel Reflector (LFR) based on thermal and exergy treatment. Four arrangements for LFR units are considered and all of them have same height. Findings Greatest Nu and E-x can be obtained for case D due to the highest heat loss from hot wall. Share of radiative heat flux relative to total heat flux is about 94% for case D. In case D when T-r = 0.388, As h(ext) rises from 5 to 20, Nu(total) enhances about 11.42% when T-r = 0.388. By selecting case D instead of case A, E-x rises about 16.14% for lowest T-r. Nu(total) and E-x of case D augment by 3.65 and 6.23 times with rise of T-r when h(ext) = 5. To evaluate the thermal performance (eta(th)) of system, absorber pipe was inserted below the parabolic reflector and 12 mirrors were used above the ground. The outputs revealed that eta(th) decreases about 14.31% and 2.54% with augment of T-in and Q if other factors are minimum. Originality value This paper scrutinizes exergy loss and hydrothermal analysis of LFR unit by means of finite volume method. Several mirror used to guide the solar radiation inside the receiver, which has parabolic shape. DO model was used to simulate radiation mode. Heat losses from receiver should be minimized to reach the optimized design. Outputs were summarized as contours of incident radiation, isotherm and streamline.