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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 Ex 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 Tr = 0.388, As hext rises from 5 to 20, Nutotal enhances about 11.42% when Tr = 0.388. By selecting case D instead of case A, Ex rises about 16.14% for lowest Tr. Nutotal and Ex of case D augment by 3.65 and 6.23 times with rise of Tr when hext = 5. To evaluate the thermal performance (ηth) of system, absorber pipe was inserted below the parabolic reflector and 12 mirrors were used above the ground. The outputs revealed that ηth decreases about 14.31% and 2.54% with augment of Tin 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.

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In current article, influence of radiation and convection modes on behavior of air inside an absorber in trapezoidal shape has been investigated. Such cavity is part of Linear Fresnel Reflector (LFR) unit and it is important to analyze such geometry to reach higher performance. Properties of carrier fluid were assumed as function of temperature. To involve radiation effect, discrete ordinates model was implemented. Influences of external convective factor (hext), Angle of adiabatic wall (θ), temperature ratio (Tr) on irreversibility and heat transfer were depicted in outputs. Augment of Tr, θ and hext cause incident radiation to decline about 85.95%, 20.97% and 20.68% with assuming lowest values of other factors. Strength of eddy, temperature difference augments about 180% and 9.77% when θ enhances at Tr = 0.8. With considering highest level of other factors, as values of wind speed and θ intensify, Nu enhances 9.28% and 17.36% while it declines about 52.2% with rise of Tr. Given minimum values of other parameters, irreversibility intensifies about 45.45% and 8.3% with augment of hext and θ but it declines about 84.44% with augment of Tr.