Numerical Investigation on Trapezoidal Cavity Receiver Used In LFR with Water Flow in Absorber Tubes

[摘要] In the present study, numerical three dimensional model of trapezoidal cavity used in LFR was analysed. Results are presented in the form of Thermal losses occurring from the receiver operating with an absorber tube temperature from 350-550 K in step of 50 K and emissivity varied from 0.5-1.0. Effect of wind blowing below lower glass plate (cavity aperture) were also analysed considering the heat transfer coefficient from 5 to 25 W/m2K. At lower absorber temperature (350 K) convective losses is found to be 43% of the total heat loss whereas radiative losses accounted 57%. For higher absorber temperature radiative losses are dominant (77%) and convective losses are reduced to 23%. The air temperature gradient in the horizontal direction (parallel to lower glass plate) is found to be negligible whereas it is varied significantly in vertical direction (normal to lower glass plate). The average cavity air temperature is observed to be 480 K for low wind flow (h=5 W/m2K) and it reduces to 360 K for h=25 W/m2K. This has resulted in increased convective losses (27% higher).

[发布机构] Research Scholar, School of Mechanical Engineering, Lovely Essional University, Punjab, Jalandhar; 144411, India^1;School of Mechanical Engineering, Lovely Essional University, Punjab, Jalandhar; 144411, India^2

[效力级别] 航空航天工程 [学科分类] 航空航天科学

[关键词] Absorber temperatures;Absorber tubes;Air temperature;Convective loss;Numerical investigations;Three-dimensional model;Trapezoidal cavity;Vertical direction