Spatial layouts and absorbing surface design of heater tube arrays of direct-illumination receiver used in high power dish/stirling system

摘要

The spatial layout and absorbing surface of heater tubes of receiver has a significant impact on its optical performance. In this paper, the generating method for centerline of heat tubes based on the circular involute projection on three space surfaces such as conical frustrum, hyperboloid of one sheet and paraboloid of revolution (which is defined as type I, type II and type III, respectively) is presented. Meanwhile, the detailed optical simulation is carried out based on three types tube geometries and cavities for direct illumination receiver(DIR). The simulation results demonstrate flux patterns of three types receivers: (1) power absorbed by heater tubes reach 65892.982W, 66757.06W and 65541.864W for type I, II and III receiver respectively at surface absorptivity of 0.9; (2) peak flux for each receiver is 60.351(W/cm2),71.982(W/cm2),58.094 (W/cm2) respectively; (3) the flux gradient of heater tube in circumferential direction is bigger than the one in axis direction; (4) in general, type III and type 1 has a more even flux distribution than type II but type II absorbs more power than type I and type III. Furthermore, type 11 has a great potential in real application if proper gap between tubes and well-matched center plug are adopted. (C) 2019 Elsevier Ltd. All rights reserved.