Experimental Investigation On Heat Transfer Of Rectangular Enclosure With Quarz Glass-cover Under Wind Condition

In order to investigate the coupled heat dissipation characteristics inside and outside the rectangular enclosure,the wind tunnel and an experimental setup featured by rectangular enclosure with quartz glass-cover were established.Under environmental wind condition,the baseplate of enclosure was heated electrically by heating foil.This experiment aims at investigating the impact of partitioned or non-partitioned condition,heat gradient parameter k,tilt angle?,wind incidence angle?,environmental wind speed V and heat flux q on heat loss.The variation of combined heat transfer coefficient on the external surface of quartz glass-cover with that inside the enclosure,and the variation characteristics of average Nusselt number inside the enclosure and the variation characteristics of average Nusselt number outside the enclosure were investigated and obtained.Main results are shown as follows:Compared with the rectangular enclosure without partitions,local temperature difference in partitioned enclosure is smaller,indicating that partitions inside the enclosure can make the temperature distribution of baseplate more uniform.With the environmental wind speed increasing,the combined heat transfer coefficient inside the enclosure h_in is always lower than that on external surface of quartz glass-cover h_exx which indicates the wind speed has much impact on the heat dissipation on external surface of quartz glass-cover.Besides,partitions also affect h_in and h_ex significantly.When heat flux is in high value,Nu_im both in partitioned and non-partitioned enclosures change in some rules with the augmentation of tilt angle,and the extremums of Nu_imm occur in the condition of the tilt angle is approximately 45°.When heat flux is low,tilt angle has little influence on Nu_em.With the condition of k=0,the effect of?and?show different trend inside and outside the enclosure,and with high wind speed,the influence is more significantly in partitioned enclosure.Except for special cases,Nu_im fluctuates with the increase of V which means V affects the heat dissipation inside enclosure acutely while Nu_em is in nearly direct proportion to V.When?=0°,both Nu_im and Nu_emm are in some rules with the rise of q,while in the condition of?=180°,Nu_im fluctuates with the augment of q and the fluctuation is more acutely in partitioned enclosure.Both two kind enclosures,k shows little impact on Nu_em while Nu_im shows small change with the increase of k when?=0°.In addition,the uncertainty analysises of experimental data were investigated to ensure the creditability of this experiment.Besides,by regression analysis,correlations of Nu_im and Nu_em with?,?,V,q have been developed.Furthermore,the correlations show a good agreement with experimental data,which can be used in practical engineering application.