Research On Heat Transfer Enhancement Characteristics Of Regenerative Corrugated Plate With Perforations

In order to improve the heat transfer efficiency of regenerative heat exchanger and alleviate the problem of ash accumulation, the heat transfer components (the thermal storage type corrugated plates) of the regenerative heat exchanger need to be reformed. In this paper, the method of adding a disturbing flow hole on the heat transfer element is presented, and the heat transfer element is analyzed from various aspects.Transient test method (single-blow technology) was also used to study the performance heat transfer elements corrugated plate with perforations at three kinds of arrangement angles(15°,30°, 45°). Exergy loss was adopted to investigate the heat transfer elements with perforations. The results show that the Nusselt number for perforations(15°,30°,45°)is 17.1%,24.8%,34.9% higher than that without perforations, respectively; The friction factor for perforations is 24.7%,33.1%,38.4% super than that without perforations, respectively. Performance comparisons with the heat transfer elements without perforations at equal pumping power show that arrangement angles at 45° gives the best performance. The Nu/Nuo of arrangement angles at 45° is 53.3%,67.8% higher than arrangement angles at 15° and 30°.For evaluating the performance of heat transfer enhancement, exergy analysis was adopted to investigate the heat transfer elements with perforations. The exergy analysis calculation formula was expanded from the steady heat transfer to the transient heat transfer. Exergy loss curve and exergy loss coefficient curve are obtained by using the experimental data. The exergy loss curve and exergy loss coefficient both have a turning point. The turning point is derived from the transition state that has violent irregular intense motions. The turning point can be expressed as the critical point of transition state to fully turbulent. A serious waste of energy happens near the turning point. In practical application a heat transfer member should avoid the turning point to reduce the wasting energy.Numerical simulation was used to study the performance of three radius of curvature. The flow fields and heat transfer characteristics were simulated. The velocity field and temperature field under different are obtained. The results of the study show that after opening spoiler holes, channel air was disturbed, resulting in more uniform channel flow velocity distribution and the temperature distribution, and enhancement of heat transfer. Separation method was used to analyzed the resistance and heat transfer performance alteration caused by the perforations form the theoretical view. Among three situations where spoiler aperture were 7,8,9mm,9mm has the best strengthening heat transfer performance. The effect of heat transfer performance enhancement of ripple curvature radius could only be assessed together with the spoiler aperture.