脉动流下贝塞尔曲线型波纹壁通道流动传热特性研究

To study the spatiotemporal effect of heat transfer enhancement in the channel under the coupling effect of corrugated structure and pulsating flow, three kinds of corrugated wall channels are designed based on the advantages of changeability, flexibility and easiness to control of Bezier curves in this study and their flow and heat transfer characteristics under different flow and pulsation parameters and the mechanism of design factors are compared and analyzed. The results show that under turbulent flow conditions(Re=5 000, 10 000, and 20 000), the model 2 channel with the smallest head-on area has the smallest flow resistance, and the model 4 channel with concave and convex structures has the best heat transfer enhancement effect. With the increase of the pulsation frequency(2-20 Hz), the comprehensive thermal performance of the three model channels first increases and then decreases. And with the increase of the pulsation amplitude(0.1-0.9), the comprehensive thermal performance of the three model channels first increases and then slightly decreases. Under the combined impact of the pulsating flow and the wall structure, the development of the thermal boundary layer is further destroyed within the scale of the structural unit, and the high-temperature working fluid region is discontinuously distributed along the flow direction. The spatiotemporal coupling effect of fluid disturbance in the corrugated wall channel under pulsating flow significantly improves the comprehensive thermal performance of the channel, and provides an effective way to solve the problem of overheating in the narrow channel.