圆弧形三角翼翅片管换热器流动与传热特性的数值模拟

Flow and Heat-transfer Characteristics of Finned Tube Heat Exchanger with Arc Delta Winglets

采用三维数值模拟方法对加装圆弧形三角翼和直三角翼涡流发生器的翅片管换热器的流动与传热耦合特性进行了研究.结果表明:Re在500～5 000时,圆弧形三角翼和直三角翼均可以提高换热器的传热能力,圆弧形三角翼强化传热的效果略低于直三角翼,但其流动阻力明显小于直三角翼;换热管顺排布置时,圆弧形三角翼换热器的综合性能比直三角翼提高了7.3%～11.5%;换热管叉排布置时,圆弧形三角翼换热器的综合性能比直三角翼提高了8.2%～9.5%;涡流发生器可以使流体产生垂直于翅片方向的速度分量,改善流场中速度场和温度场的协同性,从而增强传热能力.

3D numerical simu acteristies of finned tube he show that when the Re is in lations were performed to investigate the flow and heat transfer coupling charat exchangers with arc or straight delta-winglet vortex generators. Results 500-5 000, both the arc and straight delta winglets can enhance the heat transfer of heat exchanger. The enhancement effect of arc delta winglet is slightly weaker than the straight one, but its flow resistance is obviously smaller. In comparison with straight delta-winglet exchanger, the com- prehensive performance of are delta-winglet exchanger is 7.3%-11.5% and 8.2%-9.5% higher respectively in the case of aligned and staggered arrangement of heat-exchanger tube. The vortex generator can enable fluid to generate a velocity component perpendicular to the fin direction and improve the eooperativity between velocity filed and temperature field, and therefore the heat-transfer performance is enhanced.