应用流场协同理论的多纵向涡强化换热管

Tubes with Heat Transfer Property Intensified by Multi-longitudinal Vortices According to the Field Coordination Theory

应用流场协同理论研发了两种多纵向涡强化换热管--不连续双斜向内肋管和交叉缩放椭圆管,分析了其强化换热的物理机制.数值模拟和实验结果表明,当Re=500-2300时,与考虑进口段效应的圆形截面管(L/D=300)相比,不连续双斜向内肋管的换热增强250%～650%,阻力增加120%-300%;交叉缩放椭圆管Nu可提高200%～500%,沿程阻力增加100%～350%;当Re=2300～5×104时,与圆管相比,不连续双斜向内肋管换热可增强110%～240%,阻力增加120%～240%;交叉缩放椭圆管换热可增强35%～170%,阻力增加130%～160%.两种新型强化换热管具有优良的换热性能,可广泛应用于电力、石化、建筑供热等行业.

Two kinds of tubes with heat transfer properties, intensified by multi-longitudinal vortices, i.e. tubes with discrete double inclined ribs (DDIR) and with alternating elliptical axes (AEA), have been developed and their physical mechanism of heat transfer intensification analyzed. Numerical simulation and experimental results show, that in the range of Re = 500-2300, heat transfer in DDIR tubes is raised by 250%-650%, with flow resistance increased by 120%-300%, while in AEA tubes their respective increase is 200%-500%, and 100%-350%, compared to circular tubes (L/D = 300) with entrance effect included; in the range of Re = 2300-5 × 104, as compared with circular tubes, the increase of heat transfer is 110%-240% and that of flow resistance 120%-240% in DDIR tubes while in AEA tubes the respective increase is 35%-170% and 130%-160%. The performance of these two kinds of tubes with intensified heat transfer property is excellent and there may be a broad field of application in the power, petrochemical and building industry for heating purposes.