HEAT-TRANSFER ENHANCEMENT AND DRAG BY LONGITUDINAL VORTEX GENERATORS IN CHANNEL FLOW

被引:201
作者
FIEBIG, M [1 ]
KALLWEIT, P [1 ]
MITRA, N [1 ]
TIGGELBECK, S [1 ]
机构
[1] RUHR UNIV BOCHUM,INST THERMO & FLUIDDYNAM,LEHRSTUHL WARME & STOFFUBERTRAGUNG,W-4630 BOCHUM,GERMANY
关键词
HEAT TRANSFER; AUGMENTATION; VORTEX GENERATORS;
D O I
10.1016/0894-1777(91)90024-L
中图分类号
O414.1 [热力学];
学科分类号
摘要
Triangular and rectangular longitudinal vortex generators were formed by punching small pieces out of flat plate fins so that they stuck out of the plates and formed an angle (angle of attack) with the main flow direction. The fins were mounted on to of each other to form channels, each representing an idealization of a gas-side element of a compact heat exchanger. The effects of single-vortex generators on flow structure, flow losses, and heat transfer were investigated. The vortex structure was observed, the drag-a measure of flow losses-was measured by a balance, and the local heat transfer coefficient was obtained from unsteady liquid crystal thermography. Vortex generator geometry, angle of attack, and Reynolds number were varied. Stable longitudinal vortices were found up to much higher angles of attack than for corresponding wings in a free stream. The drag induced by the vortex generators was found to be proportional to the projected area and independent of the shape and the Reynolds number. Local heat transfer augmentation of several hundred percent and mean heat transfer enhancement of more than 50% over an area more than 50 times the vortex generator area were achieved. The heat transfer enhancement per unit vortex generator area was highest for delta wings followed by delta winglets and rectangular winglets.
引用
收藏
页码:103 / 114
页数:12
相关论文
共 12 条
[1]  
Pearcy, Shock-Induced Separation and Its Prevention, Boundary Layer and Flow Control, 2, pp. 1166-1344, (1961)
[2]  
Edwards, Alker, The Improvement of Forced Surface Heat Transfer Using Surface Protrusions in the Form of Cubes and Vortex Generators, Fifth Int. Heat Transfer Conf., pp. 244-248, (1974)
[3]  
Russel, Jones, Lee, Transfer Enhancement Using Vortex Generators, Seventh Int. Heat Transfer Conf., pp. 283-288, (1982)
[4]  
Turk, Junkhan, Heat Transfer Enhancement Down-stream of Vortex Generators on a Flat Plate, Eighth Int. Heat Transfer Conf., pp. 2903-2908, (1986)
[5]  
Eibeck, Eaton, The Effects of Longitudinal Vortices in A Turbulent Boundary Layer on Momentum and Thermal Transport, Eighth Int. Heat Transfer Conf., pp. 1115-1120, (1986)
[6]  
Eibeck, Eaton, Heat Transfer Effects of a Longitudinal Vortex Embedded in a Turbulent Boundary Layer, J. Heat Transfer, 109, pp. 16-24, (1987)
[7]  
Fiebig, Kallweit, Mitra, Wing Type Vortex Generators for Heat Transfer Enhancement, Eighth Int. Heat Transfer Conf., pp. 2909-2914, (1986)
[8]  
Kallweit, Längswirbelerzeuger für den Einsatz in Lamellenwärmetauschern, Dissertation, (1986)
[9]  
Hummel, On the Vortex Formation Over a Slender Wing at Larger Angles of Incidence, AGARD-CCO-247, 15/1–15/7, (1978)
[10]  
Delery, Horowitz, Leuchter, Solignac, Fundamental Studies on Vortex Flow, Res. Aerospace, 2, pp. 1-24, (1984)