Heat transfer enhancement in oscillatory flow in a grooved channel
Abstract
Laminar oscillatory flow in a periodically-grooved channel is characterized by formation of a separated vortex followed by rapid ejection of the vortex at flow reversal. In this paper, the spectral element method is used to understand the fluid mechanical phenomena associated with vortex formation/ejection, and to quantify its effect on heat transfer augmentation. It is found that oscillation of the flow in a grooved channel significantly decreases the peak wall temperature (for given wall flux) relative to the non-oscillatory case. Furthermore, as vortex ejection occurs near zero mean flow, little concomitant momentum transport (i.e., increased power input) is associated with this additional heat transfer. The parametric dependence of transport enhancement by oscillatory flow over grooved walls is discussed, and a simple model is proposed for prediction of optimal frequency. The viability of oscillation in the cooling of electronic components on (intrinsically-grooved) circuit boards is evaluated in the context of geometric, flowrate, and power constraints.
- Publication:
-
AIAA, Aerospace Sciences Meeting
- Pub Date:
- January 1984
- Bibcode:
- 1984aiaa.meetY....G
- Keywords:
-
- Boundary Layer Control;
- Channel Flow;
- Grooves;
- Laminar Heat Transfer;
- Oscillating Flow;
- Vortices;
- Circuit Boards;
- Computational Fluid Dynamics;
- Cooling;
- Laminar Mixing;
- Separated Flow;
- Wall Temperature;
- Fluid Mechanics and Heat Transfer