Abstract:

The unsteady, thermally stratified flow in the neighborhood of an idealized stack is simulated using a nonlinear two-dimensional model. The model relies on a vorticity-based formulation of the compressible conservation equations in the low-Mach-number and short-stack limits. The action of the acoustic standing wave is represented in terms of oscillating velocity conditions, and heat exchangers are modeled by maintaining the temperature at the cold and hot ends of the stack at fixed, constant values. Simulations are used to visualize the unsteady velocity and temperature fields, and to analyze the dependence of the ``steady-state'' cooling load on the drive ratio and the length of the heat exchangers. [Work of ASW and OMK supported by the Office of Naval Research. RK is partially supported by Deutsche Forschungsgemeinschaft (DFG).]