A parametric investigation of natural ventilation flow with a line heat source

Abstract

The effects of Reynolds number ($\Reyn$) and Prandtl number ($\Pr$) on fully-developed, transitional natural ventilation flow with a line heat source are investigated using two dimensional direct numerical simulations. The flow is simulated in the range, $5.0\times10^5\leq \Reyn\leq 1.58\times10^6$ and $0.7\leq \Pr\leq 70$. The initial development of the flow is also investigated and scaling relationships are obtained for initial peak velocity, time taken to reach the initial peak and time taken for the onset of instability. Spectral amplitudes are shown to reduce with increasing~$\Pr$. In lower~$\Pr$ flows, large amplitude motions occur at higher frequencies than for higher~$\Pr$. The interface height is found to vary with the parameter values, and the upper layer temperature distribution is found to be more uniform at lower~$\Pr$. References

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