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Three-dimensional finite-element simulation of a turbulent push-pull ventilation system.

M R Flynn·K Ahn·C T Miller
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Abstract

A finite-element formulation with penalty approach to enforce continuity is employed here to simulate the three-dimensional velocity field resulting from a simple push-pull ventilation configuration. An analytic expression for the length scale and a transport equation for turbulent kinetic energy are coupled with the momentum equations. A coaxial square hood and jet are arranged with cross-draught perpendicular to the common centreline. Numerical predictions of the velocity and turbulence kinetic energy fields are evaluated in the plane of symmetry with hot film anemometry, and smoke-wire flow visualizations. The agreement of the simulated jet trajectories with flow visualizations is reasonable, as are velocities. Predictions of turbulence kinetic energy are not as good, particularly near the hood face. Despite the limitations the numerical approach is useful in assessing the impact of cross-draughts on the push-pull arrangement.

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AirMathematicsMotionVentilationJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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M R Flynn, K Ahn, C T Miller. 1995. Three-dimensional finite-element simulation of a turbulent push-pull ventilation system.. https://doi.org/10.1016/0003-4878(95)00029-e

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