Effect of Component Layout and Geometry on the Flow Distribution in Electronic Circuit Packs

An experimental investigation was under taken to quantify the effect of component size, geometry and layout on fluid flow distribution in electronic circuit packs. The study was conducted in a water tunnel with ink as the flow visualization vehicle. Two Reynolds numbers of 1600 and 2300, based on channel hydraulic diameter, were considered. Several component layout and geometries were used to quantify their impact on flow distribution. The components were three dimensional and comparison was made with the previous studies where the component and channel widths were equal - effectively two dimensional components. The study revealed that the flow is highly three dimensional and tends to be periodic in nature. Similar flow structures were obtained from components of similar shape. When the component geometry is mixed on the board, several flow regimes coexists inside the channel. In general, the flow structure observed inside the channel was periodically laminar with localized turbulence caused by vortex breakdown.