Techniques for the Estimation of Pressure Loss Coefficients of Bundle Junctions, Grid Spacers and Bearing Pads

Abstract

A method to calculate the loss coefficients for bundle junctions, spacers and bearing pads is presented here. The method is based on the principle of pressure loss due to sudden change in flow area. The single channel loss coefficient can be used to predict pressure drop for interconnected subchannels via the ASSERT subchannel code using appropriate correction factors. The ASSERT code is validated against experimental data for the pressure drop due to blockage in both single and interconnected subchannels. Moreover, the diversion of mass flux from a blocked to an unblocked channel is also validated against the available data using the ASSERT code. The ASSERT prediction shows very good agreement with the data.