Pressure drop and heat transfer in an isothermal channel with impinging flow

The performance of air-cooled plate-fin heat sinks in impinging flow differs significantly from that of similar heat sinks in parallel flow. A numerical experiment and analytical scaling has been carried out to determine the pressure drop and thermal performance of single isothermal channels with variable-width impinging flow. The flow enters the channel normal to the heat sink base. The pressure drop and thermal performance of the flow in this configuration are particularly important for analyzing plate-fin heat sinks for which axial fans supply the flow, since the fan flow rate varies with the static pressure. The results of the numerical experiment and scaling are combined into dimensionless correlations for pressure loss coefficient and channel average Nusselt number. These correlations may then be used to predict the thermal performance of the heat sink.