Numerical and experimental investigation of a pressed-fit 10 PPI aluminium foam heat exchanger

A comprehensive experimental and numerical comparison on the thermo-hydraulic behaviour of a prototype fin-and-tube heat exchanger made of 10 PPI open-cell aluminium foam is performed. Heat transfer and pressure drop are first measured through an open wind tunnel experiment with free stream air velocities between 1.1 and 3.1 m/s, corresponding the velocity range of an HVAC unit. The heat exchanger is a so-called low capacity unit, meaning that some tubes are not conducting any water. This results in a non-uniform temperature profile at the outlet and represents a good case to compare with a numerical model (based on the volume averaging theory). The comparison of the experimental results with the numerical ones is made in 2D. Both computed heat transfer and pressure drop agree well with the experimental data, respectively within 3% and the measurement error of the pressure drop transducer. Once the numerical model is implemented, it takes less than one hour on 12 cores to calculate the heat transfer rate of a heat exchanger with foam at one velocity set point, making it very interesting for future study/optimisation of heat exchangers with metal foam