Analysis of Flow Through the Entry Region of a Channel with Metal Foam Packing

The paper presents results of numerical simulation of fluid flow through a horizontal channel filled with AlSi7Mg alloy open-cell aluminium foam. The numerical analysis regarded adiabatic and nonadiabatic flow of air, water and machine oil. Due to the complex structure of the foam skeleton, numerical simulations were performed by application of a simplified geometrical foam model in the shape of Kelvin structure. The subject of the detailed analysis was distribution of velocity and temperature in the inlet area of the channel. The local fluid velocity demonstrates considerable variability due to the periodic changes in the cross-section of the foam cells. The impact of the wall on the velocity distribution is visible only at the distance not exceeding the diameter of a cell. The fluctuations of the fluid temperature are only discernible at the distance equal to three times the cell size. It was further stated that the hydrodynamic flow development occurs relatively quickly near the channel inlet. The distribution of the velocity is formed along a section with the length corresponding to five times the size of a foam cell while the thermal development requires a several times greater length of the channel section.