Limits of heat transfer intensification in compact heat exchangers

The limiting coefficients of heat transfer for compact heat exchangers are estimated on the basis of a two-dimensional two-temperature model of convective heat exchange in porous media. An expression is obtained which defines a physical limit on the heat transfer characteristics of cooling systems. It is shown that maximum heat transfer is achieved when water is used as coolant in combination with highly heat-conductive structural materials (e.g., copper, bronze, silicon carbide, molybdenum, and beryllium); flow rates should be a maximum and the distance between the collectors should be a minimum.