Gas catalytic heaters with improved temperature distribution

摘要

A gas catalytic heater having an improved temperature distribution is disclosed which includes a body having an open end in which is disposed a porous catalytically active layer containing a catalyst such as platinum metal. A sealed plenum chamber is disposed below the catalytically active layer and has a gas-permeable wall portion facing toward the active layer and a gas inlet orifice for introducing a fuel gas into the chamber. The gas-permeable wall portion may comprise a perforated metal plate having a plurality of tiny apertures the total open area of which is significantly less than that provided by perforated plates used in catalytic heaters of the prior art.