“…Although not mentioned by him, double-spiral heat exchangers of many turns would appear to have a particular advantage in high-temperature and cryogenic applications in that the external area is reduced to the outer curved surface and the end plates, thereby reducing the leakage of energy to the surroundings. Strenger et al (1990) have examined the use of a double-spiral heat exchanger for the catalytic incineration of low concentrations of contaminates, such as carbon monoxide, hydrocarbons, organic compounds, aerosols, and microorganisms, which may be present in the air of spacecraft, airliner cabins, automobiles, hospital rooms, and industrial clean rooms. In this application the heat losses from a double-pipe heat exchanger would be prohibitive despite the use of the best possible thermal insulation.…”