Surface heat exchangers
Abstract
The paper analyzes the parameters involved in the design of a surface heat exchanger which would meet given requirements, with particular reference to the advantages, in terms of fuel penalty, over conventional ram air coolers. The discussion is limited to air-air surface heat exchangers which appear to have received much less attention than their air-oil or air-water counterparts. The surface heat exchanger is viewed as a thin duct of rectangular cross section with internal corrugation through which flows the fluid to be cooled. Cooling is achieved by heat rejection through the outer wall of the duct to the adjacent colder boundary layer. It is shown that the performance of a surface heat exchanger can be increased by reducing both the width of the cooler and the depth of the internal corrugation and by using external fins. Replacement of a conventional heat exchanger by an equivalent surface cooler would result in a substantial saving in fuel, depending on flight conditions.
- Publication:
-
Aeronautical Quarterly
- Pub Date:
- February 1976
- Bibcode:
- 1976AeQ....27...40L
- Keywords:
-
- Cooling Fins;
- Design Analysis;
- Heat Exchangers;
- Surface Cooling;
- Fuel Consumption;
- Graphs (Charts);
- Heat Transfer Coefficients;
- Military Aircraft;
- Passenger Aircraft;
- Fluid Mechanics and Heat Transfer