Abstract: The invention presents a MONOBLOC fin and plate heat exchanger design preventing internal leakages and intermixing of high-temperature and low-temperature flows, e.g. oil and fuel. This is achieved through a particular configuration of the heat exchanger, whereby its core assembly is completely or partially produced from a one-piece monolithic metallic block. Owing to that, all brazed seams, which in conventional fin and plate heat exchangers contact with both hot medium and cold medium flows, are fully abolished thereby excluding a source for imperfections usually developing in brazed joints and base metal in the process of pressure-temperature cyclic loading. Employing custom-made individual fins allows about two-fold increase in the strength of brazed joints in comparison with ordinary corrugated fins (due to doubling of the brazed surface).

Abstract: An air cycle air conditioning system including a turbine for receiving air and providing expansion thereof, thus lowering the temperature and pressure of the air, an air--air heat exchanger defining a first air flow path for air to be cooled and a second air flow path for air from the turbine at sub-atmospheric pressure to pass therethrough and absorb heat from the air to be cooled, and a compressor, at least partially driven by the turbine, for drawing air at sub-atmospheric pressure through the second flow path for air, characterized by a pre-heater which heats a flow of air, preferably comprising a mixer of ambient air and recirculation air, and directs this mixed flow to the air--air heat exchanger, thereby increasing its temperature and, as a result, the outlet temperature of the secondary air flow, thereby increasing its water vapor absorption capacity.

Abstract: A heat exchanger including a plurality of heat transfer elements defining hot and cold fluid flow paths with inlet and outlet ends for flow therethrough of a relatively hot fluid and a relatively cold fluid respectively, the hot and the cold fluid flow paths each having at least one portion substantially parallel to each other in which the relatively hot fluid and the relatively cold fluid flow in a common direction such that a thermal resistance between the plurality of heat transfer elements and the flow of the fluids therethrough, and a temperature difference between the hot and the cold fluid flow paths, are maintained over a portion of the heat exchanger to substantially prevent freezing of at least one component of either of the relatively hot fluid and the relatively cold fluid.

Abstract: An air cycle air conditioning system including an air-air heat exchanger defining a first air flow path for air to be cooled and a second air flow path for air to pass therethrough and absorb heat from the air to be cooled and apparatus for supplying air to the second air flow path at sub-atmospheric pressure.

Abstract: An improved rotor blade arrangement pivotally mounted in a cylindrical recess in the rotor. The blade arrangement is pivotally mounted on a blade support and has a center of gravity offset from the pivot mounting. The arrangement includes a pair of arcuate sections joined at a blade tip, which tip seals against the stator. Each arcuate section has a free end opposite the blade tip including a linear seal contacting the recess surface. The resulting arrangement minimizes the friction loses of the blade arrangement and forms a sealed space between the recess surface and the blade profile to enhance the compression ratio for compressible fluids.