Abstract: An electronic substrate is formed of a porous planar heat exchanger and an orifice plate overlying and thermally contacting the heat exchanger. The orifice plate has a plurality of apertures therethrough. An electronic device is mounted to the orifice plate. A coolant such as air or other gas is forced through the heat exchanger and the apertures of the orifice plate to remove heat that is generated by the electronic device. Preferably, at least two of the assemblies formed of the substrate and the mounted electronic device are mounted in a facing relationship to form a multichip module. A housing is provided to support the assemblies and to channel the flow of coolant through the substrates. Electrical interconnection between the components is provided by a peripheral ring with electrically conducting paths therethrough, which ring extends between the facing substrates.

Abstract: The wedge clamp (28) engages on the end of a heatsink (18) and engages within a channel shaped recess (24, 26) in the coldwall. The wedge clamp (28) is made up of a pair of wedges (32, 34) of the same angle driven together by a screw (48). This forces the wedge clamp surfaces (32, 34) apart to obtain a large heat transfer area and intimate contact with the coldwall surfaces (24, 26).

Abstract: A high concentration gradient across a solvent permeable membrane (20), separating the solution and solvent reservoirs (12, 16) or an osmotic pumped heat pipe (10), is effected by inducing convection currents across the membrane material on its solution reservoir side (34). The induced convection current is created by the difference in densities of rich and lean solute-solvent mixtures which are caused respectively to traverse separate paths (40, 42). These convection currents sweep and mix with the solvent which has been freshly pumped through the membrane from the solution reservoir side (34).

Abstract: A bubble (32) of non-condensable gas between a solvent permeable membrane (18) and solvent within a solvent reservoir (16) limits the amount of surface area of the membrane wettable by the solvent and thereby limits the amount of solvent capable of passing through the membrane into the solution reservoir (12).