Abstract: Cooling systems include a cold sink thermally coupled to a heat load, a separator configured to separate liquid and vapor portions of a working fluid, and a cooling cycle having a vapor loop and a liquid loop, the cooling cycle having the working fluid configured to pass through both the vapor loop and the liquid loop. The vapor loop includes the separator, a compressor, a condenser, and a valve. A vapor form of the working fluid flows from the separator into the compressor, and the working fluid then flows to the condenser, and then through the valve, and returned to the separator. The liquid loop includes the cold sink, the separator, and a pump. A liquid form of the working fluid flows from the separator into the pump and the working fluid is increased in pressure and supplied to the cold sink and then returned to the separator.

Abstract: Cooling systems include a cold sink having a number of heat load cooling paths and a heat load associated with each cooling path. An inlet is configured to supply a cooling fluid into the cold sink and an outlet is configured to receive the cooling fluid after passing through the plurality of heat load cooling paths of the cold sink. A pressure regulating element is arranged along each cooling path, each pressure regulating element arranged between the inlet and the heat load along each cooling path and configured to cause a pressure drop in the cooling fluid prior to passing the cooling fluid to each heat load. The pressure drop caused by each pressure regulating element is the same and is a pressure drop greater than a maximum pressure drop across each heat load of a system without such pressure regulating elements.