A transcritical vapor compression system includes a fluid circuit circulating a refrigerant in a closed loop. The fluid circuit has operably disposed therein, in serial order, a compressor, a first heat exchanger, at least one non-variable expansion device and a second heat exchanger. The compressor compresses the refrigerant from a low pressure to a supercritical pressure. The first heat exchanger is positioned in a high pressure side of the fluid circuit. The second heat exchanger is positioned in a low pressure side of the fluid circuit. The at least one non-variable expansion device reduces the pressure of the refrigerant from a supercritical pressure to a relatively lower pressure. A refrigerant storage vessel is in fluid communication with the fluid circuit and contains a variable mass of refrigerant whereby the capacity of the system may be controlled.

Transcritical vapor compression system and method of operating including refrigerant storage tank and non-variable expansion device

Aspects of the disclosure generally provide a heat engine system and a method for regulating a pressure and an amount of a working fluid in a working fluid circuit during a thermodynamic cycle. A mass management system may be employed to regulate the working fluid circulating throughout the working fluid circuit. The mass management systems may have a mass control tank fluidly coupled to the working fluid circuit at one or more strategically-located tie-in points. A heat exchanger coil may be used in conjunction with the mass control tank to regulate the temperature of the fluid within the mass control tank, and thereby determine whether working fluid is either extracted from or injected into the working fluid circuit. Regulating the pressure and amount of working fluid in the working fluid circuit selectively increases or decreases the suction pressure of the pump to increase system efficiency.

Heat Engine and Heat to Electricity Systems and Methods with Working Fluid Mass Management Control

A system for converting thermal energy to work. The system includes a working fluid circuit, and a precooler configured to receive the working fluid. The system also includes a compression stages and intercoolers. At least one of the precooler and the intercoolers is configured to receive a heat transfer medium from a high temperature ambient environment. The system also includes heat exchangers coupled to a source of heat and being configured to receive the working fluid. The system also includes turbines coupled to one or more of the heat exchangers and configured to receive heated working fluid therefrom. The system further includes recuperators fluidly coupled to the turbines, the precooler, the compressor, and at least one of the heat exchangers. The recuperators transfer heat from the working fluid downstream from the turbines, to the working fluid upstream from at least one of the heat exchangers.

Heat engine cycles for high ambient conditions

The present invention generally relates to a system that enables one to address various thermal management issues in advanced gas turbine engines. In one embodiment, the present invention relates to a method to extract heat from an air stream, utilize a significant fraction for on-board power generation, and reject a small quantity of heat to the fuel stream safely at, for example, a lower temperature. In another embodiment, the present invention relates to a method to extract heat from an air stream, utilize a significant fraction for on-board power generation, and reject a small quantity of heat to the fuel stream safely at, for example, a lower temperature with no potential air/fuel contact is disclosed.

System and method for managing thermal issues in gas turbine engines

Various thermodynamic power-generating cycles are disclosed. A turbopump arranged in the cycles is started and ramped-up using a starter pump arranged in parallel with the main pump of the turbopump. Once the turbopump is able to self-sustain, a series of valves may be manipulated to deactivate the starter pump and direct additional working fluid to a power turbine for generating electrical power.

Driven Starter Pump and Start Sequence

There is disclosed an novel refrigeration apparatus and a method of refrigeration. The novel refrigeration apparatus comprises a desorber/evaporator, a gas/liquid compressor operatively connected to said desorber/evaporator, a resorber/condenser operatively connected to said gas/liquid compressor, an expansion device operatively connected to said resorber/condenser and to said desorber/evaporator and a circulating refrigerant comprising carbon dioxide and a liquid co-fluid in which the carbon dioxide is differentially soluble. The refrigeration method comprises compressing carbon dioxide gas and a liquid co-fluid in a gas/liquid compressor to an increased pressure, such that carbon dioxide at least partially dissolves in the liquid co-fluid, and reducing the pressure on the liquid co-fluid containing the dissolved carbon dioxide so that dissolved carbon dioxide comes out of solution with the liquid co-fluid, and recirculating the gaseous carbon dioxide and liquid co-fluid to the gas/liquid compressor.

Hans O. Spauschus

Papers

Reduced pressure carbon dioxide-based refrigeration system