摘要:
A refrigeration system includes a compressor for driving a refrigerant along a flow path in at least a first mode of system operation; a first heat exchanger along the flow path downstream of the compressor in the first mode; a second heat exchanger along the flow path upstream of the compressor in the first mode; and a pressure regulator or expansion device in the flow path downstream of the first heat exchanger and upstream of the second heat exchanger in the first mode, wherein the first heat exchanger is positioned within a housing which defines a flow path for heat exchange fluid and the housing defines a zone of reduced flow area along the flow path, and wherein the first heat exchanger is positioned in the zone of reduced flow area.
摘要:
A refrigeration system includes a compressor for driving a refrigerant along a flow path in at least a first mode of system operation; a first heat exchanger along the flow path downstream of the compressor in the first mode; a second heat exchanger along the flow path upstream of the compressor in the first mode; and an expansion device in the flow path downstream of the first heat exchanger and upstream of the second heat exchanger in the first mode, wherein the second heat exchanger includes a combined header and accumulator for collecting liquid and vapor refrigerant.
摘要:
A refrigeration system includes a compressor for driving a refrigerant along a flow path in at least a first mode of system operation; a first heat exchanger along the flow path downstream of the compressor in the first mode; a second heat exchanger along the flow path upstream of the compressor in the first mode; and a pressure regulator or expansion device in the flow path downstream of the first heat exchanger and upstream of the second heat exchanger in the first mode, wherein the first heat exchanger comprises a plurality of heat exchanger components arranged along a flow path of heat exchange fluid for the first heat exchanger. The heat exchanger components can be positioned in smaller available areas within the unit and thereby use space more efficiently.
摘要:
A bottle cooler system (20, 70, 100) includes a compressor (22), a first heat exchanger (24) and a second heat exchanger (28). In a cooling mode of operation, the second heat exchanger is downstream of the first heat exchanger and upstream of the compressor to cool contents of an interior volume. In a defrost mode of operation, refrigerant in the second heat exchanger is used to defrost an ice build-up on the second heat exchanger.
摘要:
A refrigeration system includes 0 compressor for driving 0 refrigerant along flow path in at least a first mode of system; a first heat exchanger along the flow path downstream of the compressor in the first mode; a second heat exchanger along the flow path upstream the compressor in the first mode; and a pressure regulator or expansion device in the flow path downstream of the first heat exchanger and upstream of the second heat exchanger in the first mode, wherein at least one of the first heat exchanger and the second heat exchanger comprises a flat tube heat exchanger.
摘要:
An expensive expansion device may be eliminated in favor of a less expensive pressure regulator in a CO2 vapor compression system such as is used in a bottle cooler or small-capacity air conditioner, refrigerator, or other system.
摘要:
A heat pump, and in particular a heat pump for heating a hot water supply is provided with an improved defrost mode. The defrost mode is actuated to remove frost from an outdoor evaporator that may accumulate during cold weather operation. An algorithm for operation of the defrost mode is developed experimentally by seeking to maximize the heat transfer provided by the refrigerant. A heating system condition is experimentally related to the heat transfer capacity. One then maximizes the average heat transfer capacity to determine the optimum initiation point for the defrost mode. Further, protections are included into the defrost mode. When the heat pump is utilized to heat hot water, methods are provided to prevent the water that remains in the heat exchanger from becoming unduly heated. In one method, the water pump may be periodically operated to move the water. In a second method, a control ensures the discharge pressure of the refrigerant leaving the compressor is reduced, and that the water pump is not stopped until that reduced temperature falls below a predetermined maximum. The temperature reduction is achieved through a dual control loop wherein a temperature that is too high results in a new desired discharge pressure. The control achieves the new desired pressure by controlling the expansion device. In another protection feature, as a control determines that the defrost mode is nearing its end, an evaporator fan is run to remove melted water from the evaporator coils, and also to ensure the refrigerant leaving the evaporator does not reach unduly high pressure or temperatures.
摘要:
A vapor compression system includes a compressor, a gas cooler, an expansion device, and an evaporator. Refrigerant is circulated through the system. The high side pressure of the vapor compression system is selected to optimize the heating capacity. In one example, the optimal high side pressure is obtained by determining the high side pressure that correlates to the maximum current required to operate to the water pump. In another example, the actual temperature of the water entering the gas cooler, the water exiting the gas cooler, and the ambient air temperature are measured and compared to a predetermined value to determine the optimal high side pressure.