Heat pump/refrigerator using liquid working fluid

A heat pump or refrigerator apparatus comprising:

• first and second heat exchangers, each having a pair of working fluid-carrying passages interconnected at a first end of the exchanger and unconnected at the other end of the exchanger to form a pair of ports;
• a regenerator forming primarily parallel first and second passages which are physically separated but closely thermally coupled at numerous locations along the passages, said regenerator having check valve means allowing flow only in one direction through the other passage, said passages each having first ends coupled respectively to the pair of ports of said first heat exchanger and said passages having second ends that are coupled respectively to the pair of ports of said second heat exchanger;
• a displacer having a first end connected to the first end of said first heat exchanger, said displacer having a second end connected to the first end of said second heat exchanger, said displacer also having a reservoir at each of its ends and having means for moving fluid at constant volume out of the reservoir at one end while receiving fluid at the reservoir at the other end;
• a quantity of working fluid lying in said heat exchangers, regenerator and displacer, said fluid being a liquid;
• and
• compressor means for alternately compressing and expanding said liquid working fluid.

A method for pumping heat from a heat source into a heat sink comprising:

• flowing working fluid primarily under high pressure into a first end of a displacer, while also flowing said fluid in a first direction through a first passage of a regenerator;
• reducing the pressure of said fluid to lower its temperature;
• flowing said fluid while primarily under low pressure from said first end of said regenerator through a first heat exchanger which is coupled to the heat source to increase the temperature of the fluid, while also flowing said fluid in a second direction through a second passage of the regenerator and exchanging heat with fluid in the first passage by heat conduction largely in a direction perpendicular to the lengths of said passages, and while also flowing said fluid in a second direction through a second passage of the regenerator and exchanging heat with fluid in the first passage by heat conduction largely in a direction perpendicular to the lengths of said passages, and while also flowing said fluid into a second end of said displacer;
• increasing the pressure of said fluid to increase its temperature;
• flowing said fluid primarily while under high pressure from said second end of said regenerator through a second heat exchanger which is coupled to the that sink to decrease the temperature of the fluid;
• said fluid flowing in a liquid phase through said heat exchanger, regenerator passages, and the ends of said displacer, and said step of increasing the pressure including applying a maximum pressure of at least about 1000 psi above saturated pressure to said liquid fluid.

A method of air conditioning an indoor environment to keep it at a temperature of about 70.degree. F. by pumping heat into a higher temperature heat sink which is in a range (such as on the order of 100.degree. F. but extending downward to the desired indoor temperature) which is normally encountered outdoors, comprising:

• circulating a fluid back and forth between a sink displacer reservoir and a source displacer reservoir, by way of a sink heat exchanger which is thermally coupled to said higher temperature heat sink, alternate one-way passages of a regenerator, and a source heat exchanger which is thermally coupled to said indoor environment;
• pressurizing said fluid primarily after flowing it into said sink reservoir, to raise the temperature of fluid in the sink reservoir above that of the heat sink, and relieving said pressure primarily after flowing said fluid into said source reservoir to lower the temperature of fluid in the source reservoir, said step of circulating including flowing the pressurized fluid in the sink reservoir through the sink heat exchanger and flowing the pressure-relieved fluid in the source reservoir through the source heat exchanger;
• said step of circulating a fluid by way of alternate one-way passages of a regenerator, including flowing heat along primarily parallel passages and exchanging heat between fluids at adjacent locations along the two passages;
• and
• said step of circulating a fluid including circulating a liquid in solely a liquid phase between said reservoirs, wherein said liquid is of type which has a temperature coefficient of expansion of at least 1.times.10.sup.-3 per .degree.K. at 70.degree. F. and 1000 psi, and said step of pressurizing including applying a maximum incremental pressure of at least about 1000 psi.

A method for heating an indoor environmemt heat sink to keep it at a temperature of about 70.degree. F. by pumping heat from a lower temperature heat source which is in a range (e.g. on the order of 40.degree. F. but extending upward to the desired indoor temperature) that may be encountered outdoors, comprising:

• circulating a fluid back and forth between a sink displacer reservoir and a source displacer reservoir, by way of a sink heat exchanger which is thermally coupled to said indoor environment, alternate one-way passages of a regenerator and a source heat exchanger which is thermally coupled to said lower temperature heat source;
• pressurizing said fluid primarily after flowing it into said sink reservoir to raise the temperature of fluid in the sink reservoir above that of the heat sink, and relieving said pressure primarily after flowing said fluid into said source reservoir to lower the temperature of fluid in the source reservoir below that of the heat source, said step of circulating including flowing the pressurized fluid in the sink reservoir through the sink heat exchanger and flowing the pressure-relieved fluid in the source reservoir through the source heat exchanger;
• said step of circulating a fluid by way of alternate one-way passages of a regenerator, including flowing heat along primarily parallel passages and exhanging heat between fluids at adjacent locations along the two passages;
• and
• said step of circulating a fluid including circulating a liquid in solely a liquid phase between said reservoirs wherein said liquid is of a type which has a temperature coefficient of expansion of at least 1.times.10.sup.-3 per .degree.K. at 70.degree. F. and 1000 psi, and said step of pressurizing including applying a maximum pressure increment of at least about 1000 psi.

A heat pump apparatus comprising:

• a plurality of heat pump units, each having
• a pair of displacer reservoirs;
• means for flowing a working fluid from a first reservoir through a first heat exchanger and into the second reservoir and then flowing fluid from the second reservoir through the second heat exchanger to the first reservoir, and
• means for compressing all of the working fluid after flowing some fluid into said first reservoir but before flowing most of the fluid therein through said first heat exchanger, and for relieving the pressure on all of the working fluid after flowing fluid into said second reservoir but before flowing most of the fluid therein through said second heat exchanger;
• and wherein the means for compressing and relieving the pressure in each of said pump units, includes
• a compression cylinder and a compressing piston moveable in said cylinder, and with the cylinder coupled to the working fluid to pressurize and expand it as the piston moves;
• a motor-driven crank member;
• and
• means for connecting the pistons of said plurality of pump units to said crank member to operate them out of phase with one another so that as one piston is moving in a direction to relieve pressure it supplies work tending to rotate said crank member, and at the same time at least one other piston is being moved by said crank member to compress fluid in its pump unit.

A heat transfer apparatus comprising:

• a hydraulic motor having high and low pressure ends;
• a hydraulic pump having high and low pressure ends;
• first and second heat exchangers, each having opposite ends;
• a regenerator having first and second passages which are thermally coupled;
• said hydraulic motor and pump, heat exchangers, and regenerator being interconnected, to permit the flow of a working fluid into the low pressure end of the hydraulic pump, out of the high pressure end of the pump through a first passage of said regenerator to the high pressure end of said hydraulic motor, and from the low pressure end of said hydraulic motor through the second heat exchanger and through the second passage of said regenerator to the low pressure end of said hydraulic pump;
• drive motor means coupled to said hydraulic pump to help drive it and coupled to said hydraulic motor to enable the hydraulic motor to help drive the hydraulic pump;
• a working fluid which is in a liquid phase in said hydraulic motor and pump, heat exchangers and regenerator.