A monolithic heat exchanger body for inputting heat to a closed-cycle engine includes heating walls and heat sink, such as heat transfer regions. The heating walls are configured and arranged in an array of spirals or spiral arcs relative to a longitudinal axis of an inlet plenum. Adjacent portions of the heating walls respectively define corresponding heating fluid pathways fluidly communicating with the inlet plenum. At least a portion of the heat sink is disposed about at least a portion of the monolithic heat exchanger body. The heat sink includes working-fluid bodies including working-fluid pathways that have a heat transfer relationship with the heating fluid pathways. Respective ones of the heat transfer regions have a heat transfer relationship with a corresponding semiannular portion of the heating fluid pathways. Respective ones of the heat transfer regions include working-fluid pathways fluidly communicating between a heat input region and a heat extraction region.

A monolithic heat exchanger body for inputting heat to a closed-cycle engine includes heating walls and heat sink, such as heat transfer regions. The heating walls are configured and arranged in an array of spirals or spiral arcs relative to a longitudinal axis of an inlet plenum. Adjacent portions of the heating walls respectively define corresponding heating fluid pathways fluidly communicating with the inlet plenum. At least a portion of the heat sink is disposed about at least a portion of the monolithic heat exchanger body. The heat sink includes working-fluid bodies including working-fluid pathways that have a heat transfer relationship with the heating fluid pathways. Respective ones of the heat transfer regions have a heat transfer relationship with a corresponding semiannular portion of the heating fluid pathways. Respective ones of the heat transfer regions include working-fluid pathways fluidly communicating between a heat input region and a heat extraction region.

A system for energy conversion, the system including a closed cycle engine containing a volume of working fluid, the engine comprising a first chamber defining an expansion chamber and a second chamber defining a compression chamber each separated by a piston attached to a connection member of a piston assembly, and wherein the engine comprises a heater body in thermal communication with the first chamber, and further wherein the engine comprises a cold side heat exchanger in thermal communication with the second chamber, and wherein a third chamber is defined within the piston, wherein the third chamber is in selective flow communication with the first chamber, the second chamber, or both.

Embodiments described herein relate to a heat exchanger for abating compounds produced in semiconductor processes. When hot effluent flows into the heat exchanger, a coolant can be flowed to walls of a fluid heat exchanging surface within the heat exchanger. The heat exchanging surface can include a plurality of channel regions which creates a multi stage cross flow path for the hot effluent to flow down the heat exchanger. This flow path forces the hot effluent to hit the cold walls of the fluid heat exchanging surface, significantly cooling the effluent and preventing it from flowing directly into the vacuum pumps and causing heat damage. Embodiments described herein also relate to methods of forming a heat exchanger. The heat exchanger can be created by sequentially depositing layers of thermally conductive material on surfaces using 3-D printing, creating a much smaller footprint and reducing costs.

A grey water heat recovery apparatus has first and second passes in counter-flow orientation. The hot side is grey water. The cold side is fresh water. It extracts heat from the grey water. The fresh water is carried in tubing bundles in series immersed in grey water sumps in cylindrical plastic, mild steel, or stainless steel pipe. Both ends of the fresh water bundle assembly extend from the same upper end pipe closure, without a pressurized line wall penetration in the walls of the pipe. There is a non-electrically conductive barrier between the fresh water and grey water flow paths. The apparatus has a leak detection circuit and co-operable bypass valves. The tube bundle is wider at the top than at the bottom. The lower manifold has grey water passages between the centering ears. The entire assembly is enclosed in a unitary external housing with easily accessible connection fittings.

A grey water heat recovery apparatus has first and second passes in counter-flow orientation. The hot side is grey water. The cold side is fresh water. It extracts heat from the grey water. The fresh water is carried in tubing bundles in series immersed in grey water sumps in cylindrical plastic, mild steel, or stainless steel pipe. Both ends of the fresh water bundle assembly extend from the same upper end pipe closure, without a pressurized line wall penetration in the walls of the pipe. There is a non-electrically conductive barrier between the fresh water and grey water flow paths. The apparatus has a leak detection circuit and co-operable bypass valves. The tube bundle is wider at the top than at the bottom. The lower manifold has grey water passages between the centering ears. The entire assembly is enclosed in a unitary external housing with easily accessible connection fittings.

A chemical reactor that combines a pressure vessel, heat exchanger, heater, and catalyst holder into a single device is disclosed. The chemical reactor described herein reduces the cost of the reactor and reduces its parasitic heat losses. The disclosed chemical reactor is suitable for use in ammonia (NH.sub.3) synthesis.

A chemical reactor that combines a pressure vessel, heat exchanger, heater, and catalyst holder into a single device is disclosed. The chemical reactor described herein reduces the cost of the reactor and reduces its parasitic heat losses. The disclosed chemical reactor is suitable for use in ammonia (NH.sub.3) synthesis.

A heat exchanger for abating compounds produced in semiconductor processes. When hot effluent flows into the heat exchanger, a coolant can be flowed to walls of a fluid heat exchanging surface within the heat exchanger. The heat exchanging surface can include a plurality of channel regions which creates a multi stage cross flow path for the hot effluent to flow down the heat exchanger. This flow path forces the hot effluent to hit the cold walls of the fluid heat exchanging surface, significantly cooling the effluent and preventing it from flowing directly into the vacuum pumps and causing heat damage. Embodiments described herein also relate to methods of forming a heat exchanger. The heat exchanger can be created by sequentially depositing layers of thermally conductive material on surfaces using 3-D printing, creating a much smaller footprint and reducing costs.

A spiral heat exchanger includes a spiral unit, a case member, and a bracket. The spiral unit includes thin metal plates. The thin metal plates are spaced away from each other and spirally wound. The thin metal plates define flow paths. A portion or all of the flow paths are provided with a coolant flowing therein. The case member is attached to a vehicle and contains the spiral unit. The bracket is fixed to the case member and holds the spiral unit. The bracket includes a holding portion and a fixed portion. The holding portion holds a first end, a second end, or both of the spiral unit in an axial direction. The fixed portion is disposed between an outer peripheral surface of the spiral unit and an inner peripheral surface of the case member. The fixed portion is fixed to the inner peripheral surface of the case member.