A heat exchanger is provided including a first header and a second header and a plurality of heat exchange tube arranged in spaced parallel relationship and fluidly coupling the first and second header. A flow restricting element defining a first volume and a second volume is positioned within one of the first and second header. The heat exchanger has a multi-pass configuration such that a first portion of the plurality of heat exchange tubes are coupled to the first volume and form a first fluid pass of the heat exchanger and a second portion of the plurality of heat exchange tubes are coupled to the second volume and form a second fluid pass of the heat exchanger. During operation, the heat transfer fluid conveyed through the first volume has a first saturation temperature and the heat transfer fluid conveyed through the second volume has a different second saturation temperature.

A gas turbine engine includes a turbomachine and a thermal management system. The thermal management system includes a heat source heat exchanger configured to collect heat from the turbomachine during operation; a heat sink heat exchanger; and a thermal transport bus having a heat exchange fluid configured to flow therethrough at a pressure within an operational pressure range. The thermal management system defines an operational temperature range for the heat exchange fluid, the operational temperature range having a lower temperature limit less than about zero degrees Fahrenheit at a pressure within the operational pressure range and an upper temperature limit of at least about 1000 degrees Fahrenheit at a pressure within the operational pressure range.

A method of controlling an HVACR unit in an HVACR system including an HVACR unit through which a process fluid is pumped to meet a temperature control demand includes monitoring, by a controller, a flowrate of the process fluid through the HVACR unit. When the flowrate of the process fluid is above a minimum flowrate threshold, the process fluid is provided to one or more terminals in the HVACR system according to the temperature control demand. A bypass flow of the process fluid through a bypass line is disabled by changing a state of a valve fluidly connected to the bypass line and one of the one or more terminals to a flow disabled state. When the flowrate of the process fluid is below the minimum flowrate threshold, the controller enables the bypass flow of the process fluid through the bypass line.

Methods and valves for providing a continuous flow of cooler fluid in a fluid circuit of a thermal control system between a cooler and automotive transmission such that free flow of cooler fluid between the cooler and transmission exists at vehicle start-up. Fluid flow to and from the cooler is bypassed in case of pressure increases in cooler lines or pressure differentials, for example cause by a blockage in the cooler, such that the cooler fluid flow bypasses the cooler and continues in the fluid circuit through a thermal element of the thermal control system and back to the transmission.

A battery thermal management system for an air vehicle includes a first heat exchange circuit, a battery in thermal communication with the first heat exchange circuit, and a heat exchanger positioned on the first heat exchange circuit. The heat exchanger is operatively connected to a second heat exchange circuit. The system includes a controller operatively connected to the second heat exchange circuit. The controller is configured to variably select whether heat will be rejected to the second heat exchange circuit. A method for controlling a thermal management system for an air vehicle includes determining an expected fluid temperature of fluid in a fluid heat exchange circuit. The method includes commanding a flow restrictor at least partially closed or commanding the flow restrictor at least partially open.

A heat exchanger is provided with a unitary, single-piece structure that can be formed via 3D printing, for example. The heat exchanger includes a main body a plurality of plates stacked and integrally formed with the body. First fluid channels are defined by gaps in the material of the main body, and second fluid channels are defined by gaps in the material of the main body and are stacked with the first fluid channels in alternating fashion, separated by the plates. Each of the first fluid channels define a first flow path, and each of the second fluid channels define a second flow path. A portion of the first flow paths overlap, and are oriented opposite to, a portion of the second flow paths. Another portion of the first flow paths overlap, and are oriented transverse to, another portion of the second flow paths.

A turbine engine heat exchanger for exchanging heat between a first fluid and a second fluid includes a reference axis, a network of tubular meshes having a plurality of meshes each of which is formed, successively in a reference direction, of at least two curvilinear branches, called anterior branches, of a junction where the two anterior branches meet, and of at least two curvilinear branches, called posterior branches, diverging from the junction, wherein the first and second fluid have a respective general direction of flow, and the general direction of flow of the first fluid is parallel to the general direction of flow of the second fluid. The present disclosure also concerns a turbine engine comprising the heat exchanger and a manufacturing method for manufacturing the heat exchanger.

A turbine engine heat exchanger for exchanging heat between a first fluid and a second fluid includes a reference axis, a network of tubular meshes having a plurality of meshes each of which is formed, successively in a reference direction, of at least two curvilinear branches, called anterior branches, of a junction where the two anterior branches meet, and of at least two curvilinear branches, called posterior branches, diverging from the junction, wherein the body of the heat exchanger is of cylindrical shape. The present disclosure also concerns a turbine engine comprising the heat exchanger and a manufacturing method for manufacturing the heat exchanger.

A gas turbine engine includes a turbomachine and a thermal management system. The thermal management system includes a heat source heat exchanger configured to collect heat from the turbomachine during operation; a heat sink heat exchanger; and a thermal transport bus having a heat exchange fluid configured to flow therethrough at a pressure within an operational pressure range. The thermal management system defines an operational temperature range for the heat exchange fluid, the operational temperature range having a lower temperature limit less than about zero degrees Fahrenheit at a pressure within the operational pressure range and an upper temperature limit of at least about 1000 degrees Fahrenheit at a pressure within the operational pressure range.

The invention relates to a heat exchanger comprising a support wall and a first plurality of fins that each stand proud from an outer surface of the support wall and are designed to have a first air flow pass over them. According to the invention, the heat exchanger comprises, downstream of the first plurality of fins, a second plurality of fins that each stand proud from the outer surface of the support wall, the first and second pluralities of fins being separated by distribution means which are configured in such a way that the first air flow flows outside the second plurality of fins and a second air flow flowing outside the first plurality of fins passes through the second plurality of fins.