Abstract: Thermal management techniques include: transporting a refrigerant fluid from a receiver to an inlet of a flash tank that has a vapor-side outlet and liquid-side outlet such that a liquid phase of the refrigerant fluid moves to a bottom of the flash tank and outputs from the liquid-side outlet; forming a solid-vapor state from the liquid phase by expanding the liquid phase with an expansion valve to a first pressure that is less than a triple point pressure to form a solid-vapor mixture of the refrigerant fluid; extracting heat from a heat load with an evaporator that receives the solid-vapor mixture of the refrigerant fluid and sublimates the solid state of the solid-vapor mixture of the refrigerant fluid directly into a vapor phase of the refrigerant fluid; and discharging, from an exhaust line, the vapor phase to an ambient environment without returning the vapor phase to the receiver.

Abstract: A thermal management system includes an open-circuit refrigeration system including a cooling system configured to supply a cooling medium. The open-circuit refrigeration system includes a receiver having a receiver outlet, the receiver configurable to store a refrigerant fluid, the receiver configured to receive the cooling medium from the cooling system, an evaporator coupled to the receiver outlet, the evaporator configurable to receive liquid refrigerant fluid from the receiver outlet and to extract heat from a heat load when the heat load contacts or is proximate to the evaporator a control device configurable to control a temperature of the heat load and an exhaust line, with the receiver, the evaporator, and the exhaust line coupled to form an open-circuit refrigerant fluid flow path.

Abstract: Thermal management systems include an open circuit refrigeration system featuring a receiver configurable to store a refrigerant fluid, an evaporator configurable to extract heat from a heat load when the heat load contacts the evaporator, and an exhaust line, where the receiver, the evaporator, and the exhaust line are connected to form a refrigerant fluid flow path, and a first control device configurable to control a vapor quality of the refrigerant fluid at an outlet of the evaporator along the refrigerant fluid flow path.

Abstract: A thermal management system that includes an open-circuit refrigeration system having an open-circuit refrigerant fluid flow path is described. The open-circuit refrigeration system includes a receiver configured to store a refrigerant fluid, an evaporator configured to receive the refrigerant fluid at a evaporator inlet and to extract heat from a heat load that contacts the evaporator, and provide refrigerant vapor at a evaporator outlet. The open-circuit refrigeration system also includes a vapor pump device having a vapor pump inlet that receives the refrigerant vapor and having a vapor pump outlet that outputs compressed refrigerant vapor to an exhaust line coupled to the vapor pump outlet, with the receiver, the evaporator, the vapor pump device, and the exhaust line connected in the open-circuit refrigerant fluid flow path.

Abstract: A thermal management system includes an open-circuit refrigeration system having an open-circuit refrigerant fluid flow path. The open-circuit refrigeration system includes a receiver configured to store a refrigerant fluid, an evaporator configured to receive the refrigerant fluid at an evaporator inlet and to extract heat from a heat load that contacts the evaporator, and provide refrigerant vapor at an evaporator outlet. The open-circuit refrigeration system also includes a vapor pump device having a vapor pump inlet that receives the refrigerant vapor and having a vapor pump outlet that outputs compressed refrigerant vapor to an exhaust line coupled to the vapor pump outlet, with the receiver, the evaporator, the vapor pump device, and the exhaust line connected in the open-circuit refrigerant fluid flow path.

Abstract: A thermal management system includes a refrigerant receiver configured to store a refrigerant fluid, a closed-circuit refrigeration system having a closed-circuit fluid path with the refrigerant receiver, and with the closed-circuit refrigeration system configured to receive refrigerant from the refrigerant receiver through the closed-circuit fluid path, an open-circuit refrigeration system having an open-circuit fluid path, and with the refrigerant receiver disposed in the open-circuit fluid path, with the open-circuit refrigeration system configured to receive refrigerant through the open-circuit fluid path, and discharge refrigerant fluid through an exhaust line, and an evaporator arrangement configured to receive the refrigerant and to extract heat from at least one heat load, the evaporator arrangement having an inlet and an outlet, with the evaporator disposed in a common portion of the closed-circuit fluid path and the open-circuit fluid path.

Abstract: A thermal management system includes a closed-circuit refrigeration system that includes a vapor cycle system (VCS) and a liquid pumping system (LPS). The VCS includes a receiver that stores a refrigerant fluid and a liquid separator. The vapor cycle system is configured to operate in one or more operational modes including at least one of a TES cooling mode, a heat load cooling mode, or a pump-down mode. The LPS includes a thermal energy storage (TES) that stores a phase change material (PCM) and a pump fluidly coupled to at least one evaporator. The evaporator is configured to extract heat from a heat load that is in thermal conductive or convective contact to the evaporator to transfer heat to the refrigerant fluid and provide the refrigerant fluid from an evaporator outlet to the TES.

Abstract: A thermal management system that includes an open-circuit refrigeration system having an open-circuit refrigerant fluid flow path is described. The open-circuit refrigeration system includes a receiver configured to store a refrigerant fluid, an evaporator configured to receive the refrigerant fluid at a evaporator inlet and to extract heat from a heat load that contacts the evaporator, and provide refrigerant vapor at a evaporator outlet. The open-circuit refrigeration system also includes a vapor pump device having a vapor pump inlet that receives the refrigerant vapor and having a vapor pump outlet that outputs compressed refrigerant vapor to an exhaust line coupled to the vapor pump outlet, with the receiver, the evaporator, the vapor pump device, and the exhaust line connected in the open-circuit refrigerant fluid flow path.

Abstract: Disclosed is a mechanism to exhaust refrigerant vapor resulting from operation of a thermal management system that is used to cool a thermal load by a vehicle, such as an airborne vehicle. The thermal management system includes an open circuit refrigeration system featuring a receiver configured to store a liquid refrigerant fluid, an evaporator configured to extract heat from the thermal load that contacts the evaporator, and an exhaust line, where the receiver, the evaporator, and the exhaust line are connected to provide an open refrigerant fluid flow path. Other implementations of open circuit refrigeration systems include the use of a gas receiver, a pump and an ejector are also described, as are other mechanisms to exhaust refrigerant vapor resulting from operation of the thermal management system.

Abstract: A thermal management system includes an integrated open-circuit refrigeration system and closed-circuit heat pump system. The thermal management system includes a receiver having a first receiver port and a second receiver port, the receiver configured to store a refrigerant fluid, an evaporator having a first evaporator port and a second evaporator port, the heat pump circuit having a closed-circuit fluid path with the receiver and the evaporator and an open-circuit refrigeration system configured to receive refrigerant from the receiver, with the open-circuit refrigeration system having an open-circuit fluid path that includes the receiver and the evaporator.

Abstract: A thermal management system includes an integrated open-circuit refrigeration system and closed-circuit heat pump system. The thermal management system includes a receiver having a first receiver port and a second receiver port, the receiver configured to store a refrigerant fluid, an evaporator having a first evaporator port and a second evaporator port, the heat pump circuit having a closed-circuit fluid path with the receiver and the evaporator and an open-circuit refrigeration system configured to receive refrigerant from the receiver, with the open-circuit refrigeration system having an open-circuit fluid path that includes the receiver and the evaporator.

Abstract: A thermal management system is described. The thermal management system includes a receiver configured to store a refrigerant, the receiver having a receiver inlet and a receiver outlet, a closed-circuit refrigeration system including a vapor compression closed-circuit system that includes the receiver, and a closed-circuit system that includes the receiver, wherein the closed-circuit refrigeration system is configurable to receive refrigerant from the receiver through one or both of the vapor compression closed-circuit system and the closed-circuit system.

Abstract: A thermal management system that includes an open-circuit refrigeration system having an open-circuit refrigerant fluid flow path is described. The open-circuit refrigeration system includes a receiver configured to store a refrigerant fluid, an evaporator configured to receive the refrigerant fluid at a evaporator inlet and to extract heat from a heat load that contacts the evaporator, and provide refrigerant vapor at a evaporator outlet. The open-circuit refrigeration system also includes a vapor pump device having a vapor pump inlet that receives the refrigerant vapor and having a vapor pump outlet that outputs compressed refrigerant vapor to an exhaust line coupled to the vapor pump outlet, with the receiver, the evaporator, the vapor pump device, and the exhaust line connected in the open-circuit refrigerant fluid flow path.

Abstract: A thermal management system includes a closed-circuit refrigeration system (CCRS) that includes a vapor cycle system (VCS). The VCS includes a receiver configured to store a refrigerant fluid; a liquid separator; a compressor; a condenser; at least one evaporator configured to extract heat from at least one heat load that is in thermal conductive or convective contact with the evaporator; and a thermal energy storage (TES) that stores a phase change material. The thermal management system further includes a liquid pumping system (LPS) that includes the TES, the at least one evaporator, and the liquid separator, with the LPS further including a pump. The VCS is configured to operate one at a time in at least one of three operational modes that are a TES cooling mode, a heat load cooling mode, or a pump-down mode. The LPS is configured to operate in the heat load cooling mode.

Abstract: A thermal management system includes a receiver configured to store a refrigerant fluid; a refrigeration system having a refrigerant fluid path that includes the receiver, and at least one evaporator disposed in the refrigerant fluid path. The refrigeration system is configured to receive the refrigerant fluid from the receiver through the refrigerant fluid path. The at least one evaporator is configured to receive the refrigerant fluid and to extract heat from at least one heat load having a specified thermal inertia that is in at least one of thermal conductive or convective contact with the at least one evaporator.

Abstract: A thermal management system includes an open-circuit refrigeration system including a cooling system configured to supply a cooling medium. The open-circuit refrigeration system includes a receiver having a receiver outlet, the receiver configurable to store a refrigerant fluid, the receiver configured to receive the cooling medium from the cooling system, an evaporator coupled to the receiver outlet, the evaporator configurable to receive liquid refrigerant fluid from the receiver outlet and to extract heat from a heat load when the heat load contacts or is proximate to the evaporator a control device configurable to control a temperature of the heat load and an exhaust line, with the receiver, the evaporator, and the exhaust line coupled to form an open-circuit refrigerant fluid flow path.

Abstract: Thermal management systems are described. These systems include a refrigerant receiver configured to store a refrigerant fluid, an evaporator, a closed-circuit refrigeration system having a closed fluid circuit path, with the refrigerant receiver and evaporator disposed in the closed fluid circuit path, and the closed fluid circuit path including a condenser and compressor. These systems also include a modulation capacity control circuit configured to selectively divert refrigerant vapor flow to the condenser from the compressor by diverting a portion of refrigerant vapor flow (diverted flow) from the compressor to the refrigerant receiver in accordance with cooling capacity demand.

Abstract: Thermal management systems are described. These systems include a refrigerant receiver configured to store a refrigerant fluid, an evaporator, a closed-circuit refrigeration system having a closed fluid circuit path, with the refrigerant receiver and evaporator disposed in the closed fluid circuit path, and the closed fluid circuit path including a condenser and compressor. These systems also include a modulation capacity control circuit configured to selectively divert refrigerant vapor flow to the condenser from the compressor by diverting a portion of refrigerant vapor flow (diverted flow) from the compressor to the refrigerant receiver in accordance with cooling capacity demand.

Abstract: A thermal management system includes a refrigerant receiver configured to store a refrigerant fluid, an evaporator arrangement that removes heat from a heat load converting a portion of the refrigerant fluid to refrigerant vapor and a liquid separator having an inlet, a liquid side outlet, and a vapor side outlet. The system also includes a pump that pumps refrigerant liquid received from the liquid side outlet of the liquid separator and a closed-circuit refrigeration system having a closed-circuit fluid path that includes the refrigerant receiver, the liquid separator, the pump, and the evaporator arrangement, the closed-circuit refrigeration system further including a compressor and a condenser.

Abstract: Thermal management techniques include: transporting a refrigerant fluid from a receiver to an inlet of a flash tank that has a vapor-side outlet and liquid-side outlet such that a liquid phase of the refrigerant fluid moves to a bottom of the flash tank and outputs from the liquid-side outlet; forming a solid-vapor state from the liquid phase by expanding the liquid phase with an expansion valve to a first pressure that is less than a triple point pressure to form a solid-vapor mixture of the refrigerant fluid; extracting heat from a heat load with an evaporator that receives the solid-vapor mixture of the refrigerant fluid and sublimates the solid state of the solid-vapor mixture of the refrigerant fluid directly into a vapor phase of the refrigerant fluid; and discharging, from an exhaust line, the vapor phase to an ambient environment without returning the vapor phase to the receiver.