Abstract: A two-phase pump loop (TPPL) for dissipating a thermal load during operation of an apparatus includes a coolant, a vapor/liquid receiver, a pump, an evaporator, a condenser, a valve (V1) configured to regulate a pressure at an outlet of the condenser; a valve (V2) having a control set point set equivalent to a low pressure (PL) measured in the vapor/liquid receiver; and a controller configured to control the set points of V1 and V2. The TPPL is configured to cool the thermal load with tight control of the temperature of the coolant that is cooling the apparatus. The TPPL may be combined with a vapor cycle system (VCS) to provide a thermal management system with the VCS being configured to use the same or different coolant than the TPPL.

Abstract: A thermal management system for regulating dissipation of multiple thermal loads during operation of an apparatus includes a two-phase pump loop (TPPL), a vapor cycle system (VCS), and a liquid thermal energy storage (TES) system integrated together to maintain the apparatus at a constant temperature. The TPPL is configured to remove heat from the apparatus; the TES system is configured to provide thermal energy storage and temperature regulation; and the VCS is configured to transfer heat to the environment. The multiple thermal loads include a primary thermal load in the form of heat from the apparatus and a secondary thermal load in the form of at least one of a housekeeping thermal load or a power electronics thermal load. The primary and secondary loads are at different temperatures with each being independently selected to be transient or steady state.

Abstract: A two-phase pump loop (TPPL) for dissipating a thermal load during operation of an apparatus includes a coolant, a vapor/liquid receiver, a pump, an evaporator, a condenser, a valve (V1) configured to regulate a pressure at an outlet of the condenser; a valve (V2) having a control set point set equivalent to a low pressure (PL) measured in the vapor/liquid receiver; and a controller configured to control the set points of V1 and V2. The TPPL is configured to cool the thermal load with tight control of the temperature of the coolant that is cooling the apparatus. The TPPL may be combined with a vapor cycle system (VCS) to provide a thermal management system with the VCS being configured to use the same or different coolant than the TPPL.

Abstract: A thermal management system for regulating dissipation of multiple thermal loads during operation of an apparatus includes a two-phase pump loop (TPPL), a vapor cycle system (VCS), and a liquid thermal energy storage (TES) system integrated together to maintain the apparatus at a constant temperature. The TPPL is configured to remove heat from the apparatus; the TES system is configured to provide thermal energy storage and temperature regulation; and the VCS is configured to transfer heat to the environment. The multiple thermal loads include a primary thermal load in the form of heat from the apparatus and a secondary thermal load in the form of at least one of a housekeeping thermal load or a power electronics thermal load. The primary and secondary loads are at different temperatures with each being independently selected to be transient or steady state.

Abstract: A salinity measuring apparatus utilizes a specialized probe with dual electrode pairs, one of the pairs being used to pass current through the electrolyte, while the other picks up voltage drop across a region in the electrolyte and feeds it back to the current producing amplifier, which adjusts the current output until a stabilized, predetermined voltage difference occurs across the voltage electrodes. The circuit which drives the current between the current electrodes produces a positive pulse, and an ensuing negative pulse, which are sequentially applied across the electrodes so that two separate measurements are made using pulses of opposite polarity to cancel out electrode polarizations. An amplifier circuit receives a pulse from the voltage source and applies it to the electrodes.