A counter-flow simultaneous heat and mass exchange device is operated by directing flows of two fluids into a heat and mass exchange device at initial mass flow rates where ideal changes in total enthalpy rates of the two fluids are unequal. At least one of the following state variables in the fluids is measured: temperature, pressure and concentration, which together define the thermodynamic state of the two fluid streams at the points of entry to and exit from the device. The flow rates of the fluids at the points of entry and/or exit to/from the device are measured; and the mass flow rate of at least one of the two fluids is changed such that the ideal change in total enthalpy rates of the two fluids through the device are brought closer to being equal.

A heat exchanger includes: a first heat transfer tube unit including first heat transfer tubes arranged in parallel along a first direction within a horizontal plane; and a second heat transfer tube unit including second heat transfer tubes arranged in parallel with one another along a second direction that intersects the first direction within the horizontal plane. Each of the first heat transfer tubes and the second heat transfer tubes includes: straight portions arranged in parallel in a vertical direction; and one or more curved portions that make end portions of the straight portions communicate with each other. The straight portions of the first heat transfer tube unit and the straight portions of the first heat transfer tube unit are stacked on each other alternately.

A counter-flow fin plate heat exchanger for gas-to-gas heat exchange includes several outer channel fins, an outer channel bending plate, an inner channel fin and an inner channel bending plate. The outer channel bending plate is a flat plate with two sides bending upward vertically. The inner channel bending plate is a cuboid box without a cap on the top, and the top of the inner channel bending plate is hermetically fixed with the bottom of the outer channel bending plate. The several outer channel fins are arranged in parallel inside the outer channel bending plate. The inner channel fins are arranged inside the inner channel bending plate. Ends of a side surface corresponding to two long sides of the inner channel bending plate are respectively provided with an opening, and the two openings are respectively disposed at different ends of the two side surfaces.

A heat exchanger includes at least one first flow channel for a first medium, at least one second flow channel for a second medium, and at least one bottom that can be connected to the housing. The bottom has at least one expansion element.

A thermal device according to the present disclosure includes a ceramic container, a fluid, and a sealing portion. The container includes an internal space, an opening portion connected to the internal space, and a communication path configured to connect the internal space and the opening portion. The fluid is located in the internal space. The sealing portion blocks the opening portion. The sealing portion includes a core portion and a flange connected to the core portion. The flange is bonded to the container around the opening portion. The core portion is located inside the opening portion. A portion of the core portion is in contact with the wall surface of the opening portion.

The present invention is a system and method for determining effective ground thermal properties. Accurate prediction of required loop length for geothermal heat exchange systems is critical for optimizing performance and associated cost, yet limited by lack of knowledge of the effective average thermal properties of the surrounding ground. Testing involves first charging the ground loop by circulating fluid at constant temperature and constant rate of heat input, then halting heat input and monitoring the ground loop temperatures during discharge. One aspect of the invention is to enable separate determination of effective ground thermal conductivity and volumetric heat capacity first by adopting design elements resulting in improved reproducibility, and second by evaluating thermal conductivity near the time when the quotient Q of later discharge temperature to start-of-discharge fluid temperature is almost independent of volumetric heat capacity. Evaluation discharge times are specific to both ground loop design and charging conditions.

An electric device has a housing and an active part in the housing that can be supplied with a high voltage and that generates heat when operated. The housing is filled with an insulating liquid for cooling. A cooling system for cooling the insulating liquid has at least one cooling element which is connected to the external atmosphere in a heat-conductive manner and via which the insulating liquid is conducted. Temperature fluctuations of the electric device are limited or even prevented in an inexpensive manner. The cooling system has a rising section which is connected to the housing, is provided with rising branches, and is connected to a cooling element at each rising branch. The volume of the rising section is selected on the basis of a thermal expansion coefficient of the insulating liquid such that the fill state reaches a different number of rising branches at specific temperatures.

The purpose of the present invention is to provide a heat exchanger, which is a plate-type having a plurality of plates stacked and welded together, allowing material and processing costs to be reduced by decreasing the areas on which welding material is applied during production while assuring welding quality. The present invention comprises: a heat exchange part having heating medium channels, through which heating medium flows, and combustion gas channels, through which combustion gas burned in a burner flows, adjacently disposed in alternation in the spaces between the plurality of plates; a first welding part in which the outer edges of a pair of plates forming the heating medium channel are welded together; a second welding part in which the plates forming the combustion gas channel, between the plates forming the heating medium channel, are welded to the outer edges of the plates forming the heating medium channel to form; and a guide part for guiding the welding material molten solution of the first welding part into moving to the second welding part.

A thermal retention apparatus includes a tank and a phase change thermal energy storage unit contained within the tank that, in turn, includes a phase change material and a heat exchanger assembly. The heat exchanger assembly includes a phase change material (PCM) charging circuit for charging the phase change material, and a PCM discharging circuit for discharging the phase change material. The heat exchanger assembly includes a plurality of heat exchanger modules immersed within the phase change material, and the PCM charging circuit includes a fluid flow arrangement of the heat exchanger modules that is in parallel. The PCM discharging circuit includes a fluid flow arrangement of the heat exchanger modules that is in series.

A thermal retention apparatus includes a tank and a phase change thermal energy storage unit contained within the tank that, in turn, includes a phase change material and a heat exchanger assembly. The heat exchanger assembly includes a phase change material (PCM) charging circuit for charging the phase change material, and a PCM discharging circuit for discharging the phase change material. The heat exchanger assembly includes a plurality of heat exchanger modules immersed within the phase change material, and the PCM charging circuit includes a fluid flow arrangement of the heat exchanger modules that is in parallel. The PCM discharging circuit includes a fluid flow arrangement of the heat exchanger modules that is in series.