Abstract: The disclosure relates to plate-fin and manifold assemblies for heat exchangers. In some examples, an assembly includes a first plate and a second plate. The assembly also includes a plurality of fins disposed between the first plate and the second plate. In addition, the plurality of fins are spaced apart by a width large enough adapted for counter-flow of a plurality of fluids between adjacent fins of the plurality of fins. Further, the plurality of fins are configured to direct fluid flow across a length of the first plate and the second plate.

Abstract: The disclosure relates to heat-mass exchangers. In some examples, a heat-mass exchanger includes a housing configured to receive a flow of supply air cooled and dehumidified by a liquid desiccant conditioner system. The heat-mass exchanger also includes a header configured to receive low concentration liquid desiccant from the liquid desiccant conditioner system, and feed the low concentration liquid desiccant onto one or more heat transfer tubes within the housing. The one or more heat transfer tubes are configured to dissipate heat to the liquid desiccant to generate relatively higher concentration desiccant. Further, the heat-mass exchanger includes a collector that is configured to capture the higher concentration desiccant, and feed the higher concentration desiccant to the liquid desiccant conditioner system.

Abstract: The disclosure relates to plate-fin and manifold assemblies for heat exchangers. In some examples, an assembly includes a first plate and a second plate. The assembly also includes a plurality of fins disposed between the first plate and the second plate. In addition, the plurality of fins are spaced apart by a width large enough adapted for counter-flow of a plurality of fluids between adjacent fins of the plurality of fins. Further, the plurality of fins are configured to direct fluid flow across a length of the first plate and the second plate.

Abstract: The disclosure relates to mass transfer assemblies for heating ventilation and cooling systems.

Abstract: A moisture swing system including a moisture swing housing including a moisture swing material and a liquid desiccant (LD) regenerator is provided. The LD regenerator is adapted to contact a low concentration liquid desiccant (LCLD) stream with a dry CO2 feed stream, where moisture from the LCLD stream is transferred into the CO2 feed stream as water vapor to form a high concentration liquid desiccant (HCLD) stream and a wet CO2 feed stream. The wet CO2 stream is contacted with the moisture swing material to form a wet, concentrated CO2 stream that exits the moisture swing housing. The system can also include a LD conditioner adapted to produce a dry CO2-rich target stream to contact with the moisture swing material. The LD conditioner and the LD regenerator can be connected to produce a closed-loop system that uses and regenerates the LD used in the moisture swing system.

Abstract: The disclosure relates to heating ventilation and cooling systems that use liquid desiccant to remove moisture from air. In some examples, a system is configured to measure the density of a liquid. The system includes a measuring column having an inlet and an outlet. The inlet is a predetermined distance below the outlet, and the outlet is adapted such that liquid exits the outlet to low pressure. The system also includes a pressure sensor located proximate the inlet. Further, the system includes a processor adapted for receiving a reading from the pressure sensor and calculating a density of liquid flowing through the system using the reading.

Abstract: The disclosure relates to chiller systems and, more particularly, to chiller systems that employ electrically driven desiccant regenerators. In some examples, a chiller system includes a heat and mass exchanger and an electrically driven desiccant regenerator in fluid communication with the heat and mass exchanger. The heat and mass exchanger is configured to dehumidify a flow of air, and provide the dehumidified flow of air to a cooling tower. Further, the electrically driven desiccant regenerator is configured to provide concentrated liquid desiccant to the heat and mass exchanger for dehumidifying the flow of air.

Abstract: The disclosure relates to heat and mass exchangers. In some examples, a heat-mass exchanger includes a plurality of regeneration fins extending generally vertically, and a plurality of desiccant feed tubes extending generally horizontally. The heat-mass exchanger also includes a plurality of regenerator heating tubes extending generally horizontally. The plurality of desiccant feed tubes are positioned above the plurality of regenerator heating tubes. In addition, the plurality of desiccant feed tubes and the plurality of regenerator heating tubes extend through the plurality of regeneration fins. Further, the plurality of desiccant feed tubes include feed tube openings adapted for delivering liquid desiccant onto surfaces of the plurality of regeneration fins.

Abstract: The disclosure relates to machine learning and artificial intelligence based control systems for heating ventilation and cooling systems. In some examples, a computing device receives flow data characterizing flow rates of a first fluid over a time range. The computing device also receives humidity data characterizing humidity levels over the time range. Further, the computing device receives temperature data characterizing temperatures over the time range. The computing device also generates a training set of features based on the flow data, the humidity data, and the temperature data. The computing device further trains a machine learning process based on the training set of features. The computing device stores machine learning model data characterizing the trained machine learning process in a data repository.

Abstract: The disclosure relates to parallel plate and manifold assemblies for heat exchangers. In some examples, a plate assembly includes at least one plate. The plate includes a first side defining a side of a conditioning channel, where the first side is configured to receive desiccant. The plate also includes a second side that is opposite the first side. The second side defines a side of an exhaust channel. In addition, at least one of the first side and the second side include a plurality of support structures that are distributed in a predetermined pattern and are configured to maintain a predetermined width of the respective conditioning channel or exhaust channel.

Abstract: The disclosure relates to mass transfer assemblies for heating ventilation and cooling systems. In some examples, a mass transfer apparatus includes a stack of plates, where the stack defines channel pairs, and each channel pair has one conditioning channel and one exhaust channel. An upstream edge of the conditioning channels and a downstream edge of the exhaust channels define an upstream portion of the stack and extend laterally. In addition, the mass transfer apparatus is adapted to feed a fluid feed stream to the conditioning channels, and feed a first portion of the conditioned fluid feed stream to the exhaust channels. For each channel pair, an open portion of the upstream edge of the conditioning channel is open for receiving the fluid feed stream, and an open portion of the downstream edge of the exhaust channel is open for exhausting the conditioned fluid feed stream.

Abstract: The disclosure relates to mass transfer assemblies for heating ventilation and cooling systems. In some examples, a mass transfer apparatus includes a stack of plates defining alternating conditioning channels and exhaust channels. The mass transfer apparatus also includes a fluid distribution system that includes a conditioning supply line defined in part by a first hole in an upper portion of each of the plates, and a working supply line defined in part by a second hole in the upper portion of each of the plates. The conditioning supply line supplies a conditioning fluid to the conditioning channels and the working supply line supplies a working fluid to the exhaust channels. The fluid distribution system also includes a conditioning return line that collects the conditioning fluid, and a working return line that collects the working fluid, each collection at a lower portion of each of the plates.

Abstract: The disclosure relates to fin inserts for heat and mass exchangers and corresponding methods. For instance, in some examples, a fin insert to a heat and mass exchanger includes a generally rigid, longitudinally-extending member that includes a top portion and side portions. The side portions may be disposed on opposite sides of the top portion, and may include a concave shape facing away from one another. The side portions may further are each be positioned around a portion of a respective heat transfer tube.

Abstract: The disclosure relates to plate-fin and manifold assemblies for heat exchangers. In some examples, an assembly includes a first plate and a second plate. The assembly also includes a plurality of fins disposed between the first plate and the second plate. In addition, the plurality of fins are spaced apart by a width large enough adapted for counter-flow of a plurality of fluids between adjacent fins of the plurality of fins. Further, the plurality of fins are configured to direct fluid flow across a length of the first plate and the second plate.

Abstract: The disclosure relates to fin inserts for heat and mass exchangers and corresponding methods. For instance, in some examples, a fin insert to a heat and mass exchanger includes a generally rigid, longitudinally-extending member that includes a top portion and side portions. The side portions may be disposed on opposite sides of the top portion, and may include a concave shape facing away from one another. The side portions may further are each be positioned around a portion of a respective heat transfer tube.

Abstract: A liquid desiccant regeneration system and method of liquid desiccant regeneration are described. The liquid desiccant regeneration system includes a liquid desiccant regenerator having an engine producing a heated exit stream, and at least one dehydrating tube comprising a first water vapor permeable wall. A low concentration liquid desiccant stream feeds into the liquid desiccant regenerator, while a high concentration liquid desiccant stream exiting the liquid desiccant regenerator. A carrier stream and the low concentration liquid desiccant are in contact with opposite sides of the first water vapor permeable wall, and the low concentration liquid desiccant stream is heated by heat from the heated exit stream to drive water from the low concentration liquid desiccant stream through the first water vapor permeable wall to the carrier stream to form a humidified carrier stream.

Abstract: A liquid desiccant regeneration system and method of liquid desiccant regeneration are described. The liquid desiccant regeneration system includes a liquid desiccant regenerator having an engine producing a heated exit stream, and at least one dehydrating tube comprising a first water vapor permeable wall. A low concentration liquid desiccant stream feeds into the liquid desiccant regenerator, while a high concentration liquid desiccant stream exiting the liquid desiccant regenerator. A carrier stream and the low concentration liquid desiccant are in contact with opposite sides of the first water vapor permeable wall, and the low concentration liquid desiccant stream is heated by heat from the heated exit stream to drive water from the low concentration liquid desiccant stream through the first water vapor permeable wall to the carrier stream to form a humidified carrier stream.

Abstract: A heat and mass exchanger system is described. The heat and mass exchange system can include a plurality of exchange components extending across a heat and mass exchanger (HMX) duct, where a flow through the HMX duct is cross-flow relative to said exchange components. The exchange components can include a plurality of first elongated, hollow conduits and a plurality of second elongated, hollow conduit, where either the first elongated, hollow conduits or the second elongated, hollow conduits have water vapor permeable exterior walls, and a carrier air stream and a liquid desiccant stream flow in contact with opposite sides of the water vapor permeable exterior walls.

Abstract: A liquid desiccant regeneration system and method of liquid desiccant regeneration are described. The liquid desiccant regeneration system includes a liquid desiccant regenerator having an engine producing a heated exit stream, and at least one dehydrating tube comprising a first water vapor permeable wall. A low concentration liquid desiccant stream feeds into the liquid desiccant regenerator, while a high concentration liquid desiccant stream exiting the liquid desiccant regenerator. A carrier stream and the low concentration liquid desiccant are in contact with opposite sides of the first water vapor permeable wall, and the low concentration liquid desiccant stream is heated by heat from the heated exit stream to drive water from the low concentration liquid desiccant stream through the first water vapor permeable wall to the carrier stream to form a humidified carrier stream.

Abstract: A composite flow field element, such as a separator plate used in a high temperature air-cooled fuel cell assembly, preferably includes a metal sheet substrate of non-uniform thickness, such as a mesh, and flexible graphite layers bonded to the metal mesh substrate by an electrically conductive bonding agent.