Abstract: A room 100 in a building has a living etc. space 101 of volume V that is an enclosed space. Ventilation of an air flow F is performed from the outside to the living etc. space 101. Entering/exiting of air as an air current between the inside of the living etc. space 101 and the outside is eliminated, and at least a part of the boundary between the living etc. space 101 and the outside is configured from a gas exchange membrane 310 having a diffusion constant D, a thickness L, and an area A for gas molecules of interest. When air inside the living etc. space 101 is sufficiently agitated and the concentration of gas molecules constituting the air is made spatially uniform, ?(t) is controlled so as to vary according to ? ? ( t ) = ? o - BL AD ? ( 1 - exp ? ( - [ AD ? / ? L ] ? t ? / ? V ) ) ( 9 ) B(m3/s) is the gas consumption amount inside the living etc. space 101, ?1 (t) is the gas concentration inside the living etc.

Abstract: An object is to provide a refrigeration cycle apparatus capable of reducing freezing in a lower part of a heat exchanger in which drainage water tends to accumulate and reducing an amount of refrigerant in a refrigerant circuit. The refrigeration cycle apparatus includes the refrigerant circuit 1 connecting, by refrigerant pipes, a compressor, a first expansion device, and a first heat exchanger configured to serve as evaporator during heating operation. The first heat exchanger is provided with a first heat exchange unit and a second heat exchange unit connected to the first heat exchange unit in series in the refrigerant circuit. The first expansion device is connected in parallel with the second heat exchange unit in the refrigerant circuit, and the second heat exchange unit is placed at a position lower than a position of the first heat exchange unit.

Abstract: Provided is a heat exchanger, including: a refrigerant distributor including: a gas-liquid separating portion having a function of separating a gas-liquid refrigerant mixture into a liquid refrigerant and a gas refrigerant; and a distributing portion provided to the gas-liquid separating portion. A plurality of heat transfer pipes connected to the distributing portion. The plurality of heat transfer pipes are arranged side by side in a first direction, and extend along a second direction intersecting with the first direction. When the refrigerant distributor is viewed along a direction orthogonal to each of the first direction and the second direction, a first space forming portion overlaps a region of the plurality of heat transfer pipes. When the refrigerant distributor and the heat transfer pipes are viewed along the first direction, a clearance is present between the gas-liquid separating portion and the heat transfer pipes.

Abstract: In a heat exchanger, each of a plurality of heat exchange members includes: a main body portion including a heat transfer pipe; and extending portions provided to the main body. The extending portions extend from ends of the main body portion in a third direction. When a dimension of the main body portion in the third direction is represented by La, a dimension of the extending portions in the third direction is represented by Lf, a dimension of a wall thickness of each of the heat transfer pipes is represented by tp, and a thickness dimension of each of the extending portions is represented by Tf, relationships: Lf/La?1 and Tf?tp are satisfied.

Abstract: An auxiliary heat exchange unit of a heat exchanger has a first auxiliary heat exchange region and a second auxiliary heat exchange region. A main heat exchange unit has a first main heat exchange region, a second main heat exchange region, a third main heat exchange region, and a fourth main heat exchange region. The auxiliary heat exchange unit and the main heat exchange unit are configured to cause refrigerant to flow successively through the first auxiliary heat exchange region, the second auxiliary heat exchange region, the first main heat exchange region, the second main heat exchange region, the fourth main heat exchange region, and the third main heat exchange region when the heat exchanger functions as an evaporator.

Abstract: An object is to provide a heat exchanger, a heat exchanger unit, and a refrigeration cycle apparatus in which frost melt water is inhibited from reaching an upper surface of a header and the heat exchange performance and the reliability are improved. The invention includes: a plurality of heat transfer tubes arranged in parallel with each other; a fin connected to at least one of the plurality of heat transfer tubes; and a header having a header end surface being a surface along a direction in which the plurality of heat transfer tubes are arranged in parallel with each other, the header being connected to one end portions of the plurality of heat transfer tubes.

Abstract: An outdoor heat exchanger of an outdoor unit includes a main heat exchanger portion and an auxiliary heat exchanger portion. In the main heat exchanger portion, refrigerant path groups are formed. In the auxiliary heat exchanger portion, refrigerant paths are formed. The refrigerant path in the auxiliary heat exchanger portion, which is located closest to the main heat exchanger portion, is connected to the refrigerant path group in the main heat exchanger portion, which is disposed in a region where a wind velocity of the outdoor air passing through the main heat exchanger portion is relatively high. In addition, the refrigerant path is connected to the refrigerant path group. The refrigerant path is connected to the refrigerant path group. The refrigerant path is connected to the refrigerant path group.

Abstract: An outdoor heat exchanger includes: a main heat exchange area; a sub heat exchange area; and a connecting pipe and a connecting pipe interconnecting the main heat exchange area and the sub heat exchange area. The main heat exchange area has a main heat exchange channel and a main heat exchange channel. The sub heat exchange area has a sub heat exchange channel, a sub heat exchange channel, and a sub heat exchange channel. The connecting pipe connects the sub heat exchange channel and the sub heat exchange channel to the main heat exchange channel while the sub heat exchange channels are joined together. The connecting pipe interconnects the sub heat exchange channel and the main heat exchange channel.

Abstract: A refrigeration cycle apparatus includes a refrigerant circuit including a compressor, a condenser, a pressure reducing device, and an evaporator connected by a refrigerant pipe. A refrigerant including a refrigerant having flammability is used as refrigerant circulating in the refrigerant circuit. The evaporator and the pressure reducing device are accommodated in a unit. The evaporator is disposed in the unit in such a manner that a linear distance between a refrigerant inlet of the evaporator and a refrigerant outlet of the pressure reducing device is shorter than a linear distance between a refrigerant outlet of the evaporator and the refrigerant outlet of the pressure reducing device.

Abstract: A refrigeration cycle apparatus includes a refrigerant circuit and a controller for controlling the refrigerant circuit. The refrigerant circuit includes a compressor, a condenser, a pressure-reducing device and an evaporator. Refrigerant circulating through the refrigerant circuit contains propane or propylene. The controller sets a degree of superheat of refrigerant at an entrance port of the compressor to be a value greater than or equal to 10 degrees.

Abstract: Provided are a system of highly clean rooms capable of continuously maintaining high cleanliness of air of class 1 or above and supplying enough oxygen inside the room for several persons to live in and a wall adapted to the structure of such a system. The system of highly clean rooms 10 is provided with a living space 6 and a space 5 between the roof and the ceiling as subspaces of an enclosed space formed by a room 1a. One of the lateral walls of the room 1a is constituted of a wall 9 with an internal space 7, which is a hollow wall. The internal space 7 and the living space 6 are in contact via an inner wall 9a of the wall 9, and a gas exchange membrane 26 is stretched in the inner wall 9a.

Abstract: A heat exchanger includes: a plate-like fin having one end and an other end in a first direction; and a first heat transfer tube and a second heat transfer tube that each extends through the fin and that are adjacent to each other in a second direction. A portion to which the fin and the first heat transfer tube are connected and a clearance portion that separates between the fin and the first heat transfer tube are disposed between the fin and the first heat transfer tube. The clearance portion is disposed at one end side in the first direction relative to an imaginary center line that passes through a center of the first heat transfer tube in a long side direction and that extends along a short side direction.

Abstract: An outdoor unit for an air-conditioning apparatus is configured to suppress damage on hairpin portions at an end portion of an outdoor heat exchanger due to freezing. The outdoor unit includes: an air passage defined inside a casing; an outdoor heat exchanger, which is installed in the air passage, and includes a plurality of heat exchange portions; an outdoor unit fan configured to introduce air into the outdoor heat exchanger; and an air passage blocking object installed in the air passage, and configured to block air flow. The outdoor heat exchanger includes: a heat transfer tube configured to allow refrigerant to pass therein; and a fin connected to the heat transfer tube. The heat transfer tube includes a hairpin portion, which is bent and folded back and to which no fin is connected. The air passage blocking object is configured to cover the hairpin portion.

Abstract: In a heat exchanger, each of a plurality of heat exchange members includes: a main body portion including a heat transfer pipe; and extending portions provided to the main body. The extending portions extend from ends of the main body portion in a third direction. When a dimension of the main body portion in the third direction is represented by La, a dimension of the extending portions in the third direction is represented by Lf, a dimension of a wall thickness of each of the heat transfer pipes is represented by tp, and a thickness dimension of each of the extending portions is represented by Tf, relationships: Lf/La?1 and Tf?tp are satisfied.

Abstract: Provided is a heat exchanger, including a plurality of heat exchange members arranged in a first direction so as to be spaced apart from each other. Each of the plurality of heat exchange members includes: a heat transfer pipe extending in a second direction intersecting with the first direction; and a heat transfer plate provided to the heat transfer pipe along the second direction. The heat transfer plate includes extending portions extending away from the heat transfer pipe in a third direction intersecting with each of the first direction and the second direction. The heat transfer plate is formed separately from the heat transfer pipe.

Abstract: Provided are a system of highly clean rooms capable of continuously maintaining high cleanliness of air of class 1 or above and supplying enough oxygen inside the room for several persons to live in and a wall adapted to the structure of such a system. The system of highly clean rooms 10 is provided with a living space 6 and a space 5 between the roof and the ceiling as subspaces of an enclosed space formed by a room 1a. One of the lateral walls of the room 1a is constituted of a wall 9 with an internal space 7, which is a hollow wall. The internal space 7 and the living space 6 are in contact via an inner wall 9a of the wall 9, and a gas exchange membrane 26 is stretched in the inner wall 9a.

Abstract: A room 100 in a building has a living etc. space 101 of volume V that is an enclosed space. Ventilation of an air flow F is performed from the outside to the living etc. space 101. Entering/exiting of air as an air current between the inside of the living etc. space 101 and the outside is eliminated, and at least a part of the boundary between the living etc. space 101 and the outside is configured from a gas exchange membrane 310 having a diffusion constant D, a thickness L, and an area A for gas molecules of interest. When air inside the living etc. space 101 is sufficiently agitated and the concentration of gas molecules constituting the air is made spatially uniform, ?(t) is controlled so as to vary according to ? ? ( t ) = ? o - BL AD ? ( 1 - exp ? ( - [ AD ? / ? L ] ? t ? / ? V ) ) ( 9 ) B(m3/s) is the gas consumption amount inside the living etc. space 101, ?1(t) is the gas concentration inside the living etc.

Abstract: A heat exchanger includes: a heat exchange unit group made up of a plurality of heat exchange units arranged in a row direction, the heat exchange units including a plurality of heat transfer tubes configured to allow refrigerant to pass therethrough, the heat transfer tubes being arrayed in a level direction, the level direction being perpendicular to the direction of air flow, and a plurality of fins stacked to allow air to pass therethrough in the air flow direction; and headers, disposed on both ends of the heat exchange unit group, the headers being connected with ends of the plurality of heat transfer tubes, the heat exchange unit group including one or more bend sections bent in the row direction, the headers including one header provided on one end of the heat exchange unit group in common for the plurality of rows of the heat exchange units, and a plurality of separate headers provided separately for the heat exchange units on the other end of the heat exchange unit group, the plurality of separate h

Abstract: Provided is a heat exchanger, including: a refrigerant distributor including: a gas-liquid separating portion having a function of separating a gas-liquid refrigerant mixture into a liquid refrigerant and a gas refrigerant; and a distributing portion provided to the gas-liquid separating portion. A plurality of heat transfer pipes connected to the distributing portion. The plurality of heat transfer pipes are arranged side by side in a first direction, and extend along a second direction intersecting with the first direction. When the refrigerant distributor is viewed along a direction orthogonal to each of the first direction and the second direction, a first space forming portion overlaps a region of the plurality of heat transfer pipes. When the refrigerant distributor and the heat transfer pipes are viewed along the first direction, a clearance is present between the gas-liquid separating portion and the heat transfer pipes.

Abstract: In a heat exchanger, each of a plurality of heat exchange members includes: a flat pipe; and a heat transfer plate integrated with the flat pipe along a longitudinal direction of the flat pipe. A width direction of each of the flat pipes intersects with a direction in which the plurality of heat exchange members are arranged side by side. Each of the heat transfer plates includes an extending portion extending outward in the width direction of each of the flat pipes from at least one of one end of a corresponding one of the flat pipes in the width direction and another end of the corresponding one of the flat pipes in the width direction. Each of the flat pipes has one or more flat pipe bent portions, each forming a groove extending along the longitudinal direction of the flat pipes.