A method for defrosting an evaporator, includes: (i) closing an outlet part that serves as a refrigerant outlet of the evaporator; (ii) closing an inlet part that serves as a refrigerant inlet of the evaporator; (iii) connecting the outlet part and the inlet part to one another; (iv) heating the evaporator. An evaporator, includes: an inlet part that serves as a refrigerant inlet; a first switching valve that is placed in the inlet part; an outlet part that serves as a refrigerant outlet; a second switching valve that is placed in the outlet part; a bypass pathway that connected the inlet part and the outlet part to one another; a horizontal pipe that is communicated with the inlet part; and a vertical pipe that connects the horizontal pipe and the outlet part to one another. A cooling apparatus can include the evaporator.

A heat exchanger module includes a skin condenser and a skin evaporator. The skin condenser includes an inner condenser plate, an outer condenser plate coupled to the inner condenser plate and a condenser tube channel formed on one of the inner condenser plate and/or the outer condenser plate. The evaporator includes an inner evaporator plate, an outer evaporator plate coupled to the inner evaporator plate, and an evaporator tube channel formed on one of the inner evaporator plate and/or the outer evaporator plate. The heat exchanger also includes an insulation layer extending between the inner condenser plate and the inner evaporator plate. Each of the plates that form the skin condenser and/or evaporator can be formed from different materials and/or have different material thicknesses to reduce heat transfer through the insulation layer from the condenser to the evaporator while also promoting heat transfer through natural convection with surrounding air.

The invention concerns an attachment device (3) for a heat exchanger (2) comprising a core (23) for exchanging heat between a first fluid and a second fluid, said core (23) being provided with collectors (21) for the first fluid, said exchanger (2) comprising a cylinder (25), said cylinder (25) and one of said collectors (21) allowing the passage of said first fluid from one to the other, said attachment device (3) comprising a body, which is set up in order to close said cylinder (25), and an extension which allows the core (23) to be secured to a holder (4).

The invention also concerns a cylinder (25) which comprises such an attachment device (3), a heat exchanger (2) which comprises such a cylinder (25) and a heat exchanging module which comprises such a heat exchanger (2).

The invention concerns an attachment device (3) for a heat exchanger (2) comprising a core (23) for exchanging heat between a first fluid and a second fluid, said core (23) being provided with collectors (21) for the first fluid, said exchanger (2) comprising a cylinder (25), said cylinder (25) and one of said collectors (21) allowing the passage of said first fluid from one to the other, said attachment device (3) comprising a body, which is set up in order to close said cylinder (25), and an extension which allows the core (23) to be secured to a holder (4).

The invention also concerns a cylinder (25) which comprises such an attachment device (3), a heat exchanger (2) which comprises such a cylinder (25) and a heat exchanging module which comprises such a heat exchanger (2).

A system for cryocooling an optical sensor on a satellite to a temperature below 200K with minimal vibration comprising a miniature conical rotary screw compressor comprising an inner element configured to only rotate around a first stationary axis and an outer element configured to only rotate around a second stationary axis so that both elements revolve with minimal vibration; with at least one of a) a length of at least one of the inner element and the outer element is between 10 mm and 100 mm; b) a diameter of at least one of the inner element and the outer element is between 2 mm and 45 mm; c) a compression ratio of the rotary screw compressor is between 1:2 and 1:20; and d) a shaft speed of the conical rotary screw compressor is between 1001 and 20000 revolutions per minute.

A system for cryocooling an optical sensor on a satellite to a temperature below 200K with minimal vibration comprising a miniature conical rotary screw compressor comprising an inner element configured to only rotate around a first stationary axis and an outer element configured to only rotate around a second stationary axis so that both elements revolve with minimal vibration; with at least one of a) a length of at least one of the inner element and the outer element is between 10 mm and 100 mm; b) a diameter of at least one of the inner element and the outer element is between 2 mm and 45 mm; c) a compression ratio of the rotary screw compressor is between 1:2 and 1:20; and d) a shaft speed of the conical rotary screw compressor is between 1001 and 20000 revolutions per minute.

A refrigeration system includes a rotary pressure exchanger fluidly coupled to a low pressure branch and a high pressure branch. The rotary pressure exchanger is configured to receive the refrigerant at high pressure from the high pressure branch, to receive the refrigerant at low pressure from the low pressure branch, and to exchange pressure between the refrigerant at high pressure and the refrigerant at low pressure, and wherein a first exiting stream from the rotary pressure exchanger includes the refrigerant at high pressure in the supercritical state or the subcritical state and a second exiting stream from the rotary pressure exchanger includes the refrigerant at low pressure in the liquid state or the two-phase mixture of liquid and vapor.

A refrigeration system includes a rotary pressure exchanger fluidly coupled to a low pressure branch and a high pressure branch. The rotary pressure exchanger is configured to receive the refrigerant at high pressure from the high pressure branch, to receive the refrigerant at low pressure from the low pressure branch, and to exchange pressure between the refrigerant at high pressure and the refrigerant at low pressure, and wherein a first exiting stream from the rotary pressure exchanger includes the refrigerant at high pressure in the supercritical state or the subcritical state and a second exiting stream from the rotary pressure exchanger includes the refrigerant at low pressure in the liquid state or the two-phase mixture of liquid and vapor.

Provided is a gas-liquid separator, including a connection pipe connected to a refrigerant pipe in the evaporator, the refrigerant pipe in which a two-phase refrigerant flows, a header connected to the connection pipe, wherein a gas refrigerant separated from the two-phase refrigerant flows inside the header, a bypass pipe connected to the header to guide a flow of the gas refrigerant to a compressor, a flow rate control valve installed at the bypass pipe, and a controller configured to control opening and closing of the flow rate control valve based on whether a preset condition is satisfied.

Provided is a gas-liquid separator, including a connection pipe connected to a refrigerant pipe in the evaporator, the refrigerant pipe in which a two-phase refrigerant flows, a header connected to the connection pipe, wherein a gas refrigerant separated from the two-phase refrigerant flows inside the header, a bypass pipe connected to the header to guide a flow of the gas refrigerant to a compressor, a flow rate control valve installed at the bypass pipe, and a controller configured to control opening and closing of the flow rate control valve based on whether a preset condition is satisfied.