A method for at least partially removing a contamination layer (24) from an optical surface (14a) of an optical element (14) that reflects EUV radiation includes: performing an atomic layer etching process for at least partially removing the contamination layer (24) from the optical surface (14a), which, in turn, includes: exposing the contamination layer (24) to a surface-modifying reactant (44) in a surface modification step, and exposing the contamination layer (24) to a material-detaching reactant (45) in a material detachment step. The optical element (14) is typically taken, before the atomic layer etching process is performed, from an optical arrangement, in particular from an EUV lithography system, in which the optical surface (14a) of the optical element (14) is exposed to EUV radiation (6), during which the contamination layer (24) is formed.

The invention relates to a heat recovery unit to transfer heat from a gray water source discharged from a bath or a shower to preheat fresh cold water supplying a bath, a shower, a boiler system or hot water heater. The heat recovery unit comprises an inner tube, an outer tube, a non-return valve, an anode, deflectors as well as associated piping and fittings. Fresh water from a pressurized public network or well flows through the inner tube while the gray water flows between the inner and outer tubes. The non-return valve installed in the fresh water pipe prevents contamination of the drinking water system. A translucent pipe may be installed in a section of the gray water piping system to detect any leaks. An insulated jacket may be placed around the unit to reduce heat loss. The heat recovery unit may be used in domestic, commercial, industrial and institutional buildings.

A laminated fluid warmer includes: a laminate including a target fluid layer having a plurality of target fluid channels through which a warming target fluid flows, and a warming fluid layer that is laminated on the target fluid layer and has a plurality of warming fluid channels through which a warming fluid for warming the target fluid layer flows; and a collection device that collects at least a part of the warming fluid accumulated in the plurality of warming fluid channels. The collection device includes a storage portion that receives the warming fluid flowing out from the warming fluid channel when collecting the warming fluid.

A heat exchanger includes a main pipe through which refrigerant flows, a plurality of tubes connected to the main pipe to allow refrigerant passing through the plurality of tubes to exchange heat with air, and a refrigerant distributor disposed between the main pipe and the plurality of tubes, to distribute refrigerant passing through the main pipe to the plurality of tubes. The refrigerant distributor includes an upstream structure connected to the main pipe and including a plurality of first distribution flow paths to which the refrigerant passing through the main pipe are distributed, and a downstream structure including a plurality of second distribution flow paths communicating with the plurality of first distribution flow paths, and a plurality of refrigerant outlets communicating with the plurality of second distribution flow paths so as to allow the refrigerant to be discharged to the plurality of tubes.

A heat exchanger (4) comprises a heat exchanger core (20) comprising first fluid channels (22) and second fluid flow channels (24) for exchange of heat between the first and second fluids. First and second manifold portions (42, 44) are provided to guide the first and second fluids between the first and second fluid flow channels (22, 249 and first and second fluid interface portions (48, 49) which comprise fewer channels than the heat exchanger core (20). The first manifold portion (42) includes at least one tunnel portion (46) extending through the second manifold portion (44) at an angle to the direction of second fluid flow. Hence at least part of the first fluid is directed through the inside of the tunnel portion while the second fluid passes around the outside of the tunnel portion. This enables more compact heat exchanger design.

A cooling device for a stator of an electrical machine, for fitting together with a hollow cylindrical laminated core of the stator, includes multiple cooling channels for conducting cooling fluid along the laminated core, and a fluid ring for provision on an end face of the laminated core. The fluid ring has two fluid ring channels for distributing the cooling fluid to the cooling channels and for receiving the cooling fluid from the cooling channels, and at least two cooling fluid connections for introducing and removing the cooling fluid into and from the fluid ring channels. The fluid ring channels have circumferential-angle-dependent flow cross-sections in the flow direction, in order to evenly distribute the cooling fluid to the cooling channels.

A shell and tube heat exchanger includes a tube bundle for passage of a first medium from a first inlet to a first outlet. A second medium flows through a flow space which surrounds the tube bundle. The tube bundle includes first tubes communicating with the first inlet, and second tubes communicating with the first outlet and fluidly connected to the first tubes. The first tubes define an outer enveloping surface which is predominantly adjacent to an enveloping surface of the second tubes. A separating body between the first inlet and a tubesheet which separates the flow space from the first medium prevents the first medium from flowing against the tubesheet and includes inlet tubes which bridge a compensation space between the separating body and the tubesheet and which protrude into the first tubes to direct the first medium into the first tubes while bypassing the tubesheet.

The present application provides an evaporator, including a heat exchange tube set and a distribution device. The heat exchange tube set includes a plurality of heat exchange tubes. The distribution device is provided on one end of the length direction of the heat exchange tube set such that the distribution device can distribute a refrigerant through heat exchange tube inlets at the end portions of the plurality of heat exchange tubes. The distribution device includes a distribution device housing, at least one receiving port, and at least one distribution member. The receiving port is provided on the distribution device housing, and the distribution member is provided in the distribution device housing. The distribution device housing is disposed around the heat exchange tube inlets at the end portions of the heat exchange tube set and seals the heat exchange tube inlets. The distribution member can receive the refrigerant through the receiving port. The distribution member is provided with a plurality of distribution ports such that the refrigerant in the distribution member can be sprayed through the plurality of distribution ports towards the heat exchange tube inlets of the heat exchange tube set. The evaporator of the present application can uniformly distribute the refrigerant to the plurality of heat exchange tubes of the heat exchange tube set by using a simple structure, thereby effectively ensuring the heat exchange efficiency of the evaporator.

A heat exchanger having a circulation guide, the heat exchanger comprising: a heat exchanger body; an inlet port, which is connected to a bottom end of the heat exchanger body; a discharge port which is connected to a top end of the heat exchanger body; a top body tube installed at a top end of an inside of the heat exchanger body; a bottom end plate installed at a bottom end of the inside of the heat exchanger body; and combustion pipes, which each have a top end connected to pass through a floor surface of the top body tube.

A heat exchanger is formed by stacking plates with each other. The heat exchanger includes a refrigerant receiving tank configured to receive a refrigerant, a refrigerant discharging tank configured to discharge the refrigerant that has heat-exchanged, and refrigerant passages in which heat exchange between the refrigerant and another fluid is performed. The refrigerant passages fluidly connect between the refrigerant receiving tank and the refrigerant discharging tank. The refrigerant receiving tank includes a swirl structure configured to generate a swirling component in a flow of the refrigerant in the refrigerant receiving tank.