Abstract: A head housing for curing of resin pipeline lining used in heads for curing inner pipeline resin linings with significantly increased heat dissipation efficiency, having at least one cooling passage (6), which length S is more than twice the length L of the longitudinal part (1) of this housing.

Abstract: An exposure apparatus comprising a holding part for holding an electric discharge lamp, the electric discharge lamp includes an electric discharge tube which covers an electric discharge space in which a pair of electrodes are disposed to face each other, a socket provided on one end of the electric discharge tube, a metal member which guides one of the pair of electrodes into the socket, wherein an opening for ventilation is provided in a bottom of the socket, the holding part includes a ventilation pipe to form a path for ventilation through the opening in the bottom of the socket, and a cooling part for cooling the metal member by supplying a cooling medium to the metal member through the ventilation pipe.

Abstract: A stationary anode for an X-ray generator, in particular of an X-ray imaging device or an X-ray therapy or spectroscopy device, includes a main anode body and an internal cooling duct, running in the axial direction, for conveying a cooling fluid to a heat exchange surface of the main anode body. A nozzle, disposed at the end of the cooling duct, is inventively positioned with respect to the heat exchange surface via stop elements such that, between the heat exchange surface and the nozzle, a gap is formed which extends over an angular range of 360° about the axial direction.

Abstract: According to one embodiment, an X-ray tube assembly includes a cathode, an anode target, a joint including an inflow part into which a coolant flows, a first cylindrical pipe to which the joint is connected at one end, and the anode target is joined at an outer bottom part of the other end, a second cylindrical pipe whose first end part is fitted into the inflow part, and whose second end part is arranged to eject the coolant toward the bottom part of the first cylindrical pipe, the second cylindrical pipe being placed inside the first cylindrical pipe and an elastic member provided between the first end part and the first cylindrical pipe.

Abstract: A cooling apparatus for cooling a light source unit is provided. The cooling apparatus includes a cooling unit provided outside a path of light from the light source unit, and a heat pipe configured to connect a heat generating portion of the light source unit and the cooling unit. The heat pipe also serves as an electrode wire of the light source unit.

Abstract: An electrode holder for an arc plasma torch includes an elongate holder body. The holder body includes a holder end for receiving an electrode and a hollow interior. An internal thread is positioned in the hollow interior for screwing in a rear end of said cooling tube. A cylindrical inner surface adjoins the internal thread for centering the cooling tube relative to the electrode holder.

Abstract: Embodiments disclosed herein include an abatement system for abating compounds produced in semiconductor processes. The abatement system includes a plasma source that has a first plate and a second plate parallel to the first plate. An electrode is disposed between the first and second plates and an outer wall is disposed between the first and second plates surrounding the electrode. The plasma source has a first plurality of magnets disposed on the first plate and a second plurality of magnets disposed on the second plate. The magnetic field created by the first and second plurality of magnets is substantially perpendicular to the electric field created between the electrode and the outer wall. In this configuration, a dense plasma is created.

Abstract: Embodiments disclosed herein include a plasma source for abating compounds produced in semiconductor processes. The plasma source has a first plate and a second plate parallel to the first plate. An electrode is disposed between the first and second plates and an outer wall is disposed between the first and second plates surrounding the cylindrical electrode. The plasma source has a first plurality of magnets disposed on the first plate and a second plurality of magnets disposed on the second plate. The magnetic field created by the first and second plurality of magnets is substantially perpendicular to the electric field created between the electrode and the outer wall. In this configuration, a dense plasma is created.

Abstract: A cooling tube for an arc plasma torch, comprising an elongate body with an end which can be arranged in the open end of an electrode, and a coolant duct extending therethrough, characterized in that at said end there is a bead-like thickening of the wall of the cooling tube pointing inwards and/or outwards, and an arrangement of a cooling tube for an arc plasma torch, comprising an elongate body with a rear end which can be releasably connected to an electrode holder of an arc plasma torch, and a coolant duct extending therethrough, and an electrode holder for an arc plasma torch, comprising an elongate body with an end for receiving an electrode and a hollow interior, and characterized in that on the outer surface of the cooling tube at least one projection is provided for centring the cooling tube in the electrode holder.

Abstract: A transmission x-ray tube comprising an end window hermetically sealed to a flexible coupling. The flexible coupling can allow the window to shift or tilt in one direction or another direction to allow an electron beam to impinge upon one region of the window or another region of the window. A method of utilizing different regions of an x-ray tube target by tilting an x-ray tube window at an acute angle with respect to an electron beam axis to cause an electron beam to impinge on a selected region of the window and tilting the window in a different direction to allow the electron beam to impinge on a different selected region of the window.

Abstract: A plasma electrode for a plasma cutting device consisting of a hollow cylindrical electrode body at whose front side a centric core holder directed in the interior of the electrode, arranged on the front side for the mounting of an emitting electrode core is arranged, wherein in the interior of the electrode body a cooling tube is arranged, through which an axial coolant flow flows, characterized in that the cooling tube is held position secured at least partially with its face on the core holder.

Abstract: The excitation source consists of at least three identical electrodes arranged symmetrically in relation to the axis of the central tube, which supplies an analytical sample, and electrode cooling agent supply and removal systems. The electrodes are mounted in an electrically isolated metal housing so that the electrode tops are placed at the central tube outlet, and their ends are shorted in the power supply point with the microwave connections embedded in the housing on the extension of the electrode longitudinal axis and the connections are coupled with the microwave power source, the length of each electrode is ¼ L, where L is the length of the microwave. Each electrode has a hollowed longitudinal flow chamber for the cooling agent connected with metal side tubes, which supply and remove the cooling agent, while outside tube ends are electrically shorted with the housing.

Abstract: A light source device includes a light emitting tube having a light emitting section configured to emit light, a first reflecting member configured to reflect the light emitted from the light emitting section, and a rectifying member disposed between the light emitting section and the first reflecting member, and configured to rectify a cooling fluid configured to cool the light emitting tube, and the rectifying member includes a rectifying surface configured to guide the cooling fluid flowing toward the rectifying member to the light emitting section, and a pair of standing surfaces standing from both ends of the rectifying surface.

Abstract: The excitation source consists of at least three identical electrodes arranged symmetrically in relation to the axis of the central tube, which supplies an analytical sample, and electrode cooling agent supply and removal systems. The electrodes are mounted in an electrically isolated metal housing so that the electrode tops are placed at the central tube outlet, and their ends are shorted in the power supply point with the microwave connections embedded in the housing on the extension of the electrode longitudinal axis and the connections are coupled with the microwave power source, the length of each electrode is ¼ L, where L is the length of the microwave. Each electrode has a hollowed longitudinal flow chamber for the cooling agent connected with metal side tubes, which supply and remove the cooling agent, while outside tube ends are electrically shorted with the housing.

Abstract: Provided is an ion generating device for an air-conditioner duct, which can be easily attached to the inside of an existing air conditioner duct and can ensure a desired ion generation quantity. The ion generating elements of the sub-units (3, 4, 5) of the ion generating device are connected to the drive circuit of the ion generating device main unit (2), and are driven by the drive circuit.

Abstract: A tube lamp has a tubular portion that serves both as a light guide for energy from a solid state source and as a container for a material bearing a nanophosphor that is pumped by the energy from the source as the energy traverses the light guide. However, the tubular portion of the light guide also allows emission of light produced by the phosphor when excited. The material with the nanophosphor dispersed therein may appear either clear or translucent when the lamp is off and the nanophosphor is not excited by energy from the source.

Abstract: A lamp holder for a dielectric barrier discharge (DBD) lamp (1), especially for use in a treatment system or reactor or housing or in an irradiation apparatus, for radiating a medium like a fluid and/or a gas and/or a solid material by means of the DBD lamp (1) is disclosed. The holder substantially comprises two end caps (21, 31) at the axial ends of the lamp (1) and an inner electrode (23, 24; 33, 34) with a screw fitting (SF) for exerting an axial pressure on both axial ends of the lamp (I) via both end caps (21, 31) and with axial bores (25, 35) into an inner volume (14) for guiding especially a cooling medium and for electrically contacting an inner tube (II) of the lamp (1). The holder has a comparatively simple construction and can easily be assembled. Furthermore, even larger tolerances of the lamp length can be compensated and a reliable sealing of the inner volume (14) against the outside of the lamp (1) is achieved.

Abstract: The subject of the present invention is a lamp-ballast-system (1), especially a dielectric barrier discharge (DBD-) lamp-ballast-system for generating and/or emitting a radiation of ultraviolet (UV-)-light comprising: a lamp (2) having means for electrical contacting and a ballast (3) having a housing (4) accommodating at least a high-voltage part and a lamp support, connectable to and supplying the DBD-lamp (2) at least with electricity, whereby the electrical connection (5) between the DBD-lamp (2) and the ballast (3) is arranged cable-free.

Abstract: A light source apparatus includes a light emitting chip which generates light and heat when energized via a first electrode and a second electrode, wherein the first electrode is a base on which the light emitting chip is directly packaged.

Abstract: Apparatus for connecting an HV cable to the cathode of an X-ray tube is provided with a housing disposed for attachment to the X-ray tube, and a quantity of epoxy or other electric insulating material contained within the housing. The epoxy serves to insulate the exposed end portions of the HV cable conductors, which extend beyond the cable insulation for insertion into the X-ray tube casing. The connector apparatus further includes a heat transfer device, such as a heat pipe, which extends long the cable within the connector housing. A quantity of working fluid contained in the heat transfer device is disposed for bi-directional movement along the device to transfer heat from a first location within the insulating material to a second location proximate to the housing.

Abstract: An electrodeless lamp comprises an envelope containing a fill and a substance for facilitating the starting of the lamp. An outer tube is secured to an outside portion of the envelope in proximity to the given region and an inner tube is disposed within the outer tube such that a fluid passageway is defined between an inner surface of the outer tube and an outer surface of the inner tube. A hollow retractable electrode is provided within the inner tube, the electrode having a first position in which its tip portion is in proximity to the given region of the envelope when the lamp is being started and a second position in which the tip portion is away from the envelope after the lamp is started. A source of cooling fluid is operably connected to the hollow electrode such that the cooling fluid is forced through the hollow electrode and exhausted through the fluid passageway.

Abstract: A discharge lamp provided with an anode of the water cooled type achieves advantageous cooling directly connected a tungsten tip piece to a tip of a body element of the anode that is formed of copper has a water cooling arrangement therein, by having a maximum outer diameter of the tungsten tip piece about equal to an outer diameter D (mm) of the body element, and by maintaining the relationship between the outer diameter D and the thickness of the tungsten tip piece L of: 0.2.ltoreq.L/D.ltoreq.0.5.

Abstract: The present invention provides a double helix coupled vane forward wave crossed-field amplifier utilizing backwall cooling and vane channel cooling in the RF slow wave circuit. Backwall channel cooling is provided for the majority of the anode vanes. Additional cooling is provided exclusively for the output vanes via individual coolant carrying passages in each output vane. The coolant carrying passages are machined into each standard double helix coupled output vane to create a vane channel in the shape of a "U". A tube formed in a corresponding U-shape is inserted and brazed to the machined vane. The vane assembly is then attached to the anode body of which the backwall has holes formed to accept the tubes from each vane. Divided backwall coolant channels are brazed to the outside of the anode, thereby placing in fluid communication the coolant channels to the tubes.

Abstract: A fluid optical system for focusing all entering light whatever its direction and incidence, and having an entrance surface through which the light enters. The optical system has a volume having an optical shape generated by a logarithmic spiral so that the focusing occurs for light beams entering the entrance surface from any direction through any point of the entrance surface. There flows in the optical shape a fluid which is maintained in forced circulation to form a fluid optical system, and which is forced to enter the optical system tangentially to the optical shape and adjacent to the entrance surface which is arranged so that initial circulation is tangential and laminar. Inside the optical system, the fluid has a centripetal rotation movement until it exits through a cone end of the optical shape, thus draining off calories.

Abstract: The present invention provides a double helix coupled vane forward wave crossed-field amplifier utilizing individually cooled vanes in the RF slow-wave circuit. Specifically, a double helix coupled vane is machined to create a channel in the shape of a "U" on one side of the vane. A vane coolant tube formed in a corresponding U-shape is inserted and brazed to the machined vane. The vane assembly is then attached to the anode body of which the backwall has holes formed to accept the coolant tubes from each vane. Divided backwall coolant channels are brazed to the outside of the anode, thereby placing in fluid communication the coolant channels to the vane coolant tube. Accordingly, coolant is cycled through each vane tube and individual vanes of the anode are thus cooled.

Abstract: A cooled plasma source for producing ions by electrical discharge. A cooled plate is positioned in the chamber of the plasma source for blocking thermal radiation from an electron-emitting cathode. The presence of the cooled plate results in significantly decreased substrate temperatures, as compared to use of conventional plasma source apparatus. As a result, the cooled plasma source may be used for treatment of heat-sensitive plastic substrates.

Abstract: In the cooling of UV high-power radiators, the cooling of the inner electrodes (5) which are at high tension potential is critical insofar as it is necessary to use fully demineralized water or oil for this purpose. Since a cooling body (9) must in any event be employed for the external cooling, this cooling body is utilized at the same time as heat exchanger for the internal cooling.

Abstract: A target assembly for a projection cathode ray tube is provided wherein the target member is cooled by convective fluid heat transfer occurring within and around a partially hollow support shaft screw. The target member is a solid block of relatively high, thermally conductive material, such as aluminum, coated with an electron beam sensitive material. The shaft screw also comprises relatively high thermally conductive material, such as copper, and has an internal passage leading from a source of cooling fluid, such as dry air, to a annular array of ports located in a distal portion of the supporting shaft screw. The distal portion of the shaft screw has a flaring cross section for increased heat transfer. A bellows encloses the distal portion forming a passageway so as to cause the cooling fluid to also flow along the external surface of the shaft screw. This arrangement adds to the effective convective heat transfer from the shaft screw to the cooling fluid.

Abstract: An arc lamp of the type having an internally integral reflector including an electrode which has an inlet passageway which deliver fluid to a point below the electrode tip and also has an outlet passageway to withdraw fluid from the electrode. The arc lamp further includes a housing which has an internal cavity which houses the body of the arc lamp. The internal cavity of the housing has a spiral passageway which directs fluid around the body of the lamp for improved cooling efficiency.

Abstract: An improvement to an existing crossed-field amplifier is shown which includes the replacement of an existing thermionic emitter with a larger platinum emitter. The platinum emitter is cooled from a surface opposite to the surface upon which a high voltage is applied to permit the form of the existing crossed-field amplifier to be maintained.

Abstract: The invention relates to an apparatus to perform plasma welding, by providing a cooling water temperature detector at the inlet side of cooling water in the plasma welding torch, controlling the temperature at the inlet side of the cooling water running into the plasma welding torch at a set temperature of more than 4.degree. C. and less than 18.degree. C., starting a plasma arc when the temperature of the cooling water reaches a specified point after starting to pass the cooling water, and moving the base metals and the torch relatively upon lapse of a specified time allowed to form a keyhole after start of the plasma arc.

Abstract: To cool the diaphragm of a spectral discharge lamp having an anode and a cathode between which a discharge is established, which discharge is controlled by the diaphragm, a fluid supply and removal duct is connected to a cooling circuit in or on the diaphragm structure to supply, for example, water to cool the diaphragm. The tube or bulb of the lamp may be in form of a jacketed enclosure through which cooling water is conducted, preferably in the same supply and removal circuit as that for the diaphragm structure.

Abstract: A crossed field amplifier including a linear, ladder type slow wave device ncluding an array of closely spaced parallel U-shaped rungs with a pair of oppositely wound helices running side-by-side inside said array, and a pair of trimmers running along each side of said array of rungs, the trimmer height at the input or cathode end of said slow wave structure being increased compared to its height for the remainder of said slow wave device.

Abstract: Typically, a bottom of a cup-shaped electrode opposes to that of a similar electrode through a predetermined gap and in a mixture of helium and hydrogen. A step-up transformer connected across an AC source through a resistor applies a voltage in excess of a discharge breakdown voltage for the gap across the electrodes to cause a pilot glow discharge between them before the source voltage reaches a glow hold minimum voltage for the electrodes. A rectified voltage resulting from a transformer connected across the resistor turns a bidirectional triode thyristor on to apply the source voltage across the electrodes through the conducting thyristor. This smoothly transits the pilot glow discharge to a glow discharge between the electrodes. The latter discharge heats a liquid forcedly flowing along inner surfaces of the electrodes. Also an auxiliary electrode can be operatively coupled to the electrodes to cause similarly a pilot glow discharge between it and either one of the electrodes.

Abstract: In rotating anode X-ray tubes it has not been the practice to provide anode cooling because of problems in arranging coolant flow. A further problem which has arisen, particularly in tubes for computerized tomography which should have precisely defined focal spots, is off-focus radiation apparently resulting from back scattered electrons hitting the tube target away from the focal spot. It is here proposed to provide a rotating anode X-ray tube with a shroud surrounding and close to at least part of the anode. This is extended towards the electron gun with an aperture through which the electron beam travels and an X-ray emissive window. The shroud collects back scattered electrons and can also be fluid cooled. The window provides some collimation and the edges can be shaped to restrict the focal spot as viewed away from the main X-ray beam.

Abstract: A microwave device of the magnetron type comprises an anode block with straps which are located with respect to one another along the axis of the block and are electrically connected to respective vanes of resonators of the block, these vanes having like polarity at the .pi.-mode of oscillations. The anode block is provided with cooling channels adapted to cool the vanes of the resonators and straps, said channels communicating with at least one chamber designed to distribute a liquid coolant and with at least one chamber designed to collect the liquid coolant, said chambers being rigidly connected with the anode block and provided with a hydraulic coupling between them. The straps of the anode block are implemented in the form of ring-like tubes.

Abstract: A large cathode structure having a diameter on the order of 50 cm for producing uniform plasmas in a magnetic field. The cathode is oxide-coated and indirectly heated by a plurality of heater wires disposed in insulating tubes arranged parallel to each other. The cathode is pressed against the insulating tubes thereby to maintain it substantially flat in spite of expansion and contraction due to the heating and cooling effects. Optionally, the insulating tubes carrying the heater wires may be backed up by a second set of insulating tubes disposed at right angles to the first set. An annular ring is disposed about the cathode and is provided with tungsten springs for forcing the cathode against the heater tubes. This ring may additionally serve as a heat shield and maintain the temperature more uniform about the periphery of the cathode. For large cathodes, the structure may be water cooled by the provision of two copper tubes through which the water flows.

Abstract: Magnetically focussed tube having a gate cooler separate from the anode cooler and of higher power capacity than previous magnetically focussed tubes. Other structural features include simplified anode and cooling jacket and heat barrier at ends of cathode.

Abstract: A gas-discharge chamber electrode is proposed, comprising a hollow metal member with an emitting portion on the gas-discharge side and with coolant pipes. The hollow metal member is coated on the outside, except for the emitting portion, with a high-temperature dielectric. The electrode system includes at least two such electrodes.

Abstract: A cathode structure for a high power laser is formed from a first sheet of a hard metallic material such as molybdenum, which is joined to a second sheet of the same material by brazing, these first two sheets being brazed to a support structure of the same material. The first two sheets have a plurality of side by side longitudinal channels formed therein, the channels of one of these sheets being positioned between the channels of the other sheet (in a 180.degree. spatial phase relationship therewith). Crosswise channels are provided along opposite edges of both of the sheets to provide fluid communications to the opposite ends of the longitudinal channels. A cooling liquid such as water is fed to the transverse channels, and circulated through the longitudinal channels in parallel to effect efficient cooling of the cathode.

Abstract: The cylindrical peripheral wall (5) of a rotating hollow body mounted on a haft (1) driven by an electric motor within the stem casing of an X-ray tube is cooled with water supplied and removed respectively through co-axial ducts in the drive shaft, distributed by radial ducts in one end face of the rotary body to a ring duct and gathered from a ring duct at the other end face through another set of radial ducts leading back to the shaft. Between the two ring ducts the cooling medium flows through helical cooling ducts running parallel to each other and at an angle of about 15.degree. to the edge boundaries of the cylindrical operating surface. These ducts are formed on the outside by the anode peripheral wall material itself and on the inside by a stainless steel insert. The anode is degassed when its structure is soldered or brazed together in high vacuum at 1000.degree. C.

Abstract: A turbomolecular pump coaxial with the drive shaftof a rotary anode in an ray tube is provided between the radial seal of the drive shaft and the high vacuum space surrounding the rotary anode. A pot-shaped shell mounted on the drive shaft where the latter passes through its bottom carries the rotor vanes, while the stator vanes are fixed on the tube casing. In order that the anode may be driven with the built-in electric motor located within the tube casing between the drive shaft bearings, at the high speed desirable for the turbomolecular pump, the rotary anode is cooled by water flowing through a set of closely adjacent helical ducts just inside of the working anode surface, running at a pitch of 10.degree. to 15.degree., fed with cooling liquid from radial ducts and a ring duct along one end face of a rotary anode and drained by another ring duct and another set of radial ducts along the other face of the rotary anode.

Abstract: A target for a fusion neutron generator consisting of planar arrays of parallel tubes through which a cooling liquid is circulated. The target is relatively thin, and can be used to intercept two ion beams simultaneously, one on the front and the other on the back of the target. Two mixed ion beams, each containing a mixture of deuterium and tritium ions are accelerated into both sides of the water-cooled chromium plated copper-tube target whereby reactions occur yielding 14 MeV neutrons. At typical operating conditions of 170 keV and 300 mA total beam current, the neutron yield with a mixture of deuterium and tritium gas is approximately 6 .times. 10.sup.12 n/sec for an effective beam spot of 5.5 centimeters diameter.

Abstract: An X-ray tube for analytic use comprises a bottomed cylindrical nozzle which is formed at the bottom with a slit having substantially the same shape and size as that of a focus formed on an electron-impact surface of an anode target. A pair of recesses are formed out in the backside surface of the anode. The nozzle is provided on its outer periphery with a pair of engaging members fitted into the recess, respectively, to prevent the rotation of the nozzle relative to the anode target. Consequently, the nozzle is detachably fitted to the anode and rotated substantially together with the anode thus resulting in a sure alignment of the slit of nozzle with the focus of target.

Abstract: A plasmatron comprises a casing wherein a water-cooled cylindrical hollow electrode is placed so that its bottom faces the power lead-in and the butt contacts an annular insulating vortex generator which contacts a water-cooled nozzle. The casing also houses a lead-in coil enveloping the cylindrical hollow electrode and positioned with a certain clearance between the electrode and the lead-in coil. One end of the coil is connected to the power lead-in and the other to the butt of the cylindrical hollow electrode.

Abstract: There is disclosed herein an electrode type glow discharge apparatus, such as that used for sputtering material from a cathode to provide a coating or the like on materials such as a substrate or substrates. Several exemplary embodiments are disclosed involving various combinations of constructural features including a flanged or spool type cathode, anode placement with respect thereto, provision of internal and/or external magnetic fields with field lines close to and substantially parallel with the barrel of the cathode, insulator placement, efficient cooling for anode and cathode, and the like. Furthermore, the assembly is constructed in a manner such that the same can be readily disassembled for enabling change of cathode materials and for cleaning cooling fluid passageways of the cathode and anode. Embodiments are described wherein at least a portion of the cathode may be in the form of a continuously moving member, such as a wire.

Abstract: A magnetron comprising a large vane-type, double-strapped anode structure with the vanes being cooled by liquid flowing in a channel immediately behind the surface bombarded by electrodes and the two pairs of straps passing through openings in the vanes, a liquid cooled secondary-emission cathode positioned centrally of the anode, said cathode incorporating a starting filament connected to a heating current power source, means for engendering an axial magnetic field in the region between anode and cathode, and power output means connected to at least one slot between vanes, said means including a coupling slot, a ridge waveguide transition connected to said slot and a window between the transition and an output waveguide.

Abstract: There is disclosed herein an electrode type glow discharge apparatus, such as that used for sputtering material from a cathode to provide a coating or the like on materials such as a substrate or substrates. Several exemplary embodiments are disclosed involving various combinations of constructural features including a flanged or spool type cathode, anode placement with respect thereto, provision of internal and/or external magnetic fields with field lines close to and substantially parallel with the barrel of the cathode, insulator placement, efficient cooling for anode and cathode, and the like. Furthermore, the assembly is constructed in a manner such that the same can be readily disassembled for enabling change of cathode materials and for cleaning cooling fluid passageways of the cathode and anode. Embodiments are described wherein at least a portion of the cathode may be in the form of a continuously moving member, such as a wire.

Abstract: An axial ion source comprising a tubular anode having an axis XX, at the two ends of which there are placed a cathode located along said axis XX and anticathode which comprises a circular plate having an axis YY parallel to the axis XX, this plate being able to revolve about this axis YY. A device controls the sequential rotation of the anticathode about the axis YY, the rotation of the anticathode enabling a new intact surface to be presented, when necessary, at the end of the anode. A cooling fluid can circulate in the grooves equipping the plate.