76 results about "Boiling heat transfer" patented technology

The invention provides a steam generator heat transfer pipe dirt growth simulation and boiling heat transfer test device. The device comprises a simulation heat transfer pipe system, a reaction kettle system and a sliding thermocouple system, dirt growth speed regulation and control of a compact layer and a sparse layer of the heat transfer tube are realized through direct electric heating and increase of Fe ion concentration, and the problems of slow growth and large difference between dirt pore distribution and a power station in a traditional dirt experiment are solved; measurement of data at multiple positions in the circumferential direction of multiple heights is achieved through fine control of the sliding thermocouple, the reliability and repeatability of the data are verified through mutual verification of the data, and the repeatability and reliability of the data can be analyzed under the same working condition in combination with dirt observation and sampling analysis after an experiment. And a reliable coupling relationship between dirt growth and boiling heat transfer characteristics is obtained.

The invention discloses a subtractive etching micro-nano multistage rough structure copper surface for strengthening boiling heat transfer and a preparation method thereof, and relates to the technical field of micro-nano composite structure strengthening phase change heat transfer. The etched micro-nano multistage coarse structure completely covers the surface of the copper substrate, the micro-nano multistage coarse structure comprises micron-scale concave cavities, nano-scale concave cavities / holes and nano-scale granular bulges, and the micron-scale concave cavities, the nano-scale concave cavities / holes and the nano-scale granular bulges jointly form a multistage structure; performing ultrasonic cleaning on the target metal substrate by using a cleaning solution; and a mixed aqueous solution of ammonium persulfate and chlorate is used as an etching solution, and the cleaned target metal substrate is left to stand in the etching solution for etching. And after the etching is finished, cleaning to obtain the etched micro-nano composite rough structure surface. Ammonium persulfate and chlorate are used as solutes, and the mass ratio of the solutes to the solvent is 1: 3. The mass ratio of the ammonium persulfate to the chlorate in the solute is (1: 9)-(3: 7). The method has high production efficiency, shows good thermal stability in a boiling test, and is beneficial to industrial large-scale application and production.

The invention provides a multi-physics-field coupled core particle microchannel boiling heat exchange experiment testing device and testing method, and belongs to the field of boiling heat exchange experiment testing devices. According to the invention, a laser thermal control module, a reflection temperature measurement module, a particle velocity measurement module, a three-dimensional micro-control module, a stress test module, a sound field test module and an electric field test module are creatively integrated, and flexible combination and active control of each physical field are realized through standardized interfaces. Local point heating is achieved through pulse laser, non-contact transient surface temperature analysis is achieved through a heat reflection method, a micro-nano scale phase change flow field is analyzed through a PIV system, local thermal stress is measured through an embedded film strain gauge set, and automatic alignment and cooperative measurement of all modules are achieved in combination with a high-precision piezoelectric displacement table. Through modular design and system integration, accurate coupling and cooperative measurement of multiple physical fields of light, sound, heat, force and flow on the core particle scale are realized.

The present invention discloses a composite microstructure surface that utilizes microtubes and micropores to synergistically enhance boiling heat transfer, comprising a microcolumn matrix and a plurality of microcolumn units distributed in an array on the microcolumn matrix. The microcolumn unit is composed of a plurality of microcolumns distributed in an array, and each microcolumn has microtubes symmetrically arranged on each side wall and micropores symmetrically arranged on the top. By adding micropores on the top surface of the microcolumn, the number of vaporization cores on the microstructure surface is effectively increased, the superheat of the surface is reduced, and thus the boiling heat transfer coefficient of the surface is improved; secondly, microtubes are provided on each side wall of the microcolumn, and by utilizing the interaction between microcolumns, micropores and microtubes in regulating the gas-liquid behavior during the boiling process, a multi-directional rehydration system is established from the rehydration channel to the microcolumn unit groove and the microtube rehydration, thereby enhancing the rehydration capacity of the surface, increasing the critical heat flux density of the surface, delaying the occurrence of boiling crisis, and achieving synergistic enhancement of the boiling heat transfer performance of the microstructure surface.

The application belongs to the technical field of hydrogen liquefaction, and provides a test platform and method for falling film boiling heat transfer characteristics of non-azeotropic refrigerant for liquid hydrogen, which comprises a gas filling system, a pre-cooling circulation system, a cryogenic circulation system and a falling film boiling test platform; the outlet and the inlet of the gas filling system are connected with the inlet and the outlet of the falling film boiling test platform through pipelines; the pipeline between the outlet of the gas filling system and the inlet of the falling film boiling test platform passes through the pre-cooling circulation system and the cryogenic circulation system; the pre-cooling circulation system and the cryogenic circulation system provide temperature conditions for hydrogen liquefaction; the real situation under the pre-cooling and cryogenic circulation systems is comprehensively considered; accurate measurement of temperature and pressure is realized; reliable data basis is provided for evaluation and optimization of the flow and heat transfer characteristics of the non-azeotropic refrigerant for liquid hydrogen; and the falling film boiling heat transfer characteristics of the non-azeotropic refrigerant for liquid hydrogen can be fully understood.

The present application relates to a kind of slab continuous casting high temperature casting blank surface temperature on-line detection method, belong to slab continuous casting technical field, comprising the following steps: S1: based on film temperature sensor production detection piece and measuring disc, and according to process requirement in corresponding two cooling zone sector segment clamp roll installation;S2: local transient heat conservation analysis is carried out to temperature measurement node, obtains the heat balance equation of considering conduction, convection and radiation heat transfer mode;S3: based on single node temperature time series discrete algorithm and according to temperature detection value, the heat balance equation is carried out numerical calculation, to reconstruct the actual temperature of the side above water film on slab surface is determined;S4: boiling heat transfer mechanism theory analysis is carried out, determines its corresponding critical characteristic temperature and the heat transfer mode where it is;S5: under stable film boiling heat transfer mechanism, according to classic flat plate temperature analytical theory, combined with the temperature of the side above water film on slab surface obtained again reconstruction calculation, to finally obtain the real temperature value of slab surface.

The invention discloses a heat transfer calculation method for pulsating heat pipes with adjustable inclination angles and liquid filling rates. The heat transfer performance of the pulsating heat pipes with different inclination angles and liquid filling rates is researched by adopting a numerical method; calculating the heat transfer process by solving the energy equation of the steam bomb and the energy and momentum equation of the liquid bomb, so as to predict the pulsation phenomenon of the working medium in the pulsating heat pipe; on the basis of a momentum heat mass transfer model, calculating the phase change heat transfer capacity through film condensation and a down-flow film boiling heat transfer coefficient, investigating the influence of different inclination angles on the liquid film thickness and the down-flow film speed, and increasing the influence of the down-flow film on the liquid elastic length; and the liquid bomb pulsation condition of the pulsating heat pipe under different inclination angles and different liquid filling rates is researched, and then the heat transfer performance of the pulsating heat pipe is calculated. The working heat transfer performance of the pulsating heat pipes with different inclination angles and liquid filling rates and the motion state of the working medium are analyzed and calculated, and guidance is provided for parameter development and engineering application of the pulsating heat pipes.

The invention discloses a single-sintering porous metal mold with different pore diameters for boiling heat exchange, and relates to the field of preparation equipment of porous metal for boiling heat exchange. The die comprises an outer die sleeve, a lower die base and three functional pressure heads, specifically, basic metal powder is compacted through a basic pressure head with a flat end face, then pore channels are pressed out through a pore-forming pressure head with thin cylindrical protrusions, finally, the pore channels are filled with powder with different particle sizes through a filling pressure head with matched through holes, and finally porous metal structures with different pore diameters are obtained through single-time sintering. The preparation process of porous metal with different pore diameters is simplified, the cost is reduced, pore collapse caused by secondary hole machining is avoided, and meanwhile the nucleation efficiency and the heat exchange performance of boiling heat exchange can be remarkably improved through the porous structures with different pore diameters.

This invention discloses a modular low-voltage switchgear suitable for smart grids, belonging to the field of low-voltage switchgear technology. It includes a cabinet with multiple module slots inside, each containing multiple auxiliary heat transfer components. Drawer units are installed within the module slots, and each drawer unit is equipped with a breathing heat dissipation unit. This invention replaces the rigid sealing structure with a multi-layer corrugated metal diaphragm assembly. It utilizes the corrugated elastic compression to absorb impact energy, automatically quenching flames through interlayer slits, and leverages the evaporation and condensation cycle of the phase change working fluid to achieve efficient heat conduction without occupying the internal installation space of the drawer unit. This solves the problem of limited heat dissipation capacity in explosion-proof switchgear. Furthermore, by mixing magnetic particles into the liquid phase change working fluid, the boundary layer is disturbed under the drive of the auxiliary heat transfer components, promoting bubble generation and detachment, significantly enhancing the nucleation boiling heat transfer coefficient.

The application discloses a high-flux heat exchange device based on a thermo-chemical reaction auxiliary, which comprises a heat exchange chamber and a chemical phase change working medium. The chemical phase change working medium comprises a liquid cooling base fluid and a reversible thermal decomposition solute. The thermal decomposition temperature threshold of the reversible thermal decomposition solute is lower than the physical boiling point of the liquid cooling base fluid under the current environment. When the temperature or pressure of the heat exchange surface reaches the thermal decomposition temperature threshold, the reversible thermal decomposition solute undergoes an endothermic decomposition reaction on the heat exchange surface, rapidly generates a large number of non-condensable bubbles and high-frequency separates, thereby triggering strong local micro-convection disturbance of the fluid and absorbing a large amount of chemical decomposition heat, and finally achieving heat dissipation of the heating element. The application accelerates the transfer of wall heat by using a thermo-chemical reaction, and improves the separation rate of bubbles at the solid-liquid interface, breaks the engineering resistance that bubbles are difficult to nucleate and efficiently separate in traditional boiling heat transfer, and realizes rapid and large absorption and transfer of the combined chemical reaction heat of the solute and the latent heat of vaporization of the base fluid.

The invention discloses a high-pressure lower pool boiling experiment device and experiment system to meet the requirements of high-pressure lower pool boiling heat transfer performance test and visual shooting. The experimental device comprises a boiling container main body arranged between an upper cover plate and a lower cover plate, a heat conductor and a heat insulator, a boiling pool is arranged in the boiling container main body, an auxiliary electric heater is arranged in the boiling pool, and a visual window is arranged on the side face of the boiling container main body; the upper end of the boiling container body is hermetically connected with the upper cover plate, a heat conductor is arranged at the lower end of the boiling container body corresponding to the boiling pool, the heat insulator is hermetically arranged between the heat conductor and the boiling container body, and a pool boiling electric heater is mounted in the heat conductor; and a test piece connected with the heat conductor and used for reflecting heat transfer performance and bubble behavior is arranged at the joint of the upper end of the heat conductor and the boiling pool. The experimental device is resistant to high pressure, good in sealing performance and safety, and capable of achieving boiling heat transfer performance testing and visual shooting of pure refrigerants and refrigerant-lubricating oil mixture pools.

The present invention discloses a microelectronic device temperature control and heat dissipation system based on vapor-liquid phase change nanoemulsion boiling heat transfer, which relates to the field of thermal management technology of microelectronic devices, including a fan radiator, a circulating water pump, a controllable ultrasonic emulsification module and a heat exchanger connected in sequence. The water-cooled heat dissipation system adopts a vapor-liquid phase change nanoemulsion with phase change function (ultrapure water as a continuous phase and a low-boiling organic fluoride as a dispersed phase) as a heat exchange medium, and the configured emulsion is pre-filled into the pipeline of the water-cooled heat dissipation system. The controllable ultrasonic emulsification module is used to perform real-time online regulation of the emulsion parameters to match the heat dissipation requirements of the microelectronic device. By replacing the heat exchange medium of the water-cooled heat dissipation system, the heat dissipation performance is significantly improved compared with single-phase flow heat exchange under the same pump work and the same flow conditions, and the efficient temperature control and heat dissipation requirements of microelectronic devices with a junction temperature not exceeding 85°C are met, and the safe and stable operation of the microelectronic devices under the trend of miniaturization and high integration is guaranteed.

The application provides a cooling method and system for electronic equipment. The method comprises: when the electronic equipment is working, controlling low-boiling cooling medium and high-boiling cooling medium to flow at respective initial mass flow rates; acquiring heat flow density and temperature signals of the electronic equipment in real time, and adjusting the mass flow rates of the low-boiling cooling medium and / or the high-boiling cooling medium in real time. The cooling system comprises an electronic module and a cooling channel, a temperature sensor and a controller located in the electronic module. The cooling channel comprises a first cooling channel and a second cooling channel, and the first cooling channel and the second cooling channel circulate cooling medium with different boiling points. The controller is used for controlling the on-off and mass flow rate of the cooling medium of the first cooling channel, and / or controlling the on-off and mass flow rate of the cooling medium of the second cooling channel. The system and method can solve the problems of instability and low reliability of traditional boiling heat transfer, and can meet the heat dissipation requirements of high heat flow density electronic modules.

The method for analyzing the formation and evolution characteristics of a core melt debris bed based on a particle method mainly comprises the following steps: 1, selecting a particle size to adapt to geometric modeling and coolant modeling; 2, selecting a melt material and a coolant material, setting initial parameters, and starting calculation; 3, calculating melt column fragmentation by using a moving particle semi-implicit method basic model; 4, calculating melt particle solidification and combination by using a melting and solidification model; 5, calculating melt debris collision and settlement to form a debris bed by using a discrete element model; 6, calculating debris bed cooling or remelting by using a decay heat model and a boiling heat transfer model; 7, judging whether the end time is reached, if not, advancing by a time step, and if yes, outputting a calculation result; and the method can predict the melt fragmentation form, debris size distribution, debris bed accumulation form, debris bed coolability and debris bed remelting risk probability after a core melt accident.

A system for transferring heat via pool boiling comprises a pool containing a liquid refrigerant and a component which is partially or fully submerged in the pool. The component has a microstructured surface including cavities having a linear size of at least 5 μm, and the microstructured surface is in contact with the liquid refrigerant. The system exhibits a pool boiling heat transfer coefficient (HTC) of at least 8 kW / m2K for a heat flux in a range from 15-85 kW / m2. In some examples, a refrigerant boiling HTC enhancement ratio of up to 2.5 or higher may be achieved using the component with the microstructured surface, in comparison with a plain (unetched) component.

The utility model discloses a large-temperature-difference high-temperature fused salt and water heat exchange steam production system. The system comprises a fused salt storage tank, a high-pressure hot water storage tank, a fused salt-water / steam heat exchanger and a steam pocket, the fused salt-water / steam heat exchanger is of a multi-shell-pass spiral coil pipe type heat exchanger structure. A plurality of limiting inner barrels are arranged in a shell barrel to form annular cavities of different levels, a plurality of heat transfer pipes are connected in parallel and wound around a central pipe or the wall of an upper-level fiber inner barrel to form spiral coil pipes, and a plurality of sets of spiral coil pipes are arranged in the annular cavities respectively. A shell side fused salt liquid inlet, a shell side fused salt liquid outlet, a pipe side water inlet and a pipe side steam outlet are formed in the shell cylinder body; the fused salt-water / steam heat exchanger is connected with an outlet and an inlet of the fused salt storage tank and further connected with a water outlet and an inlet of the high-pressure hot water storage tank. High-temperature thermal shock damage of the heat exchanger and pipeline blockage caused by fused salt solidification can be effectively eliminated, membrane boiling of water is inhibited, the heat transfer efficiency is high, and system operation is safe and reliable.

This invention discloses a thermosiphon loop device. The evaporator consists of four parts: a liquid chamber, a vapor chamber, a microgroove structure, and a filter screen. The microgroove structure significantly increases the number of vaporization nuclei, enhancing boiling heat transfer. Above the microgroove structure, a hemispherical filter screen is designed to drastically reduce the amount of liquid carried into the vapor chamber, thereby enhancing gas-liquid separation within the evaporator. This gas-liquid separation allows the working fluid to have a higher dryness near the evaporation section outlet, significantly increasing the density difference and pressure driving force between the vapor and liquid phases inside the thermosiphon loop, and improving the heat transfer limit. Furthermore, a heat insulation device is installed in the condensate return pipe at the bottom of the evaporation section to suppress backflow caused by the growth and expansion of boiling bubbles, effectively reducing heat leakage at the bottom of the evaporation section. This invention achieves gas-liquid separation within the evaporator and reduces heat leakage at the bottom, thereby improving the heat transfer performance of the thermosiphon loop and making it suitable for high-power heat dissipation requirements.

The invention discloses a mixed wettability nanowire modified three-stage enhanced boiling heat transfer structure and a preparation method thereof, and belongs to the technical field of micro-nano processing and enhanced phase change heat transfer. According to the structure, two kinds of functional micro-column arrays, namely a micro-cylinder array modified by a super-hydrophilic nanowire and a micro-square column array modified by a super-hydrophobic nanowire, are integrated on a substrate. An efficient liquid supplementing channel is constructed through the strong capillary action, and local dryness is effectively inhibited; the latter is used as a low-superheat-degree nucleation site, rapid generation and separation of bubbles are promoted, bubble coalescence can be effectively inhibited through the millimeter-level spacing, and formation of a steam film is delayed. The two types of micro-columns are orderly distributed in space, and a bubble separation path and a liquid backflow channel are collaboratively optimized. The structure integrates the multi-scale enhanced boiling heat transfer advantages of the millimeter-scale hydrophobic nucleation interval, the micron-scale cylinder and the nano-scale linear structure, the heat transfer coefficient and the critical heat flux are improved, and the structure has important application potential in the high-heat flux heat dissipation fields of high-power electronic devices, aerospace, new energy equipment and the like.

The invention provides a construction method of a nucleation gradient multi-element structure spliced surface based on a femtosecond laser direct writing technology, and relates to the technical field of boiling heat transfer enhanced surface engineering. Femtosecond laser is adopted to conduct cross scanning on a metal substrate to prepare a dot matrix cavity with the automatic liquid supply capacity, and the opening size of the cavity and the bubble production behavior are controlled by adjusting the number of cross lines; preparing a laser-induced periodic structure LIPSS with different roughness on the external surface of the cavity so as to strengthen hydrophilicity; capillary grooves with low nucleation activity are processed in the center of a lattice grid to serve as gap channels, and gas-liquid channel separation and ordered bubble separation are achieved. The surface can cooperatively regulate and control the nucleation density, wettability and gas-liquid separation path, and meanwhile, the boiling heat transfer coefficient and the critical heat flux density are improved.

The application provides an aluminum vapor cavity liquid wick and a preparation method thereof, and relates to the technical field of electronic chip heat dissipation. The preparation method of the aluminum vapor cavity liquid wick comprises the following steps: preparing a porous MAO ceramic film layer on the surface of an aluminum base, significantly increasing the bubble nucleation site density and the corrosion resistance of the aluminum surface; loading FeCo nanoparticles on the surface of the porous MAO ceramic film layer through a self-assembly method, and enhancing the catalytic performance of the surface; and preparing a CNTs coating with a vertical FeCo CNTs array on the surface of the porous MAO ceramic film layer through a chemical vapor deposition method, so that the CNTs coating has the advantages of a high aspect ratio and small pores, the capillary wicking effect is increased, and liquid rewetting is promoted. The aluminum vapor cavity liquid wick with the FeCo CNTs / MAO composite coating on the surface of the aluminum base is prepared, and the composite coating can exert the advantages of the MAO layer and the CNTs coating, and synergistically enhance the heat transfer efficiency and the boiling heat transfer stability of the surface of the aluminum vapor cavity liquid wick.

The application relates to a preparation method of a small-size high-density microchannel, and relates to the technical field of microchannel enhanced phase change heat transfer. One of spin coating, screen printing or spraying is used to coat a photosensitive etching-resistant ink on the surface of a metal base to form a uniform and continuous photosensitive etching-resistant protective coating with a thickness of 0.2-10 microns; a microchannel mask pattern is engraved on the photosensitive etching-resistant protective coating by using a UV laser printer; the metal base with the microchannel mask pattern is soaked in an environment-friendly etching liquid for etching; the target metal base after etching is soaked in a stripping liquid capable of reacting with the photosensitive etching-resistant protective coating, so that the photosensitive etching-resistant protective coating strip is stripped from the surface of the target metal base, the microchannel wall is exposed, and a small-size high-density microchannel structure is obtained. The application has the advantages of accurate size control, good heat transfer performance, high efficiency, strong expansibility, and is especially suitable for the application field of heat dissipation such as enhanced boiling heat transfer.

The present disclosure provides a thin liquid film boiling heat transfer enhancement device, comprising: a vacuum cavity, a first mounting hole is opened in the bottom; an evaporation base is installed in the first mounting hole, and the upper surface of the evaporation base is higher than the inner bottom surface of the vacuum cavity, and the upper surface of the evaporation base is provided with a second mounting hole; a liquid dam is arranged on the upper surface of the evaporation base, a test hole with a predetermined size is arranged at the center of the liquid dam, and the size of the test hole is larger than that of the second mounting hole; an upper heating block is installed in the second mounting hole, and the upper surface of the upper heating block is located in the same horizontal plane as the upper surface of the evaporation base; a lower heating block is arranged in the evaporation base, and the lower heating block is sleeved on the bottom of the upper heating block; a spiral condensing pipe is arranged in the vacuum cavity, and the lower end of the spiral condensing pipe is spaced apart from the upper surface of the evaporation base by a predetermined distance; the centers of the spiral condensing pipe, the evaporation base, the liquid dam, the upper heating block and the lower heating block are located on the same straight line, and the straight line is perpendicular to the horizontal plane.

The present invention discloses a heat pipe-type light steel keel prefabricated building photovoltaic thermal breathing wall system, comprising a heat pipe-type cooling photovoltaic panel layer, a prefabricated light steel keel enclosure structure, and an air interlayer. The heat pipe-type cooling photovoltaic panel layer includes photovoltaic panels and multiple groups of Z-shaped heat pipe heat exchange bundles, each group of which includes a horizontal heat collection copper tube embedded in a thermal insulation material layer and a horizontal heat exchange sleeve arranged in the air interlayer, and the horizontal heat collection copper tube is filled with a low-boiling point working medium. The inner tubes of the horizontal heat exchange sleeves of the multiple groups of Z-shaped heat pipe heat exchange bundles are connected and filled with water. Air vents are provided at the top and bottom of the air interlayer. The present invention can absorb more heat through boiling heat transfer, reduce the temperature of the photovoltaic panel backplane, and improve power generation efficiency. It can also timely condense the gaseous working medium and fully recover heat for the building's domestic hot water supply. It can also improve indoor air quality while reducing the indoor fresh air cooling and heating load.

The invention relates to the technical field of heat dissipation of electronic devices, in particular to a dot matrix type super-hydrophilic-super-hydrophobic mixed wetting surface for strengthening boiling heat transfer and a preparation method of the dot matrix type super-hydrophilic-super-hydrophobic mixed wetting surface. According to the dot matrix type super-hydrophilic-super-hydrophobic mixed wetting surface, a super-hydrophilic surface with a CuO micro-nano sheet thorn structure is constructed and formed on the surface of a copper substrate through a chemical oxidation method, and a super-hydrophobic dot matrix surface is prepared on the super-hydrophilic surface by spraying a super-hydrophobic coating and used for increasing bubble nucleation sites and accelerating supply of liquid to the bubble nucleation sites, so that the number of bubble nucleation sites is increased. Bubble combination is inhibited; the super-hydrophobic dot matrix surface is obtained by discretely arranging hexagonal dot matrix units; the contact angle of the surface of the super-hydrophobic dot matrix is not less than 160 degrees; and the contact angle of the super-hydrophilic surface is 0-10 degrees. Hexagonal dot matrix units are discretely distributed on a super-hydrophilic surface of a CuO micro-nano sheet thorn structure to form a super-hydrophobic dot matrix surface; the technical problem that the boiling heat transfer coefficient and the critical heat flux of an existing boiling heat transfer surface are difficult to consider at the same time is solved.

The present invention provides a boiling heat transfer surface for a boiling cooler and a method for forming the same, which can improve cooling performance by quickly removing large bubbles from the heat transfer surface so that they do not become covered on the boiling heat transfer surface. [Solution] The boiling heat transfer surface of the boiling cooler receives heat from an external heating element and boils the internal liquid-phase coolant, causing it to change from liquid to vapor. The boiling heat transfer surface 1 is formed by bending the tip ends of a plurality of plate-shaped fins 3 that are formed standing upright in parallel at a predetermined distance from a metal substrate 2 and joining them to adjacent fins 3 to form cavities 4 between the fins 3. A plurality of small holes 5 are formed at predetermined distances from the upper end of adjacent cavities 4. The inner wall 3a on one side and the inner wall 3b on the other side of the cavity 4 are inclined toward the other side of the metal substrate 2, and the bottom surface 4a is formed as an inclined surface that gets higher from one side to the other. The small holes 5 are formed by grooves 51 formed on the tip side of the fins 3, and the tip side of the fins 3 is bent from a virtual bending line BL that connects the bottoms 51a of the plurality of grooves 51.

The invention provides a non-uniform structured material for strengthening boiling heat transfer and a preparation method of the non-uniform structured material, and belongs to the technical field of strengthening phase change heat transfer. The millimeter-level porous column comprises a first stepped porous coating layer, the porosity of the first stepped porous coating layer is gradually increased from bottom to top, and a super-hydrophobic coating layer is locally arranged at the top of the first stepped porous coating layer; the mini-porous column comprises a second stepped porous coating, the porosity of the second stepped porous coating is gradually increased from bottom to top, and the top of the second stepped porous coating is subjected to super-hydrophilic treatment; and gaps between the millimeter-scale porous columns and the mini-porous columns form channels. The number of gasification cores of the non-uniform structured material is effectively increased, the superheat degree of the surface is reduced, and therefore the boiling heat transfer coefficient of the surface under the low heat flux density is increased.

The utility model discloses a kind of heat exchange tube and reboiler, the heat exchange tube includes tube body and heat transfer layer, the heat transfer layer is located at the inner surface or outer surface of the tube body, the heat transfer layer is equipped with multiple helical grooves and helical protruding parts of alternate arrangement, each the helical protruding part is equipped with groove group on. The utility model its structure can effectively increase heat exchange area and enhance heat exchange effect. Meanwhile, the three-dimensional porous structure of the utility model significantly enhances boiling heat transfer, wherein the heat transfer layer includes multiple helical grooves and helical protruding parts of alternate arrangement, the groove group cooperation on the surface of the helical groove and the helical protruding part makes the rotating flow of the medium to be heated when flowing, enhances turbulence degree, realizes the promotion of heat transfer efficiency.

A phase change steam generator relates to a high-temperature heating heat exchange technology, solves the technical defects that a tubular heat exchanger and a plate heat exchanger are low in heat exchange efficiency, can bring out water vapor and cannot meet the clean fresh steam requirement, and comprises a barrel, a heat exchange tube and a gas-liquid separation bag, the gas-liquid separation bag is arranged above the cylinder body, the lower part of the gas-liquid separation bag is connected with an automatic drain valve, drain water at the outlet end of the automatic drain valve is connected to the cylinder body through a water return pipe, and the cylinder body and the gas-liquid separation bag are also provided with a steam pipeline; a steam-water separation partition plate is arranged in the gas-liquid separation bag, and a steam outlet is formed in the position, above the steam-water separation partition plate, of the gas-liquid separation bag. According to the invention, boiling heat transfer and vapor-liquid separation can be simultaneously carried out for direct recycling; separated water can be fully refluxed for use; bubble condensation is avoided, the influence of bag-shaped bubbles on heat transfer is reduced, and meanwhile boiling heat transfer and vapor-liquid separation are efficiently achieved.

A valve-free countercurrent detonation shock wave reactor utilizes a static mechanical structure to automatically generate periodic countercurrent detonation shock waves. The generated detonation shock waves are controllable and adjustable in terms of high temperature, high pressure, and high speed. The present invention utilizes the thermodynamic characteristics of detonation shock waves and can generate stable and controllable detonation shock waves without the need for precise valve control and ignition timing control, thereby resolving the bottleneck in the development of high-speed shock wave engine technology used in high-speed aircraft. Another application is to remove the hazards of flammable and explosive gases and safely handle the high-concentration VOCs waste gas treatment problem that has remained unsolved for a century in the petrochemical and chemical industries. The main structure of the countercurrent detonation shock wave reactor without valve control includes: a group of detonation shock wave reactor tubes containing detonation accelerators, which are composed of a plurality of serially connected reduced diameter pipe sections, expanded diameter pipe sections and straight pipe sections; a boiling heat transfer enhancement structure is provided on the outer surface of the detonation shock wave reactor tube; multiple gas reactant dispersion feed pipes that can provide gas mixing and terminate the countercurrent detonation shock wave extend into the detonation reactor tube; an anti-detonation flame arrester; multiple sets of ignition devices are installed in the straight pipe section of the detonation shock wave reactor tube; a detonation wave exhaust pipe and a secondary vortex air jacket are installed downstream of the straight pipe section of the detonation shock wave reactor tube.

The application provides a kind of multi-physical field coupling core particle micro-channel boiling heat transfer experimental testing device and testing method, belongs to the field of boiling heat transfer experimental testing device.The application innovatively integrates laser heat control module, reflective temperature measurement module, particle velocity measurement module, three-dimensional micro-control module, stress test module, sound field test module and electric field test module, and realizes flexible combination and active control of each physical field through standardized interface.Pulse laser is used to realize local point heating, thermal reflection method is used to realize non-contact transient surface temperature analysis, PIV system is used to analyze micro-nano scale phase change flow field, and embedded thin film strain gauge group is used to measure local thermal stress, and high-precision piezoelectric displacement table is used to realize automatic alignment and collaborative measurement of each module.Through modular design and system integration, precise coupling and collaborative measurement of light, sound, heat, force and flow multi-physical fields on the core particle scale are realized.