52results about How to "Enhanced boiling heat transfer" patented technology

The invention relates to a high-efficiency gravity heat pipe and a manufacturing method thereof. The high-efficiency gravity heat pipe comprises an evaporating section, a heat insulating section and a condensing section, and is characterized in that a metal powder porous layer is sintered on the inner surface of the heat tube evaporating section, and the condensing section is chemically coated. The heat tube manufactured by the process method in the invention can simultaneously reinforce boiling heat transfer and condensing heat transfer, so that a plurality of ideal vaporization cores are artificially increased, thus the boiling phenomenon of the liquid is continuously carried out to achieve a purpose of reinforcing the boiling heat transfer; on the other hand, the surface of a chemical coating of the heat tube condensing section is modified to acquire a low surface free energy value; simultaneously, the coating layer is a metal-based coating layer with good thermal conductivity, thus the condensing heat transfer can be reinforced; from the above, the high-efficiency gravity heat tube reinforce the boiling and condensing effects very remarkably, has the characteristics of good heat transfer reinforcing effect, high production efficiency, low cost and the like.

The invention relates to a system capable of conducting power recovering and cooling by using waste heat of blast furnace slag flushing water, and belongs to the technical field of energy and environment. The system comprises a slag flushing water heat recovery and heat exchange system, an organic Rankine cycle, a steam injection type cooling system and a cooling water circulation system. An internal-thread stainless steel spiral tube shell-and-tube heat exchanger is used as a pre-heater, an external-thread stainless steel tube shell-and-tube heat exchanger is used as a steam generator, and the steam generator is also used as a gas-liquid separator. The system has the advantages of being simple in structure, easy to machine and manufacture, low in manufacturing cost, capable of preventing blockage, capable of realizing countercurrent flow heat exchange, high in heat exchange efficiency, capable of effectively utilizing waste heat of the slag flushing water and the like; the system can be independently used for generating electricity or providing prime power, can also be independently used for cooling and can further provide electric power and chilled water required by a cooling air conditioner at the same time.

The present disclosure provides, among other things, scale-coated surfaces, vessels with controlled deposits of scale, and associated methods for enhanced boiling heat transfer. It is presently found that creating and/or maintaining a scale deposit at a controlled thickness actually enhances a type of boiling called nucleate boiling, which improves heat transfer.

The invention discloses a nanometer copper material capable of transferring heat with high efficiency, and a preparation method thereof. The surface of the nanometer copper material is coated with an ultra-thin nano or micro-nano composite porous nickel film with super wetting ability; the ultra-thin nano composite porous nickel film comprises a porous structure which is mainly made of nickel nano flowers; and the ultra-thin micro-nano composite porous nickel film comprises a porous structure which is mainly formed by accumulation of micron or nanometer nickel triangular sheets. The preparation method comprises following steps: a substrate is taken as working electrode; the working electrode, a counter electrode and a reference electrode are placed in a weak acid nickel salt electrolyte so as to form a reduction system; reduction current is provided between the working electrode and the counter electrode so as to realized nickel electro-deposition on the surface of the substrate; and then the ultra-thin nano or micro-nano composite porous nickel film is formed on the surface of the substrate. The ultra-thin nano or micro-nano composite porous nickel film is capable of increasing utilization stability of the nanometer copper material, and improving filmwise condensation heat transfer performance, boiling heat transfer performance and spray cooling heat dissipation performance of the nanometer copper material greatly. The formula of the electrode needed in the preparation method is simple; raw material are cheap and easily available; optional range of electroplating mode is wide; and the preparation method is suitable for industrialized large-scaled application.

The invention belongs to the technical field of heat transmission, and relates to a heat exchange plate, in particular to a heat exchange plate for a plate-type evaporator. On the basis of a heat exchange plate substrate, the upper end face of the heat exchange plate substrate is provided with micro ribs and micro grooves, and alternatively, the surface of the heat exchange plate substrate is provided with rough structures. The heat exchange plate has the advantages that multiple rough surfaces can increase vaporization core number, reduce the degree of superheat of the wall surface, strengthen boiling heat transfer, and further improve the total heat transfer coefficient of the evaporator.

An apparatus and a method of enhancing boiling heat transfer therein capable of increasing both the critical heat flux and nucleate boiling heat transfer of a working fluid. The method includes placing free particles on a surface so as to define narrow corner gaps and cavities at interfaces between the particles and the surface and heating the surface while the surface is contacted by the working fluid to bring the working fluid to a boil, with the result that bubble nucleation is facilitated and nucleate boiling heat transfer from the surface is increased.

The invention discloses a surface preparation method capable of preparing various nanowire structures, and belongs to the technical field of surface treatment. According to the method, by means of a template-assisted electroplating method, various structural appearances such as an upright type, an agglomeration type and a round pit type can be formed by changing the interval and aperture of template holes and the electroplating time, and the structure height and included angle of the upright type and the agglomeration type can be changed. Nanowires are 4-50 microns high, the center distance ofthe nanowires is 60-500 nm, and the diameter of the nanowires is 5-400 nm. The surface appearances prepared through the preparation method are controllable, the structural form is diversified and cross-scale, the upright type and the agglomeration type can be used for condensation, and the round pit type can be applied to the field of phase-change heat transfer such as boiling.

The invention discloses a loop heat pipe with a multi-scale structure synergistic mixed wettability inner surface. All parts are sequentially connected in series to form a cycle, the interior of the loop heat pipe is provided with the multi-scale structure synergistic mixed wettability inner surface, and the loop heat pipe comprises an evaporator, a condenser, a steam line and a liquid line, and the evaporator is provided with a multi-scale capillary core with gradient hydrophilicity and hydrophobicity. The size is gradually reduced in the circulation direction, the surface is transited from hydrophobicity to hydrophilicity, hydrophobic points are arranged in a hydrophilic area, and hydrophilic points are arranged in a hydrophobic area. The condenser is provided with a multi-scale micro-column inner surface with gradient hydrophobicity, the surface of a nanoneedle transits from super hydrophobicity to hydrophobicity in the circulation direction, and the top end of the embedded micro-column is hydrophilic and forms a hydrophilic point. The steam line and the liquid line are reducing pipes, the pipe diameter and the size of the porous structure on the inner surface are gradually reduced in the circulation direction, and gradient wettability is achieved. By means of the reasonably-designed cooperation mode of the surface multi-scale structure and the mixed wettability, the requirements of different areas and stages of the loop heat pipe for the structure scale and wettability can be met, and the heat exchange performance of the loop heat pipe is improved through all-around cooperation.

The invention discloses a sound field enhanced nanofluid phase change heat transfer micro-channel heat exchanger. The micro-channel heat exchanger comprises a heat exchanger substrate internally provided with a rectangular groove, a micro-channel base plate arranged in the rectangular groove of the heat exchanger substrate, and a cover plate covering an opening of the rectangular groove of the heat exchanger substrate in a sealed mode through several bolts. Two ends of the heat exchanger substrate are provided with an inlet joint and an outlet joint of inflow and outflow nanofluids. The heat exchanger also comprises at least one ultrasonic transducer component whose pitching angle is adjustably and fixedly arranged in the rectangular groove of the heat exchanger substrate. In the invention, an application of ultrasonic enhanced heat transfer technology to the micro-channel heat exchanger is achieved, an ultrasonic transducer is arranged in heat exchanger and can directly act on a heatexchange working medium, growth and separation of boiling bubbles are promoted, and heat transfer performance of the micro-channel heat exchanger is increased by above 20% in combination with a nanofluid enhanced heat transfer technology compared with that of a common micro-channel heat exchanger.