16130results about "Heat-exchange elements" patented technology

The present invention relates to compositions for use in refrigeration, air-conditioning, and heat pump systems wherein the composition comprises a fluoroolefin and at least one other component. The compositions of the present invention are useful in processes for producing cooling or heat, as heat transfer fluids, foam blowing agents, aerosol propellants, and fire suppression and fire extinguishing agents.

A non-combustion, chemical heat source includes a heat chamber having a closed end and an open end. The heat chamber includes an apertured heat cartridge disposed at the open end of the chamber, an abutment disposed at the closed end of the chamber, an activating solution, a frangible seal separating the activating solution and the heat cartridge. The heat cartridge includes metallic agents that may come in a variety of configurations. The heat source is activated when the heat cartridge is pushed through and breaks the frangible seal allowing contact between the metallic agents and the activating solution. The heat cartridge includes an aperture in the bottom of the cartridge and absorbent paper surrounding the metallic agents, both of which control the transfer of the activating solution into the metallic agents to cause the chemical reaction. The heat sources may be incorporated into smoking articles and may also be used to heat foods or beverages, in hand warmers, and to heat equipment or materials.

Disclosed herein are processes for the production of hydrofluoroolefins by dehydrofluorination. Also disclosed herein are processes for separation of hydrofluoroolefins from hydrofluorocarbons and from hydrogen fluoride.

A non-combustion, chemical heat source includes a heat chamber having a closed end and an open end. The heat chamber includes an apertured heat cartridge disposed at the open end of the chamber, an abutment disposed at the closed end of the chamber, an activating solution, a frangible seal separating the activating solution and the heat cartridge. The heat cartridge includes metallic agents that may come in a variety of configurations. The heat source is activated when the heat cartridge is pushed through and breaks the frangible seal allowing contact between the metallic agents and the activating solution. The heat cartridge includes an aperture in the bottom of the cartridge and absorbent paper surrounding the metallic agents, both of which control the transfer of the activating solution into the metallic agents to cause the chemical reaction. The heat sources may be incorporated into smoking articles and may also be used to heat foods or beverages, in hand warmers, and to heat equipment or materials.

The present invention relates to fluoroolefin compositions. The fluoroolefin compositions of the present invention are useful as refrigerants or heat transfer fluids and in processes for producing cooling or heat. Additionally, the fluoroolefin compositions of the present invention may be used to replace currently used refrigerant or heat transfer fluid compositions that have higher global warming potential.

The present invention relates to compositions for use in refrigeration, air-conditioning, and heat pump systems wherein the composition comprises a fluoroolefin and at least one other component. The compositions of the present invention are useful in processes for producing cooling or heat, as heat transfer fluids, foam blowing agents, aerosol propellants, and fire suppression and fire extinguishing agents.

Nano-composite materials with enhanced thermal performance that can be used for thermal management in a wide range of applications, including heat sinks, device packaging, semiconductor device layers, printed circuit boards and other components of electronic, optical and / or mechanical systems. One type of nano-composite material has a base material and nanostructures (e.g., nanotubes) dispersed in the base material. Another type of nano-composite material has layers of a base material with nanotube films disposed thereon.

A thermally-conductive interface for conductively cooling a heat-generating electronic component having an associated thermal dissipation member such as a heat sink. The interface is formed as a self-supporting layer of a thermally-conductive material which is form-stable at normal room temperature in a first phase and substantially conformable in a second phase to the interface surfaces of the electronic component and thermal dissipation member. The material has a transition temperature from the first phase to the second phase which is within the operating temperature range of the electronic component.

Disclosed is a method for detecting a leak in a closed loop heat transfer system comprising monitoring the pressure of the heat transfer composition inside said heat transfer system, wherein a drop in pressure indicates a leak. Also disclosed is a heat transfer system comprising an evaporator, a compressor, a condenser, an expander and a device for measuring internal system pressure. The system pressure measuring device is disposed inside the closed loop heat system. The internal system pressure measuring means may be located either between the evaporator and the condenser, between the expander and the evaporator, between the compressor and the condenser, or between the condenser and the expander.

The invention relates to a preparation method of a polymer / graphene composite material through in situ reduction, which is characterized by comprising the following steps: adopting ultrasonic wave or grinding to evenly disperse the graphite oxide prepared by a Hummers method into polymer dispersion; introducing reducing agent into the polymer dispersion for in situ reduction, enabling the graphite oxide to be reduced into the grapheme so as to obtain stable polymer / graphene composite emulsion; carrying out demulsification, agglomeration and drying to obtain the composite polymer / grapheme composite master batch; adding the dried polymer / grapheme composite master batch and various assistants into the polymeric matrix according to a certain ratio; and carrying out double-roller mixing, vulcanization, melt extrusion or injection molding to obtain the polymer / graphene composite material with excellent physical and mechanical properties.

The present invention relates to compositions for use in refrigeration, air-conditioning, and heat pump systems wherein the composition comprises a tetrafluoropropene and at least one other component. The compositions of the present invention are useful in processes for producing cooling or heat, as heat transfer fluids, foam blowing agents, aerosol propellants, and fire suppression and fire extinguishing agents.

A process for recovering waste heat which comprises: (a) passing a liquid phase working fluid through a heat exchanger in communication with a process which produces the waste heat; (b) removing a vapor phase working fluid from the heat exchanger; (c) passing the vapor phase working fluid to an expander, wherein the waste heat is converted into mechanical energy; and (d) passing the vapor phase working fluid from the expander to a condenser, wherein the vapor phase working fluid is condensed to the liquid phase working fluid. The preferred working fluid is an organic Rankine cycle system working fluid comprising compounds having the following general structure: where x, y, z, and m are each selected from the group consisting of: fluorine, hydrogen, Rf, and R, wherein R and Rf are each an alkyl, aryl, or alkylaryl of 1 to 6 carbon atoms, and wherein Rf is partially or fully fluorinated.

Provided are azeotrope-like compositions comprising pentafluoropropene (HFO-1225) and a fluid selected from the group consisting of 3,3,3-trifluoropropene (“HFO-1243zf”), 1,1-difluoroethane (“HFC-152a”), trans-1,3,3,3-tetrafluoropropene (“HFO-1234ze”), and combinations of two or more thereof. Also provided are uses thereof including as refrigerants, blowing agents, sprayable compositions, flame suppressant, and the like.

Disclosed are compositions comprising at least one iodocarbon compound and preferably at least one stabilization agent comprising a diene-based compound. These compositions are generally useful as refrigerants for heating and cooling, as blowing agents, as aerosol propellants, as solvent composition, and as fire extinguishing and suppressing agents.

Disclosed are compositions useful in a wide variety of applications, including heat transfer fluids which possess a highly desirable and unexpectedly superior combination of properties, and heat transfer systems and methods based on these fluids. The preferred heat transfer fluid comprises from about 1 to about 40 percent, on a weight basis, of carbon dioxide (CO2) and from about 99 to about 60 percent, on a weight basis, of a compound having the Formula I XCFzR3-z (I), where X is a C2 or a C3 unsaturated, substituted or unsubstituted, alkyl radical, each R is independently Cl, F, Br, I or H, and z is 1 to 3. A preferred compound of Formula I is tetrafluoropropene, particularly 1,1,1,3-tetrafluoropropene and / or 1,1,1,3-tetrafluoropropene.

The use to e of tetrafluoropropenes, particularly (HFO-1234) in a variety of applications, including refrigeration equipment, is disclosed. These materials are generally useful as refrigerants for heating and cooling, as blowing agents, as aerosol propellants, as solvent composition, and as fire extinguishing and suppressing agents.

A novel fluid heat transfer agent suitable for use in a closed heat transfer system, for example, wherein energy is transferred between an evaporator and a condenser in heat exchange relationship with the heat transfer agent that is caused to flow from one to the other. The novel heat transfer agent is a complex comprising a body of heat transfer fluid, for example, ethylene glycol or water, having suspended therein carbon nanoparticles in a quantity sufficient to enhance the thermal conductivity of the body of heat transfers fluid, per se. The carbon nanoparticles are selected from carbon in the form of sp<2 >type and sp<3 >type bonding and preferably comprise nanotubes or fullerenes and may have a coupling agent bonded thereto or enclosed therein when the nanotube or fullerene forms a hollow capsule. The coupling agent may be a polar organic group covalently bonded to the carbon nanoparticles and miscible in the fluid medium.

A method for providing refrigeration such as to an insulated enclosure wherein a defined multicomponent refrigerant fluid undergoes a phase change coupled with Joule-Thomson expansion to generate refrigeration over a wide temperature range which may comprise from ambient to low temperatures.

The present invention relates to heat transfer compositions comprising 2,3,3,3-tetrafluoropropene, difluoromethane, pentafluoroethane, and 1,1,1,2-tetrafluoroethane for use in refrigeration, air-conditioning, heat pump systems, and other heat transfer applications. The inventive heat transfer compositions can possess reduced global warming potential while providing good capacity and performance.

A low-melting point, heat transfer fluid made of a mixture of four inorganic nitrate salts: 9-18 wt % NaNO3, 40-52 wt % KNO3, 13-21 wt % LiNO3, and 20-27 wt % Ca(NO3)2. These compositions can have liquidus temperatures less than 100 C; thermal stability limits greater than 500 C; and viscosity in the range of 5-6 cP at 300 C; and 2-3 cP at 400 C.

A thermal interface material (40) includes a macromolecular material (32), and a plurality of carbon nanotubes (22) embedded in the macromolecular material uniformly. The thermal interface material includes a first surface (42) and an opposite second surface (44). Each carbon nanotube is open at both ends thereof, and extends from the first surface to the second surface of the thermal interface material. A method for manufacturing the thermal interface material includes the steps of: (a) forming an array of carbon nanotubes on a substrate; (b) submerging the carbon nanotubes in a liquid macromolecular material; (c) solidifying the liquid macromolecular material; and (d) cutting the solidified liquid macromolecular material to obtain the thermal interface material with the carbon nanotubes secured therein.

Thermal interface compositions contain both non-electrically conductive micron-sized fillers and electrically conductive nanoparticles blended with a polymer matrix. Such compositions increase the bulk thermal conductivity of the polymer composites as well as decrease thermal interfacial resistances that exist between thermal interface materials and the corresponding mating surfaces. Such compositions are electrically non-conductive. Formulations containing nanoparticles also show less phase separation of micron-sized particles than formulations without nanoparticles.

The invention discloses a heat conductive silicone grease composition which mainly contains a carbon nano tube, graphite, phase-change capsule particles and silicone oil, wherein the carbon nano tube can speed up the conduction of heat further; the phase-change capsule particles are used for improving the initial temperature absorption velocity of a heat end; the phase-change capsule particles, the carbon nano tube and graphite in a fluid form full-three-dimensional network distribution of particles (phase-change capsule), a line ( the carbon nano tube) and a plane (graphite) in the fluid finally. The heat conductive silicone grease composition provided by the invention has high heat conduction rate and low heat resistivity, the heat radiation efficiency of the heat conductive silicone grease is improved greatly, the service life of the heat conductive silicone grease is prolonged greatly, and the heat conductive silicone grease composition has high practical value.

The present invention relates to compositions for use in refrigeration, air-conditioning, and heat pump systems wherein the composition comprises E-1,2-difluoroethylene. The compositions of the present invention are useful in processes for producing cooling or heat, as heat transfer fluids, foam blowing agents, aerosol propellants, and power cycle working fluids.

Compositions and methods based on the use of fluoroalkene containing from 3 to 4 carbon atoms and at least one carbon-carbon double bond, such as HFO-1214, HFO-HFO-1233, or HFO-1354, having properties highly beneficial in solvent cleaning applications.

To provide a working medium for heat cycle, of which combustibility is suppressed, which has less influence over the ozone layer, which has less influence over global warming and which provides a heat cycle system excellent in the cycle performance (capacity), and a heat cycle system, of which the safety is secured, and which is excellent in the cycle performance (capacity).A working medium for heat cycle comprising 1,1,2-trifluoroethylene is employed for a heat cycle system (such as a Rankine cycle system, a heat pump cycle system, a refrigerating cycle system 10 or a heat transport system).

A fireproof insulating foamed cementitious composition with thermal energy storage capacity is provided for use in producing wall insulation boards, fireproof claddings for steel structures, inner cores of fire resistant wall or door panels, and the like. The composition demonstrates improved energy efficiency in which phase change materials, such as microencapsulates, are used in conjunction with a cementitious mixture of calcined gypsum and hydraulic cement, lightweight aggregates, a polymer latex, and a foaming solution to create stable air bubbles inside the cementitious matrix. The calcined gypsum and the hydraulic cement are present in a weight ratio range from about 1:3 to about 3:1. The composition may further include reinforced fibers, surfactants, inorganic flame retardants, and other additives. The presence of the phase change material not only increases energy efficiency of the cured cementitious foam material, but also improves compatibility between calcined gypsum and cement during slurry mixing and hardening.

A portable heat source that may be used to warm food, beverage or other supplies. The heater contains a heat-producing composition that is a solid that may be stored for long periods of time, and activated by addition of water or an aqueous solution. Heat-producing compositions contain an acidic anhydride, an acidic salt, a basic anhydride or a basic salt. Preferred heat-producing compositions contain a mixture of an acidic anhydride or salt together with a basic anhydride or salt, such that addition of water to both acidic and basic anhydrides produces heat as well as acid and base respectively; subsequent reaction of the acid and base produces additional heat, as well as a safe, neutral product that is easily disposed. The invention further consists of means and methods for regulating the rate of heat production in heaters by the addition of inert additives to heat-producing compositions and the application of processing methods that regulate access of water to heat-producing compounds. Addition of inert materials and shaping, agglomerating, pelleting and like processing of heat-producing materials are applied to produced heat at a rate compatible with the rate at which the food or other materials can absorb the heat. The invention further consists of devices incorporating the materials to be heated in an advantageous arrangement with the heater composition.