286 results about "Double walled" patented technology

The invention provides a method for preparing a carbon nanotube with assistance of carbon dioxide, which is characterized in that methane is used as a carbon source, carbon dioxide is used as auxiliary gas, and the carbon nanotube is prepared under the action of a catalyst. Carbon deposition generated by using methane as carbon source gas is reduced by using carbon dioxide, and the quality and performance of single-wall, double-wall or three-wall carbon nanotubes are improved, so that application requirements are met.

The present invention discloses a sealing detection device and a detection method for a jet component of a dual-fuel engine. The device includes an upper sealing cover plate, a side test cover plate, and a lower sealing cover plate. The upper sealing cover plate includes an upper cover plate, a connecting pipe, and a ball valve. The rabbet of the upper cover plate is embedded between the inner sleeve and the outer pipe in the upper interface of the double-wall connecting pipe. O-ring seals are respectively arranged on the inner sleeve and the outer pipe, and the upper cover plate is fixed on the upper interface of the double-wall connecting pipe. The side test cover plate is fixed on the side interface of the double-wall connecting pipe. The double-wall connecting pipe and the pipe seat are fixedly connected into one body, and the lower sealing cover plate is hermetically fixed on the lower interface of the pipe seat. The method includes: 1) completing the installation of the sealing detection device; 2) hoisting the jet component into water to detect whether there is leakage. The present invention can accurately detect whether the jet component leaks with only one pressurization test on the jet component. It is fast, efficient, and the detection result is reliable, significantly shortening the detection time, reducing the detection cost, and remarkably improving the detection efficiency and detection quality.

The invention relates to an external cylinder cover air inlet channel methanol injection switching system, and relates to the field of ship engineering and power systems. The methanol spraying device comprises a cylinder cover, a front-end switching block arranged at one end of the top of the cylinder cover, a methanol spraying device penetrating through the front-end switching block, a middle-end switching block arranged at the top of the methanol spraying device and connected with the front-end switching block, a rear-end switching block arranged on the middle-end switching block, a methanol distribution block arranged on the rear-end switching block and a methanol double-wall pipe arranged on the methanol distribution block. The alcohol spraying device is obliquely arranged above the air inlet channel and follows the air inlet direction, so that the spraying resistance is reduced; the methanol double-wall pipe is connected to the two transverse sides of the methanol distribution block, and methanol is supplied to the methanol sprayer through the middle-end adapter block and the rear-end adapter block. The external connection type design is adopted, large-scale transformation of an existing engine structure is not needed, the transformation cost and the implementation difficulty are reduced, and the method is suitable for various types of ship engines.

The invention discloses a gas lift reverse circulation drilling starting pressure and circulation gas supply pressure calculation method. The method comprises the following steps that S1, hydrostatic pressure of the bottom of an inner pipe of a double-wall drill rod is calculated; s2, calculating the friction loss pressure of compressed air of an outer annulus of the double-wall drill rod; s3, calculating the friction loss pressure of the compressed air flowing through the earth surface gas transmission channel; s4, calculating the local pressure loss of the compressed air passing through the orifice in the gas-liquid mixer from the outer pipe of the double-wall drill rod; s5, calculating the liquid phase flow friction pressure loss of the inner pipe of the double-wall drill pipe; s6, calculating the liquid-phase flow friction pressure loss of the deslagging pipeline; s7, calculating the three-phase flow pressure drop of the inner pipe of the double-wall drill pipe; and S8, the starting pressure and the circulating air supply pressure are calculated. According to the method for calculating the starting pressure and the circulating gas supply pressure of the gas lift reverse circulation drilling, the starting pressure and the circulating gas supply pressure of the gas lift reverse circulation drilling can be accurately and conveniently calculated by accurately calculating the pressure of each part of the gas lift reverse circulation drilling process, and a theoretical basis is provided for stable and efficient operation of a circulating system.

The invention relates to a tail gas denitration system and method for an ammonia fuel ship, an ammonia supply pipeline of an ammonia fuel engine in the system adopts a double-wall pipe, the inner pipe of the double-wall pipe is used for conveying liquid ammonia, and the outer pipe of the double-wall pipe is connected with an ammonia treatment system through a fan so as to suck leaked ammonia gas to the ammonia treatment system; the ammonia treatment system is connected with the buffer tank through a fan and is used for conveying the discharged gas to the buffer tank after pressurizing the discharged gas through the fan; the ammonia treatment system is connected with a reducing agent tank through a pump; the reducing agent tank receives ammonia water of the ammonia treatment system through the pump; the SCR reducing agent supply system is connected with the reducing agent spray gun through the reducing agent tank and the buffer tank and used for conveying the discharged gas to the reducing agent spray gun through the SCR reducing agent supply system to assist in atomizing ammonia water. According to the ammonia fuel ship tail gas denitration system and method, ammonia water generated in the ammonia treatment system is used as a reducing agent of the SCR system, and discharged gas of the ammonia treatment system is used as auxiliary atomization gas of the reducing agent, so that waste is recycled, and the denitration efficiency is improved.

The invention discloses a high-thermal-conductivity polypropylene composite material and a preparation method thereof, and belongs to the technical field of high polymer material modification. The high-thermal-conductivity polypropylene composite material comprises the following components in parts by mass: 70-80 parts of polypropylene resin; 20 to 30 parts of graphene oxide; 0.1 to 0.5 part of a double-walled carbon nanotube; 5 parts of maleic anhydride grafted polypropylene; and 1 part of an auxiliary agent. Wherein the adopted graphene oxide has a two-position structure, the double-walled carbon nanotube has a one-dimensional structure, and both the graphene oxide and the double-walled carbon nanotube have very high heat conductivity coefficients; when the two materials are added into polypropylene at the same time, the micro-content of the double-walled carbon nanotube with the one-dimensional structure plays a role in lapping in the melt blending process, and forms a network structure together with the graphene oxide with the two-dimensional structure, so that the heat-conducting property of the polypropylene composite material is greatly improved.

A combustor panel (200) is disclosed herein. The combustor panel (200) includes a top side, a bottom side opposite the top side, a feature (202) coupled to the top side and extending orthogonally away from the top side, the feature (202) defining a first space on the bottom side beneath the feature (202), a first plurality of cooling holes (204) extending in a first direction from the top side to the bottom side, a second plurality of cooling holes (206) extending in a second direction from the top side to the bottom side, the second direction being rotated about 1 ° to about 60° counter-clockwise from the first direction, and a third plurality of cooling holes (206) extending in a third direction from the top side to the bottom side, the third direction being about rotated 1° to about 60° clockwise from the first direction.

The invention relates to a double-wall storage tank. The double-wall storage tank comprises an inner container surrounded by an outer sheath. More specifically, the present invention relates to a double-walled storage tank comprising an arrangement for coupling an inner container relative to an outer jacket.

The invention discloses a diesel engine methanol injection system with an airtight detection function, which is formed by communicating a methanol liquid inlet double-wall pipe, a methanol liquid return double-wall pipe, a methanol pressurizing unit and a high-pressure pipeline, the methanol liquid inlet double-wall pipe is communicated with a fresh water supply system through a liquid inlet stop valve, and the methanol liquid return double-wall pipe is provided with a liquid return stop valve; a liquid return chain pipe valve is communicated between the methanol liquid return double-wall pipe and the methanol pressurizing unit, and a communication valve is arranged between the methanol liquid inlet double-wall pipe and the methanol liquid return double-wall pipe; a communicating port of the high-pressure pipeline and the methanol pressurizing unit is plugged through a plugging tool which is detachably arranged on the methanol pressurizing unit, and a plurality of methanol pressure detection sensors are arranged on the methanol liquid inlet double-wall pipe and the methanol liquid return double-wall pipe respectively. According to the airtightness detection method for the marine methanol low-speed diesel engine, fresh water which has intersolubility with methanol is used as a tightness detection medium, complete tightness detection of a methanol spraying system of the marine methanol dual-fuel low-speed diesel engine is achieved, the detection efficiency is high, and the leakage point detection speed is high.

The invention relates to the technical field of gas engines, and particularly discloses an anti-deformation and high-cooling-efficiency backflow combustion chamber large elbow, the sections of a first layer wall and a second layer wall of the large elbow are arc-shaped, the first layer wall is arranged outside the second layer wall, one end of the first layer wall and one end of the second layer wall are fixedly connected into a whole, and the other end of the first layer wall is arranged outside the second layer wall. The other end of the first layer wall and the other end of the second layer wall are clamped, a space capable of moving relative to each other is formed in the clamping position, a plurality of annular grooves facing the second layer wall are formed in the first layer wall, the annular grooves are attached to the side, facing the first layer wall, of the second layer wall, and a cavity between the first layer wall and the second layer wall is divided into a plurality of impact diffusion cavities through the annular grooves. According to the invention, the gap between the double walls is not changed, the problem of deformation caused by stress due to inconsistent swell capacity of the double walls is prevented, the cooling protection effect of the inner wall is enhanced, cracks caused by too high temperature of the large elbow are prevented, the overall stress is small, cracks are not easy to appear at welding joints, tight connection is realized, and air leakage is not easy.

A method and system for Direct Electrical Heating of a Pipe-In-Pipe pipeline for transporting fluids includes mechanically connecting the steel inner shell to the steel outer shell at different intervals of the pipeline, establishing an electrical and thermal insulation between the inner shell and the outer shell, applying an alternating electric current between an outer surface of the inner shell and an inner surface of the outer shell over the entire length of the pipeline so as to heat the inner shell of the pipeline by Joule effect, and placing on the outer surface of the inner shell at least one layer made of resistive and ferromagnetic material so as to increase the ratio of electric power transmitted to the inner shell.

The invention discloses a gas combustion device double-wall exhaust pipe and an LNG marine gas combustion device.The gas combustion device comprises an exhaust pipe inner pipe and an exhaust pipe outer pipe, the exhaust pipe inner pipe is arranged in the exhaust pipe outer pipe, the exhaust pipe inner pipe does not make direct contact with the exhaust pipe outer pipe, a combustion chamber is arranged in the exhaust pipe inner pipe, and the combustion chamber is arranged in the exhaust pipe inner pipe; the combustion chamber is provided with a fuel gas inlet, a combustion air inlet and an exhaust hole, fuel gas enters the combustion chamber through the fuel gas inlet, combustion air enters the combustion chamber through the combustion air inlet, and waste gas generated by combustion of the fuel gas is exhausted out of the combustion chamber through the exhaust hole and enters an inner pipe of the exhaust pipe. A first cooling air inlet and a second cooling air inlet are formed in the left side and the right side of the outer exhaust pipe correspondingly. The LNG ship comprises the gas combustion device. A heat insulation layer is prevented from being laid on the outer wall of the exhaust pipe, the diameter of the outer pipe of the exhaust pipe is smaller than that of an exhaust pipe with a heat insulation layer laid in the prior art, and therefore the ship space utilization rate is increased.

The invention belongs to the field of nano material preparation, and particularly discloses a preparation method and application of a narrow-diameter-distribution carbon nanotube, and the preparation method comprises the following steps: heating raw material mixed gas to 900-1500 DEG C for reaction, and introducing pulse gas in the reaction process to prepare the carbon nanotube, the raw material mixed gas contains a catalyst, a carbon source and an etching agent; the heating comprises at least two methods of plasma heating, microwave heating, silicon carbide rod heating, silicon molybdenum rod heating, resistance wire heating and electromagnetic induction heating. According to the preparation method disclosed by the invention, the high-quality narrow-diameter-distribution single-wall / double-wall carbon nanotubes can be prepared on a large scale, the single-time continuous operation time in actual production exceeds 45h, the unit yield can reach more than 190g / h, the purity of the product single-wall / double-wall carbon nanotubes is greater than 85%, the average G / D ratio is greater than 85, and the quality and the yield of the prepared carbon nanotubes are remarkably improved.

The invention relates to a ship fuel double-wall pipe isolation system, and relates to the technical field of isolation systems, the ship fuel double-wall pipe isolation system comprises a transportation main pipe, one side of the transportation main pipe is connected with a detection pipe, and the two ends of the detection pipe are correspondingly communicated with the transportation main pipe; a control valve body is arranged at the position, located between the two ends of the detection pipe, of the conveying main pipe, a detection assembly for detecting the interior of the detection pipe is arranged on the detection pipe, and a pipeline sealing assembly is arranged on the conveying main pipe. The system has the effects of monitoring the fuel in real time and finding leakage in time in the fuel transportation process.

The utility model discloses a triode device based on a single double-walled carbon nanotube structure. The triode device comprises a single double-walled carbon nanotube; an inner-layer carbon nanotube of the double-walled carbon nanotube is provided with a source electrode and a drain electrode which are made of a boron-doped P-type material, and a field effect transistor channel is formed between the source electrode and the drain electrode; an outer-layer carbon nano tube of the double-wall carbon nano tube forms a grid electrode through axial cutting and has the property of an N-type material; and the P-N junction is formed between the P-type material and the N-type material. According to the triode device, nanoscale high integration is realized, the interface and contact resistance problems of a traditional single-walled carbon nanotube field effect transistor are solved, the challenge of material coupling is avoided, the size of the device is reduced, and the nanoscale limitation of the prior art is broken through. The device adopts a single material, so that the uniformity and controllability are enhanced, the current driving and electrical properties are improved, the characteristics of low power consumption and quick response are shown, and the device is suitable for novel photoelectric and flexible electronic devices.

The invention discloses a construction method of an improved lock catch steel pipe pile cofferdam with a poor sand large-particle-size pebble covering stratum. The construction method comprises the following steps that an upper structure of a drilling platform is dismantled; measuring and setting out a pile position of the lock catch steel pipe pile cofferdam, sinking and positioning the steel pipe pile cofferdam by adopting a crawler crane and a vibratory hammer, and preliminarily entering a pebble bed; driving a pipe pile to a set elevation by utilizing a hydraulic impact hammer; for a steel pipe pile which is difficult in drilling footage or provided with boulders at the bottom, an XR280 rotary drilling guide hole is adopted; the steel pipe piles are smoothly closed; cofferdam water pumping; a small excavator is adopted for internal excavation, slag is discharged in a long arm excavation up-and-down transfer mode, a local rock stratum is firstly crushed and then excavated through a crushing hammer, water is pumped to the position 70 cm below an inner support of the road, and after the inner support is installed, water pumping continues to be conducted; and bottom sealing, pile head breaking and pile cap construction are carried out. By means of the construction method, the problems that the double-wall steel cofferdam is difficult to put down and level, and the site requirement is high can be effectively solved; the defects that a long steel sheet pile cofferdam is low in rigidity, prone to deformation and poor in water stopping effect are overcome. Through the cofferdam construction technology of the hydraulic impact hammer and the guide hole in the pipe of the rotary drilling rig, the hydraulic impact hammer is used for driving the steel pipe pile, the guide hole in the pipe of the rotary drilling rig and the pile-forming construction of a single pipe pile only need 10 minutes, and the construction period is greatly shortened.

The invention provides a marine ammonia fuel ventilation system and a control method and a control system thereof. The control method comprises the following steps: before a host is not connected, communicating an inlet pipe and a return pipe of an outer pipe of a double-wall pipe together, and carrying out an annular space tightness test; carrying out a leakage test on the valve, and testing whether the pneumatic double-stop ventilation valve is in a normal working state or not; when ammonia gas is detected, low-pressure nitrogen purging is started, and the ammonia gas is purged to an ammonia gas treatment device. By means of a high-pressure nitrogen automatic pressure testing mode, pipeline testing is conducted before the ventilation system is used, and it is ensured that the system is safe and reliable when used every time; a nitrogen purging valve group of the ammonia fuel ventilation system is provided with a tightness self-checking program, and the tightness of the valve is checked before each operation, so that the safety and reliability of the system are ensured when the system is used each time; besides a high-pressure nitrogen purging mode, a low-pressure nitrogen purging mode is designed, ammonia gas is purged to the ammonia gas treatment device, it is guaranteed that no ammonia gas leaks, and the safety of the system is improved.

The invention belongs to the technical field of diesel engine double-wall pipe correcting tools, and particularly relates to a low-speed diesel engine double-wall pipe correcting tool for a methanol dual-fuel ship. One end of the first pipe clamp rotating piece and the first pipe clamp fixing piece are connected and buckled through the first connecting bolt to form an arc-shaped clamping face matched with the outer diameter of one end of the double-wall pipe; one end of the second pipe clamp rotating piece and the second pipe clamp fixing piece are connected and buckled through a second connecting bolt to form an arc-shaped clamping face matched with the outer diameter of the other end of the double-wall pipe, the first pipe clamp and the second pipe clamp move in the same direction or in the opposite directions by rotating the adjusting component, and therefore axial thrust or pulling force is generated. Therefore, radial force is applied to the double-wall pipe arranged in the arc-shaped clamping faces of the first pipe clamp and the second pipe clamp, and the size of the double-wall pipe is corrected to the range required by a drawing. The device is high in correction efficiency, low in labor intensity, easy in precision control and good in universality.

The present invention relates to a method for air-drying solid, plasticizable material for use in a device for producing a three-dimensional object by means of additive manufacturing with material preparation, and to a corresponding device for producing the three-dimensional object from solid, plasticizable material with at least one additive manufacturing unit. A heated gaseous substance is introduced via a cavity (10) of a double-walled material feed nozzle (5) arranged between a material reservoir (2) for the solid material and a material feed zone (7) of a plasticizing unit (1) for plasticizing the solid material.The heated gaseous substance then emerges from the cavity (10) of the double wall (8, 9) of the material feed nozzle (5) near the material feed zone (7) and rises through the material feed nozzle (5) to the material reservoir (2), flowing around the solid material.

The utility model discloses a fuel supply and security system for a marine ammonia fuel engine, including a liquid ammonia fuel tank, a nitrogen tank, a fuel supply skid unit, an ammonia capture unit, a high-pressure common rail double-wall pipe, a central control unit and a collection tank. The utility model significantly improves the safety and stability of the marine ammonia fuel engine. The fuel supply skid unit realizes high-coverage high-pressure purge of ammonia accumulation at the bottom of the fuel supply skid unit box and high-efficiency discharge and replacement of gaseous ammonia. The nitrogen capture unit can not only process pure ammonia vapor volatilized from the liquid ammonia storage tank, but also process ammonia-nitrogen mixed gas sent from the fuel supply skid and the collection tank, effectively increasing the working margin and processing capacity of the ammonia capture unit.

The invention discloses an HPPM double-wall corrugated pipe with a round inner part and a square outer part and made of nano-modified polypropylene, and belongs to the technical field of electrical accessories. The corrugated pipe sequentially comprises a first square outer wall, a second square outer wall, a third square outer wall, a fourth square outer wall, a fifth square outer wall, first concave corrugations, second concave corrugations, third concave corrugations, fourth concave corrugations and a circular inner wall from outside to inside. The material is prepared from components in parts by weight as follows: 70-90 parts of homo-polypropylene, 9-20 parts of insulating filler, 5-15 parts of a modified nano-composite, 5-10 parts of modified temperature control capsules, 4-8 parts of a flame retardant, 0-10 parts of color master batches, 2-5 parts of carbon nanotubes, 2-4 parts of a flexibilizer, 1-3 parts of a coupling agent, 1-2 parts of calcium stearate and 1-2 parts of a stabilizer. The corrugated pipe prepared by the invention has excellent mechanical property, high temperature resistance, electrical insulation property and flame retardant property.

A method of manufacturing a heat exchanger tube is disclosed. The method may include folding a single sheet of material onto itself to form a folded sheet of material and forming first and second pluralities of ridges on a first portion of the folded sheet and a second portion of the folded sheet. The method may further include folding the first portion about a first portion distal end to overlay on a third portion of the folded sheet, and the second portion about a second portion proximal end to overlay on a fourth portion of the folded sheet. Furthermore, the method may include folding the third inner portion about a third portion distal end to overlay on a fifth portion of the folded sheet and folding the fourth portion about a fourth portion proximal end to overlay on the fifth portion to form the heat exchanger tube.

The invention relates to a mounting method for a top deck section and a double-wall pipe of a fuel cabin of a dual-fuel container ship. The deck section is divided into a deck assembly, an A-area longitudinal bulkhead assembly, a B-area longitudinal bulkhead assembly and a C-area longitudinal bulkhead assembly; the deck assemblage and the C-area longitudinal bulkhead assemblage are separately constructed, and the A-area longitudinal bulkhead assemblage is integrally constructed when the deck assemblage is constructed; longitudinal bulkheads in the B area are assembled and manufactured in bulk; sand washing and coating are conducted; mounting the B-area longitudinal bulkhead assemblage in bulk under the inverted placement of the deck assemblage: respectively mounting four longitudinal bulkhead plates of the B-area longitudinal bulkhead assemblage on the deck assemblage, enabling a double-wall pipe to penetrate through the four longitudinal bulkhead plates of the B-area longitudinal bulkhead assemblage, and mounting rib plates among the four longitudinal bulkhead plates; and the C-area longitudinal bulkhead assemblage is carried on the B-area longitudinal bulkhead assemblage. According to the method, the deck is segmented and divided into different assemblies for construction, after sand washing and coating are conducted, the double-wall pipe is installed, and the assemblies are folded and carried, so that the double-wall pipe is prevented from being damaged.

A marine liquid ammonia fuel supply system capable of cooling a diesel nozzle utilizes a liquid ammonia supply system matched with a dual-fuel main engine and cold energy of low-temperature liquid ammonia fuel, a cylinder in the dual-fuel main engine is provided with an ammonia fuel nozzle and the diesel nozzle, and a heat exchange coil is wound outside the diesel nozzle. Liquid ammonia is injected into a cylinder through an ammonia fuel nozzle to combust and do work, after an ammonia fuel mode of the dual-fuel main engine is finished, nitrogen is utilized to purge a fuel supply pipeline and the interior of the dual-fuel main engine, a gas-liquid mixture is purged to an ammonia gas treatment unit through a backflow double-wall pipe to be subjected to gas-liquid separation, separated liquid ammonia returns to a buffer tank, and the ammonia fuel mode of the dual-fuel main engine is finished. And the separated gas is guided into the ammonia gas absorption device through the receiving tank. The cooling function of the main engine on the nozzle in the diesel oil mode can be achieved, and compared with a traditional technical scheme that a fresh water cooling system is independently arranged, the cooling system has the advantages of being low in cost, small in extra occupied space, simple in system configuration, good in cooling effect, capable of saving energy, reliable in operation and the like.

The utility model discloses a heatable intake manifold suitable for a methanol engine, which comprises an intake manifold main body and an intake manifold heating branch, interlayers are arranged in double walls of the intake manifold main body, the intake manifold heating branch comprises a temperature control throttle valve, an intake manifold interlayer and a reversing valve, the intake manifold interlayer is provided with a water inlet, and the reversing valve is provided with a water outlet. Fin plates are embedded in the air inlet manifold interlayer, electric heating wires are embedded in the air inlet manifold interlayer, a water inlet of the air inlet manifold interlayer is connected to a temperature control throttling valve through a water channel, an output port of the temperature control throttling valve is connected to a water outlet main pipe, and a water circulation pipeline passes through a wax type thermostat from the water outlet main pipe. The thermostat first water circulation of the wax type thermostat is that the wax type thermostat is connected with a reversing valve and then is connected to an engine cylinder sleeve, and the thermostat second water circulation connected with the output end of the wax type thermostat is that the wax type thermostat is connected to a water tank and is connected to the engine cylinder sleeve through the water tank. According to the utility model, the direct heating of the intake manifold is efficiently realized, and the heating efficiency of the intake mixed atmosphere is improved.

The invention relates to a double-walled tube for an aircraft fuel system, an aircraft fuel system and an aircraft. The double-walled tube includes an inner wall defining a first open end, a second open end, and an interior region connecting the first open end to the second open end and via which fuel can flow through the double-walled tube in use. The double-walled tube also includes an outer wall disposed at least partially around the inner wall to define a void between the inner wall and the outer wall, the void being fluidly isolated from the interior region. The double-walled tube also includes at least one barrier that is openable to create a passage that fluidly connects the void to the interior region. The at least one barrier is configured to open when a pressure in the void is higher than a pressure in the interior region.

The invention discloses an optimized arrangement structure of a low-pressure gas pipe route for an LNG (liquefied natural gas) dual-fuel container ship, which comprises an LNG fuel cabin, a gas preparation room and a cabin area, the gas preparation room is arranged above the LNG fuel cabin, the gas preparation room is communicated with the cabin area through a low-pressure gas pipe, and the cabin area is communicated with the LNG fuel cabin. And the low-pressure gas pipe is arranged in a way that the gas preparation room passes through the longitudinal hatch coaming area above the main deck and is connected to the cabin area. According to the invention, the gas pipe is arranged in the open area above the main deck and the joints of the pipes are all welded, so that a single-wall pipe replaces a double-wall pipe, the channel arrangement of the main deck is not influenced, the length of the gas pipeline is not increased, and the construction cost is reduced.

Disclosed is a double-wall pipe 10 for an aircraft fuel system. The double-wall pipe 10 comprises an inner wall 11 defining a first open end, a second open end, and an inner region 14 connecting the f

The invention relates to the technical field of cooling of turbine blades of gas turbines, and discloses a novel small-channel double-wall cooling structure with communicated gaps, and flow baffles are designed in air supply channels, so that the phenomenon of cold air migration in internal channels of impact divergence double-wall blades can be effectively improved; the gaps are formed in the flow baffles to supply cold air to the air film holes, the cold air impacts on the inner wall face of the outer layer plate through the impact holes and strengthens heat exchange, impact jet flow impacts on the inner wall face to form wall face flow, then the wall face flow passes through the gaps, the heat exchange intensity of the gap areas is strengthened, and finally the cold air flows out through the air film holes. Cold air covering is formed on the outer side of the outer layer plate to isolate high-temperature main flow. And the cold air migration phenomenon in an internal channel of the double-layer-wall blade is reduced, meanwhile, the surface average comprehensive cooling efficiency can be improved, and the uniformity of blade temperature distribution is improved.

The invention discloses an internal combustion type carbonization system based on material whole-course spiral propulsion, which comprises a carbonization furnace, a feeding auger, an ignition device, a first air blower and a second air blower, the carbonization furnace linearly extends along the left-right direction, and the right end of the carbonization furnace is provided with a carbon discharge port; a drying preheating area, a main carbonization spontaneous combustion area and a burnout carbon discharge area are sequentially formed in the hearth in the advancing direction of materials; through the partition design in the hearth and the whole-course penetrating layout of the feeding auger feeding pipe, materials are turned over, fed and carbonized in the pipe at the same time, and the problems of uneven carbonization and product quality fluctuation caused by static material accumulation or simple pushing of traditional external combustion type equipment are thoroughly solved; meanwhile, due to the internal combustion type design, pyrolysis gas can be spontaneously combusted in the furnace, heat directly acts on a feeding pipe and materials, heat loss caused by external combustion type double wall surface conduction is avoided, the heat utilization rate can be greatly improved, system self-circulation can be achieved under the condition that external continuous energy supply is not needed, and the operation cost is reduced.