Water-jet drilling (WJD) is an effective method for stimulating, exploring, and developing oil and gas resources. The self-rotatory water-jet bit (SRWJB) is a type of potentially efficient bit appl...

Study of the rock-breaking and drilling performance of a self-rotatory water-jet bit in water-jet drilling and its influential factors

The invention provides a combustion chamber head provided with V-shaped grooves matched with a swirler. The combustion chamber head adopts a level-to-level regionalized combustion scheme. The head mainly comprises an on-duty level and a main combustion level. The central on-duty level is provided with a dual-stage axial swirler body (same in swirling direction), the outer side main combustion level is provided with a third-stage axial swirler body (opposite to the central on-duty level in swirling direction), and all stages of swirler blades are connected through the V-shaped grooves so as toform a netty structure. The central on-duty level adopts a centrifugal spray nozzle to perform fuel oil injection, and the outer side main combustion level adopts a multi-point direct-injection type spray nozzle to perform fuel oil injection. According to the combustion chamber head provided by the invention, the V-shaped grooves in the head of the swirler can be used for completing flow guiding of air at an inlet of a combustion chamber and completing injection of different working media under different working conditions; and meanwhile, the V-shaped grooves are matched with the swirler blades to form the netty structure, reasonable and uniform combustion chamber centrifugal force distribution is formed, accordingly, oil-gas mixing is enhanced, the combustion efficiency is improved, and pollutant discharging is reduced.

Combustion chamber head provided with V-shaped grooves matched with swirler

The invention discloses a trailing edge blowing type stabilizer structure suitable for incoming flow distortion. The trailing edge blowing type stabilizer structure is mainly composed of an annular stabilizer and a radial V-shaped groove standby stabilizer. During operation, head-on incoming flow is sucked into a mixing chamber through a stabilizer suction slit, spray atomized fuel oil is furthersheared and atomized at the edge of a baffle, the fuel oil evaporates in the mixing chamber and is blended with gas stream, most oil and gas mixture is further atomized and blown out with the trailingedge to be mixed with the incoming flow for combustion and to be rolled into a recirculation zone, a small amount of oil and gas mixture blown out from the suction slit of the baffle enhances combustion in the recirculation zone, flame stability under the incoming flow distortion condition can be achieved, the length of a mixing zone before the combustion chamber is effectively shortened, the difficulty of the high combustion chamber inlet airflow velocity and the uneven temperature distribution are overcome, the problem about stability of an oil supply device, ignition and flame is solved, the fuel oil atomization quality and the ignition performance are improved, the combustion efficiency is improved, and the stable working range of the combustion chamber is widened.

Trailing edge blowing type stabilizer suitable for incoming flow distortion

The invention provides a structure design scheme of a single-ring evaporator tube for a micro-engine combustion chamber. The evaporator tube can effectively enhance heat exchange, increase the residence time of mixed air, and improve the atomization and evaporation effect of fuel. Radial V-groove flame holders are reasonably designed and arranged on the inner and outer sides of the evaporator tube. A pre-evaporated fuel gas mixture is obtained in the annular evaporator tube, flows into the V-groove flame holders, further evaporates in the V-groove flame holders, and enters the combustion chamber for combustion from fuel holes on both sides of the V-shaped flame holders. Since the evaporator tube is placed in a main combustion zone of the combustion chamber, the heat exchange effect is obvious, and the fuel can be sufficiently evaporated. Since the radial V-shaped groove flame holders are circumferentially distributed along the central axis, the fuel gas mixture is evenly distributed, and so the unevenness of the combustion is avoided and the temperature distribution of the combustion chamber outlet is improved. Furthermore, combustion gas forms a recirculation zone behind the radial V-shaped groove flame holder, the residence time of the combustion gas is longer, which has obvious improvement effect on flame stabilization and combustion efficiency.

Structure design of single-ring evaporator tube for micro-engine combustion chamber

The invention discloses a secondary-flow evaporation tube type combustion chamber structure. A combustion chamber body and a baffle plate are adopted, wherein the front end of the combustion chamber body is shaped like a cylinder, and the upper end of the baffle plate is provided with an annular groove; the baffle plate is additionally arranged on an outer wall surface of a combustion chamber, andair film holes are formed in the annular cylindrical barrel wall and the groove wall of the annular groove, so that the reverse air flow of a secondary flow in a casing is heated and heated again after being injected by a primary air flow at the head of the combustion chamber and mixed; and then the combustion flame temperature field is more uniform, the heat transfer of the fin reinforced wall surface enables the temperature of the wall surface to be effectively decreased, the uniformity of the flow field is optimized, the combustion efficiency is improved, and the emission of pollutants such as NOx is greatly reduced while fuel is saved. The annular cylindrical outer wall and the inner wall of the annular groove are connected through fins to form an integrated forming structure, the overall weight of the device is reduced, the outline size of the combustion chamber is decreased, the thrust ratio of an engine is effectively increased, and the maneuverability of the engine is increased; and the using number of connecting parts between structural members is decreased at the same time, and the overall performance is improved.

Secondary-flow evaporation tube type combustion chamber structure

The invention provides a combined cooling type rectification support plate flame stabilizer. According to the combined cooling type rectification support plate flame stabilizer, design of impacting and cooling array size and distribution, design of air film cooling hole size and distribution, design of oil spraying hole size and distribution and design of oil passages in the rectification support plate flame stabilizer and a jetting form are involved. According to the combined cooling type rectification support plate flame stabilizer, a cool air cavity is formed in an ordinary rectification support plate flame stabilizer, and through arrangement of an impacting array and air film cooling holes, the wall temperature of the rectification support plate flame stabilizer is controlled; and an oil spray pipe is subjected to cooling protection to a certain extent, coking blocking caused due to overheating of the oil spray pipe is avoided, the work reliability of the rectification support plate flame stabilizer is improved, and the service life of the rectification support plate flame stabilizer is prolonged.

Combined cooling type rectification support plate flame stabilizer

The invention provides an annular oil supply type integrated afterburner. A worm gear rear rectification supporting plate and a flame stabilizer are integrated, two stages of rectification supportingplates and the flame stabilizer are subjected to radially misplaced structure design, and in this way, a stable low speed backflow area large in size range and high in swirl flowing is more easily formed at the downstream of the annular oil supply type integrated afterburner. A whole-ring groove stabilizer is arranged between the two stages of rectification supporting plates. An oil cavity is formed inside a force-adding inner cone and is connected with a fuel channel inside the first-stage rectification supporting plate, and after absorbing heat of the force-adding inner cone, fuel finally reaches the inside of the whole-ring groove stabilizer. Main fuel is sprayed out longitudinally from the two sides of the whole-ring groove stabilizer, on-duty fuel is sprayed out from a groove of the whole-ring groove stabilizer to form on-duty flame, and soft ignition is achieved. By reasonably forming nozzle small holes, the atomization effect of the fuel can be effectively improved, and thus thestability and combustion efficiency are improved. The annular oil supply type integrated afterburner has the advantages that the two stages of rectification supporting plates which are radially misplaced are adopted, and a better backflow area is formed; meanwhile, through longitudinal oil spray of the whole-ring groove stabilizer, the fuel-gas mixing effect is improved, the on-duty flame is formed, the soft ignition is achieved, and thus the combustion stability is effectively improved.

Annular oil supply type integrated afterburner

The invention provides an integrated afterburner with double oil circuits and a truncated central cone structure, so that a fuel oil atomization effect can be effectively improved, the oil-gas mixturedegree is improved, the mixed gas staying time is prolonged, and the combustion efficiency is improved. The fuel oil is divided into two streams so as to enter a main oil circuit fuel oil channel andan auxiliary oil circuit fuel oil channel in a rectifying support plate flame stabilizer; the fuel oil of the main oil circuit is sprayed out through small oil spray holes in the surface of the rectifying support plate flame stabilizer; and the fuel oil of the auxiliary oil circuit absorbs heat in the fuel oil channel and is finally sprayed out through small oil spray holes in the surface of a truncated central cone. Due to the structure design of the truncated central cone, an airflow circulation area is enlarged suddenly, and mixed gas of inner and outer duct parts is entrained to the center area after flowing through the truncated central zone so as to form a strong return flow zone structure and is sufficiently mixed and burned with the fuel oil sprayed by the auxiliary oil circuit inthe zone. Due to the long staying time, an oil-gas atomization effect is good, and the burning efficiency and the stability are improved.

Integrated afterburner with double oil circuits and truncated central cone structure

Lean-premixed combustion technology has been adopted widely for heavy-duty gas turbine application. The multiple-swirl structure might shorten the flame brush length and reduce emissions. However, ...

Zhang Peng

Papers

Combustion chamber head provided with V-shaped grooves matched with swirler

Combined cooling type rectification support plate flame stabilizer

Annular oil supply type integrated afterburner

Integrated afterburner with double oil circuits and truncated central cone structure

Numerical investigation of inlet guiding ring effect on combustor flow field with multiple swirler structures