38results about How to "Improve the diffusion capacity" patented technology

The invention provides a diffuser end wall of a turbine single-side exhaust system and relates to the technology of turbines. The end wall face adopts full three-dimensional modeling, different meridian lines at different circumferential directions are utilized to generate a non-axis-symmetrical full three-dimensional diffuser end wall curve. The diffuser end wall structure has the advantage that the end wall adapts to actual flow field distribution of a last stage turbine outlet, ensures that the exhaust system has good diffusion capability under the actual operation environment of a unit, turbine outlet back pressure is reduced, turbine power output is increased, unit heat efficiency is improved, and the end wall adapts to an exhaust volute conducting single-side radial exhausting, reduces circumferential flowing uneven degree in the single-side radial exhaust system, reduces last stage turbine blade load and fluctuation of air power in one circle and improves unit operation safety. The diffuser end wall structure mode is suitable for diffusers in all turbine exhaust systems conducting single-side radial exhausting.

The invention discloses an ejection low total pressure cold medium adjustable secondary throat diffuser. The ejection low total pressure cold medium adjustable secondary throat diffuser is used at thedownstream of a large hypersonic velocity wind tunnel experimental section, can adapt to operating condition of a wider range by adjusting the amount of ejection air, meanwhile, diffusion capacity isimproved, the working load of a back section ejector is reduced. In addition, a cold medium ejected flows at a near wall region, and the wall surface of the diffuser can be effectively protected frombeing in contact with high temperature fuel gas directly, and the construction cost brought by a cooling water sleeve can be reduced. The novel structure of the diffuser is characterized in that a side wall groove is added in the front of a diffuser convergence section, low total pressure normal temperature air is introduced at the position of the front edge of the groove and used as the cold medium, an air film is formed in the wall surface of the diffuser through the ejection and diffusion effect, the practical flow diameter of a secondary throat is adjusted, the static pressure recovery capability of secondary throat is adjusted at a greater degree, meanwhile, heat load of the wall surface of the secondary throat is reduced again, and the wall surface is cooled; and simulation verification is carried out, even though the ejection cooling medium is an atmospheric condition, the good diffusion and cooling effect can be achieved.

The invention discloses a blade root slotting gas compressor stator with gradual-contraction changes of the slot span-wise height, and relates to the driven flowing control technology in the technical field of turbo machines. A slot of the equivalent-width span-wise height gradual-contraction type is formed from a pressure face to a suction face at the blade root of a blade grid of the gas compressor stator, and the streaming pressure difference of a blade is utilized for forming jet flow to restrain and delay flow separation. One or more slots are formed in the blade root of the blade grid of the gas compressor stator. A slot inlet is formed in the pressure face of the blade grid of the stator, and a slot outlet is formed in the suction face of the blade grid. The widths of the slots are equivalent, the slot inlet is higher than the slot outlet, the contraction slot is formed in the slot height direction, and the distance between the upper wall face and the end wall of each slot is in smooth transition. The blade root slotting gas compressor stator has the beneficial effects that kinetic energy of low-energy fluid of boundary layers at the end wall and the suction face outlet of the slot is supplemented through the jet flow of the slot, airflow of the boundary layer of the suction face of the blade grid and the boundary layer of the end wall are blown away, and flowing separation is restrained and delayed, so that the pressure expansion capacity of the portion behind a blade grid channel is recovered.

The invention discloses an integrated pneumatic design method of an axial-flow turbine and a single-side radial steam / gas discharging system. The method comprises: a) carrying out multiple-purpose design on the axial-flow turbine; b) under the real entry condition, carrying out multiple-purpose design on the single-side radial steam / gas discharging system; and c) carrying out matching analysis on the axial-flow turbine and the single-side radial steam / gas discharging system. The method has the following three effects: 1, the steam / gas discharging system is ensured to have good pressure-expanding capacity under the actual operation environment, thereby reducing the outlet backpressure of the turbine, increasing the output power of the turbine and improving the heat efficiency of a unit; 2, the uneven degree of the flowing circumference in the single-side radial steam / gas discharging system is weakened, and the fluctuant amplitude of an aerodynamic force of a moving blade of the turbine in a round is reduced; and 3, the low-frequency unsteady aerodynamic force of the turbine blade surface caused by flowing instability inside the steam / gas discharging system is reduced, and the operation safety of the unit is improved. The method disclosed by the invention is suitable for pneumatic design of the turbines and steam / gas discharging systems of all the axial-flow turbines / gas turbines for single-side radial steam / gas discharging.

A centrifugal fan (23) is provided with a hub (15), blades (21), and a shroud (19). Each of the blades (21) has a curved section (21d) which is curved so as to be tilted to the side (21c1) on which an air current impinges when the connection end section (21c) where the blade (21) and the portion of the shroud (19) which protrudes inward are joined moves in the rotational direction of the centrifugal fan (23). The hub (15) has a hub-side diffuser ring (27) protruding to the outer peripheral side of the blades (21). The shroud (19) has a shroud-side diffuser ring (26) which protrudes to the outer peripheral side of the blades (21).

The invention discloses a design method of a centrifugal compressor and a diffuser structure. The centrifugal compressor comprises a shell, an impeller and a diffuser, wherein the impeller comprises ahub and impeller blades, the diffuser comprises diffuser blades; and the design method comprises the following steps that curve segments of the shell and the hub of the impeller adopt Bezier curve design, and curve segments of the impeller blades adopt 3D free curve design; and curve segments of the diffuser blades adopt spiral curve design. Through the parametric design method, a gas inlet angleat a gas inlet hole and a gas outlet angle at a gas outlet hole are optimized, a gas flow state is improved, the uniformity of an outlet gas flow is improved, the gas flow loss is reduced, and high gas compressing capability and diffusion capability are obtained under the condition of small size.

The invention discloses a diffuser of a centrifugal compressor. Improving the structure of the diffuser and further improving its working performance have important application value. In the present invention, a short blade is arranged in the flow channel of two adjacent long blades; the leading edge of the long blade is a curved surface and is inclined, and the angle between the leading edge line and the central axis of the wheel disc is 6-8°; the curvature of the leading edge of the long blade is The radius gradually increases along the direction from the wheel disc to the wheel cover; the long blade is provided with three broken-line grooves passing through the pressure surface and the suction surface; the trailing edge of the long blade is located on the pressure surface with a trailing edge tip. In the present invention, the short blades located in the flow channels of adjacent long blades suppress the occurrence of airflow separation on the blade surface; the zigzag channel reduces the pressure difference between the pressure surface and the suction surface, reduces the reverse pressure gradient, and effectively blows off the suction surface of some blade tails. The surface layer separates the airflow; the parabolic winglet at the trailing edge can inhibit the growth of the wingtip vortex generated by the pressure difference between the suction surface and the pressure surface of the trailing edge of the traditional airfoil blade.

The utility model relates to a compressor stator blade cascade with constant-depth grooves in the end wall. It includes a lower end wall, an upper end wall and a plurality of blades arranged side by side between the lower end wall and the upper end wall; the space between two adjacent blades is a cascade channel, the blades are arc plates, the inner arc surface is the pressure surface, and the outer arc The surface is the suction surface, and the inner and outer arc surfaces have two intersection lines in the axial direction. The intersection line near the intake direction is the leading edge line, and the intersection line near the outlet direction is the trailing edge line. The leading edge line and the trailing edge line The distance between them is the chord length of the blade, the height direction of the blade is the span direction, the direction of the connecting line between the same parts of the two blades is the circumferential direction, the length of the connecting line is the cascade pitch, and the direction perpendicular to the circumferential direction in the end wall plane is the axis. At least one groove is formed downwardly on the surface of the lower end wall at the part located in the blade cascade channel. The invention can significantly affect the flow field in the corner area, and under suitable design parameters, the circumferential groove end wall treatment can effectively reduce the total pressure loss coefficient of the compressor stationary blade cascade and improve the cascade diffusion capacity.