36results about How to "Improve surge margin" patented technology

A casing for a turbomachine rotor wheel includes a plurality of circumferential grooves, each of substantially constant section, with the section areas of the circumferential grooves decreasing from upstream to downstream on going from the first groove to the last groove. By treating the casing in this way, the efficiency of the rotor wheel is optimized and its surge margin is improved.

An object is to position a plurality of guide vanes for generating swirl flow at a housing inner circumferential side in front of an impeller wheel to improve a surge margin and to restrict the decrease in a choke flow rate, thereby increasing an operation range of a compressor. A compressor 19 includes a compressor housing 15, an impeller wheel 7 which compresses intake gas flowing in from an intake-air inlet 23, a swirl-flow generating part including a plurality of guide vanes 55 disposed circumferentially along an inner circumferential wall of the intake-air channel 21 between the intake-air inlet 23 and the impeller wheel 7 and which swirls the intake gas from the intake-air inlet 23 around the rotational axis, and a central intake-air flow path 59 formed inside the guide vanes 55 to allow intake gas to flow to the impeller wheel 7 without passing through the guide vanes 55.

Methods and systems are provided for improving a margin to surge. A compressor recirculation valve is held at a semi-open position during steady-state boosted engine operation and operation in a soft surge region. The valve is fully opened to reduce hard surge, or fully closed to meet a transient increase in boost demand.

The invention discloses a supercharging stage device and a turbofan engine. The supercharging stage device is used to be arranged in the turbofan engine. The supercharging stage device includes an internal passage and a supercharging stage assembly. The supercharging stage assembly is arranged in the internal passage. The connotation channel has an inlet and an outlet. The inlet is connected to the inlet of the turbofan engine, and the outlet is connected to the inlet of the high-pressure compressor. The supercharging stage assembly includes the first supercharging stage and the second supercharging stage. Between the inlet and the second supercharging stage, the supercharging ratio of the first supercharging stage is set lower than that of the second supercharging stage, and the pressure ratio distribution of the first supercharging stage and the second supercharging stage is passed through The load factor is adjusted, and the load factor of the first supercharging stage is 9%~15% lower than that of the second supercharging stage. The supercharging stage device of the present invention makes the supercharging ratio of the first supercharging stage smaller than the supercharging ratio of the second supercharging stage by changing the design scheme of the highest supercharging ratio of the traditional first supercharging stage, thereby increasing the supercharging stage The surge margin of the internal channel of the device.

The invention discloses a super / transonic compressor with front sharp and blunt trailing edge bodies and a design method of the super / transonic compressor, and belongs to the technical field of aero-engine compressors. The super / transonic compressor is characterized in that the multiple sharp and blunt trailing edge bodies with certain height, length and width are evenly distributed on an outer machine case of an inlet of the compressor in the circumferential direction. The super / transonic compressor can be directly used as a high-performance aviation gas turbine engine compressor. On the premise that the layout and the pneumatic performance of an existing compressor are not changed, the stable working margin of the compressor is substantially improved. According to the super / transonic compressor, due to the fact that the front sharp and blunt trailing edge bodies are reasonably designed, the super / transonic compressor not only can work normally under the condition that only one gas inlet angle exists, but also can work normally under the condition that a certain positive attack angle or a certain negative attack angle is formed between the gas inlet direction and the front edge of an attracting force face, and the stable working margin of the compressor is improved on the premise that the efficiency of a fan or the compressor is not changed basically.

The invention discloses an axial flow-centrifugation integral bladed disc type combined compression system. An axial flow impeller and a centrifugal impeller are integrally connected to form an integral bladed disc; an axial flow stator is arranged between an axial flow rotor and the centrifugal impeller; an impeller outer ring of an axial flow gas compressor and an impeller outer ring of a centrifugal gas compressor are integrally connected to form an integral impeller outer ring; one assembling reserving cavity for assembling stator outer rings is formed in the integral impeller outer ring; the axial flow stator is divided into a plurality of equal parts in the circumferential direction; the stator outer rings equally divided are mounted in the assembling reserving cavity; the stator outer rings are limited in the radial direction through a cylindrical surface at the top of the assembling reserving cavity; and the stator outer rings are compressed through compression rings. The axial flow-centrifugation integral bladed disc type combined compression system simplifies the structure to improve the reliability of an engine and reduce the production cost; a cantilever stator is adopted to increase the surge margin of an axial flow gas compressor stage so as to further increase the surge margin of the combined compression system and expand the operational covered wire of the engine.

The invention provides a casing treatment structure for improving the surge margin of a single-stage centrifugal compressor, and relates to the technical field of compressors. A surge expanding through hole is arranged on a casing ingeniously, when the air inlet amount needed by the compressor is increased, part of air enters the casing from the surge expanding through hole, so that the amount of air entering the casing from an air inlet way is reduced, and the surge margin is accordingly increased. Furthermore, the direction of the surge expanding hole is set to form a certain angle with a tangent line of the inner diameter of the air guide casing, so that airflow entering the casing from the surge expanding hole is basically the same in circumferential speed direction of airflow. The casing treatment structure is simple in process, low in product cost, safe, reliable, easy to maintain and simple in structure, and the compressor surge margin can be obviously improved.

The invention discloses a design method of an impeller. The rapid and accurate impeller design method is provided, the aerodynamic performance and the design efficiency of the impeller are improved, and the method comprises the steps of giving the impeller dimensionless parameters; setting an initial enthalpy rise coefficient; calculating the optimal centrifugal impeller inlet impeller cover relative axial airflow angle; calculating the centrifugal impeller inlet impeller cover relative mach number; calculating the enthalpy rise coefficient; judging whether the relative error between the enthalpy rise coefficient and the initial enthalpy rise coefficient is smaller than 1% or not, if the relative error is larger than or equal to 1%, resetting the initial enthalpy rise coefficient; if the relative error is smaller than 1%, judging as iterative convergence and performing the next step; calculating the ratio of the centrifugal impeller inlet impeller cover diameter to the centrifugal impeller outlet diameter and the ratio of the centrifugal impeller outlet width to the centrifugal impeller outlet diameter; giving the centrifugal impeller dimensional parameters; and according to the calculation result and the given parameters, obtaining impeller design parameters. Through the method, the aerodynamic performance of the impeller can be improved, and the design period can be shortened.