The high-load compressor plays an important role in further improving the performance of aero-engine.However,the complex shock waves in the cascade channel also bring more aerodynamic losses.This paper proposes a supe...The high-load compressor plays an important role in further improving the performance of aero-engine.However,the complex shock waves in the cascade channel also bring more aerodynamic losses.This paper proposes a supersonic compressor cascade modeling method based on the theory of unique inlet flow angle,and the aerodynamic design and optimization of a cascade with inlet Mach number 1.85 are studied by combining the numerical optimization method and planar cascade experiment.The results show that pressure increase can be achieved by multiple shock waves which are obtained by the reflection of the leading edge detached shock wave in the initial supersonic cascade channel at the design point,which verifies the feasibility of the design method.After optimization,the aerodynamic performance of the cascade has been improved to different degrees at the design point and off-design point.When the static pressure ratio is 3.285,the total pressure recovery coefficient reaches 86.82%at the design point,which is on the advanced level of the same type of cascade.The experimental results of planar cascade schlieren and surface pressure measurement also verify the correctness of the simulation method,which provides useful references for the subsequent compressor design.展开更多
To effectively reduce the loss of strong shock wave at the trailing edge of the supersonic cascade under high backpressure,a shock wave control method based on self-sustaining synthetic jet was proposed.The self-susta...To effectively reduce the loss of strong shock wave at the trailing edge of the supersonic cascade under high backpressure,a shock wave control method based on self-sustaining synthetic jet was proposed.The self-sustaining synthetic jet was applied on the pressure side of the blade with the blow slot and the bleed slot arranged upstream and downstream of the trailing-edge shock,respectively.The flow control mechanism and effects of parameters were investigated by numerical simulation.The results show that the self-sustaining synthetic jet forms an oblique shock wave in the cascade passage which slows down and pressurizes the airflow,and the expansion wave downstream of the blow slot weakens the shock strength which can effectively change the Mach reflection to regular reflection and thus weaken the shock loss.And the suction effect can reduce loss near blade surface.Compared with the baseline cascade,the self-sustaining jet actuator can reduce flow losses by 6.73%with proper location design and vibration of diaphragm.展开更多
To achieve efficient control of supersonic compressor cascade flow,a type of spanwise distributed pulsed arc discharge plasma actuation(PADPA)was designed.To simulate the influences of PADPA on the flow field,a phenom...To achieve efficient control of supersonic compressor cascade flow,a type of spanwise distributed pulsed arc discharge plasma actuation(PADPA)was designed.To simulate the influences of PADPA on the flow field,a phenomenological model was established.Then,the flow control effects of PADPA on supersonic compressor cascade flow were researched numerically.The results show that under low static pressure ratio condition,the compressive wave induced by PADPA reduced the intensity of the passage shock wave,which eventually reduced shock wave loss.It was also found that PADPA produced an adverse pressure gradient(pre-compression effect)around the actuation location,which reduced the strength of the high adverse pressure gradient induced by the passage shock wave.The airflow on both sides of the actuation location was accelerated by PADPA owing to the spanwise distributed layout.Thus,it improved the ability of the boundary layer to resist the effect of the adverse pressure gradient and reduced the separation zone.Consequently,the total pressure loss was reduced by 6.8%.Under high pressure ratio condition,the effect of PADPA on the suction side controlling the large separation of the boundary layer was insignificant.The total pressure loss also increased slightly.展开更多
Flow control methodologies have been widely used to eliminating flow separation and increasing the blade load in axial compressor.Aiming at revealing the flow mechanism of coupled bowed blading and boundary layer suct...Flow control methodologies have been widely used to eliminating flow separation and increasing the blade load in axial compressor.Aiming at revealing the flow mechanism of coupled bowed blading and boundary layer suction in a supersonic compressor cascade,a cascade with a diffusion coefficient of 0.62 is numerically presented.First of all,according to the available experimental data,the numerical method was validated;then,different bowed blading effects on flow field in detail were investigated;at last,based on the flow physics of purely bowed blading,the positively bowed blade was coupled with boundary layer suction on blade suction surface,whereas the negatively bowed blade was coupled with endwall suction.For coupled control method,influence mechanism on flow field,especially on the shock structure was revealed,and different aspect ratios of coupled control method were investigated as well.Results showed that the coupled positively bowed blading and suction surface suction can eliminate the flow separation effectively.Compared with that of baseline supersonic cascade,the total pressure loss coefficient of the coupled scheme was reduced by 37.4%at most.At mid-span,the shock moved downstream and the single shock was separated to a dual-shock structure since the positively bowed blading reduced the static pressure of mid-span.The coupled negatively bowed blading and endwall suction also effectively enhanced the performance of cascade by removing the corner separation,with the loss coefficient reduced by as much as 41.9%.However,the suction coefficient of optimal coupled negatively bowed blading scheme reached 10.5%,which is too high for practical use.After coupled control,the 3 D shock structure became“C”shaped distribution along spanwise because of the difference in influence mechanism of negatively bowed blading on different spanwise location.Due to the opposite influence effect of positively and negatively bowed blading,the shock structure in the two different schemes of cascades were different and showed opposite variation trends as aspect ratio increased.展开更多
基金funded by the National Science and Technology Major Project(J2019-II-0016-0037).
文摘The high-load compressor plays an important role in further improving the performance of aero-engine.However,the complex shock waves in the cascade channel also bring more aerodynamic losses.This paper proposes a supersonic compressor cascade modeling method based on the theory of unique inlet flow angle,and the aerodynamic design and optimization of a cascade with inlet Mach number 1.85 are studied by combining the numerical optimization method and planar cascade experiment.The results show that pressure increase can be achieved by multiple shock waves which are obtained by the reflection of the leading edge detached shock wave in the initial supersonic cascade channel at the design point,which verifies the feasibility of the design method.After optimization,the aerodynamic performance of the cascade has been improved to different degrees at the design point and off-design point.When the static pressure ratio is 3.285,the total pressure recovery coefficient reaches 86.82%at the design point,which is on the advanced level of the same type of cascade.The experimental results of planar cascade schlieren and surface pressure measurement also verify the correctness of the simulation method,which provides useful references for the subsequent compressor design.
基金co-supported by the National Natural Science Foundation of China(No.52075538)the National Science and Technology Major Project,China(No.J2019-II-0016-0037)+1 种基金the Natural Science Foundation of Hunan Province,China(No.2020 JJ2030)the Foundation of National University of Defense Technology,China(No.ZK-22-30)。
文摘To effectively reduce the loss of strong shock wave at the trailing edge of the supersonic cascade under high backpressure,a shock wave control method based on self-sustaining synthetic jet was proposed.The self-sustaining synthetic jet was applied on the pressure side of the blade with the blow slot and the bleed slot arranged upstream and downstream of the trailing-edge shock,respectively.The flow control mechanism and effects of parameters were investigated by numerical simulation.The results show that the self-sustaining synthetic jet forms an oblique shock wave in the cascade passage which slows down and pressurizes the airflow,and the expansion wave downstream of the blow slot weakens the shock strength which can effectively change the Mach reflection to regular reflection and thus weaken the shock loss.And the suction effect can reduce loss near blade surface.Compared with the baseline cascade,the self-sustaining jet actuator can reduce flow losses by 6.73%with proper location design and vibration of diaphragm.
基金supported by National Natural Science Foundation of China(Grant No.51790511,51906254)。
文摘To achieve efficient control of supersonic compressor cascade flow,a type of spanwise distributed pulsed arc discharge plasma actuation(PADPA)was designed.To simulate the influences of PADPA on the flow field,a phenomenological model was established.Then,the flow control effects of PADPA on supersonic compressor cascade flow were researched numerically.The results show that under low static pressure ratio condition,the compressive wave induced by PADPA reduced the intensity of the passage shock wave,which eventually reduced shock wave loss.It was also found that PADPA produced an adverse pressure gradient(pre-compression effect)around the actuation location,which reduced the strength of the high adverse pressure gradient induced by the passage shock wave.The airflow on both sides of the actuation location was accelerated by PADPA owing to the spanwise distributed layout.Thus,it improved the ability of the boundary layer to resist the effect of the adverse pressure gradient and reduced the separation zone.Consequently,the total pressure loss was reduced by 6.8%.Under high pressure ratio condition,the effect of PADPA on the suction side controlling the large separation of the boundary layer was insignificant.The total pressure loss also increased slightly.
基金sponsored by National Natural Science Foundation of China(Nos.51806174,51741601)National Science and Technology Major Project(No.J2019-II-0011-0031)National Natural Science Foundation of China(No.51790512)。
文摘Flow control methodologies have been widely used to eliminating flow separation and increasing the blade load in axial compressor.Aiming at revealing the flow mechanism of coupled bowed blading and boundary layer suction in a supersonic compressor cascade,a cascade with a diffusion coefficient of 0.62 is numerically presented.First of all,according to the available experimental data,the numerical method was validated;then,different bowed blading effects on flow field in detail were investigated;at last,based on the flow physics of purely bowed blading,the positively bowed blade was coupled with boundary layer suction on blade suction surface,whereas the negatively bowed blade was coupled with endwall suction.For coupled control method,influence mechanism on flow field,especially on the shock structure was revealed,and different aspect ratios of coupled control method were investigated as well.Results showed that the coupled positively bowed blading and suction surface suction can eliminate the flow separation effectively.Compared with that of baseline supersonic cascade,the total pressure loss coefficient of the coupled scheme was reduced by 37.4%at most.At mid-span,the shock moved downstream and the single shock was separated to a dual-shock structure since the positively bowed blading reduced the static pressure of mid-span.The coupled negatively bowed blading and endwall suction also effectively enhanced the performance of cascade by removing the corner separation,with the loss coefficient reduced by as much as 41.9%.However,the suction coefficient of optimal coupled negatively bowed blading scheme reached 10.5%,which is too high for practical use.After coupled control,the 3 D shock structure became“C”shaped distribution along spanwise because of the difference in influence mechanism of negatively bowed blading on different spanwise location.Due to the opposite influence effect of positively and negatively bowed blading,the shock structure in the two different schemes of cascades were different and showed opposite variation trends as aspect ratio increased.
