Based on the geometrically nonlinear theory of axially extensible elastic rods, the governing equations of post_buckling of a clamped_free rod with variable cross_sections, subjected to a combined load, a concentrated...Based on the geometrically nonlinear theory of axially extensible elastic rods, the governing equations of post_buckling of a clamped_free rod with variable cross_sections, subjected to a combined load, a concentrated axial load P at the free end and a non_uniformly distributed axial load q, are established.By using shooting method, the strong nonlinear boundary value problems are numerically solved. The secondary equilibrium paths and the post_buckling configurations of the rod with linearly varied cross_sections are presented.展开更多
This paper presents the experimental results to understand the performance of moderately loaded high speed single stage transonic axial flow compressor subjected to various configurations of axial extensions of bend s...This paper presents the experimental results to understand the performance of moderately loaded high speed single stage transonic axial flow compressor subjected to various configurations of axial extensions of bend skewed casing treatment with moderate porosity.The bend skewed casing treatment of 33%porosity was coupled with rectangular plenum chamber of depth equal to the slots depth.The five axial extensions of 20%,40%,60%,80%and 100%were used for the experimental evaluations of compressor performance.The main objective was to identify the optimum extension of the casing treatment with reference to rotor leading edge which results in maximum stall margin improvements with minimum loss in the stage efficiency.At each axial extension the compressor performance is distinctive.The improvement in the stall margin was very significant at some axial extensions with 4%–5%penalty in the stage efficiency.The compressors stage shows recovery in terms of efficiency at lower axial extensions of 20%and 40%with increase in the peak stage efficiency.Measurements of flow parameters showed the typical behaviors at near stall flow conditions.Hot wire sensor was placed at the rotor upstream in the tip region to capture the oscillations in the inlet axial and tangential velocities at stall conditions.In the absence of casing treatment the compressor exhibit abrupt stall with very high oscillations in the inlet axial and tangential velocity of the flow.The extents of oscillations reduce with bend skewed casing treatment.Few measurements were also performed in the plenum chamber and salient results are presented in this paper.展开更多
文摘Based on the geometrically nonlinear theory of axially extensible elastic rods, the governing equations of post_buckling of a clamped_free rod with variable cross_sections, subjected to a combined load, a concentrated axial load P at the free end and a non_uniformly distributed axial load q, are established.By using shooting method, the strong nonlinear boundary value problems are numerically solved. The secondary equilibrium paths and the post_buckling configurations of the rod with linearly varied cross_sections are presented.
基金Authors take this opportunity to thank Director,CSIRNAL,for funding the research program through elevenths five year plan and allow publishing the results.
文摘This paper presents the experimental results to understand the performance of moderately loaded high speed single stage transonic axial flow compressor subjected to various configurations of axial extensions of bend skewed casing treatment with moderate porosity.The bend skewed casing treatment of 33%porosity was coupled with rectangular plenum chamber of depth equal to the slots depth.The five axial extensions of 20%,40%,60%,80%and 100%were used for the experimental evaluations of compressor performance.The main objective was to identify the optimum extension of the casing treatment with reference to rotor leading edge which results in maximum stall margin improvements with minimum loss in the stage efficiency.At each axial extension the compressor performance is distinctive.The improvement in the stall margin was very significant at some axial extensions with 4%–5%penalty in the stage efficiency.The compressors stage shows recovery in terms of efficiency at lower axial extensions of 20%and 40%with increase in the peak stage efficiency.Measurements of flow parameters showed the typical behaviors at near stall flow conditions.Hot wire sensor was placed at the rotor upstream in the tip region to capture the oscillations in the inlet axial and tangential velocities at stall conditions.In the absence of casing treatment the compressor exhibit abrupt stall with very high oscillations in the inlet axial and tangential velocity of the flow.The extents of oscillations reduce with bend skewed casing treatment.Few measurements were also performed in the plenum chamber and salient results are presented in this paper.
