A new method for rapid shock loss evaluation and reduction for the optimization design of a supersonic compressor cascade

Abstract

A one-dimensional analytical shock loss prediction method was proposed to tailor the shock system, i.e. the strength of the first and second passage shock, and reduce the shock loss in a supersonic cascade. To develop the one-dimensional analytical model, the shock system in a supersonic cascade was divided into four processes which can be seen in most supersonic compressor cascade, i.e. the flow upstream the extending-external shock, the flow between the extendingexternal shock and the first passage shock, the accelerating flow from the first passage shock to the second passage shock, and the flow downstream of the second passage shock. Based on some flow assumptions and experimental empirical correlations, the complex flows, containing the shock system, in the blade passage of a supersonic compressor cascade could be described with one-dimensional relationships, which can be used to predict shock losses along the flow passage rapidly and determine the shock system improving direction for achieving lower shock loss while keeping the same cascade static pressure ratio. In order to validate the one-dimensional analytical method, the shock system of two supersonic cascades ARL-SL19 and DLR-PAV-1.5 are modified based on the analysis of the model. The modified cascades achieved about 29% and 25% reduction of shock loss at redesign point compared with baseline cascades, respectively.

Accurate 2-D Modelling of Transonic Compressor Cascade Aerodynamics

“…Detailed experimental and numerical results are presented in other papers. For example, the experimental results reported in [12] have been used in [6] for the validation of a one-dimensional analytical shock loss model for optimizing the shock structure in a supersonic cascade at various operating conditions.…”

“…In [5], another numerical analysis of SWBLI in transonic/supersonic axial flow compressor cascade was performed, showing the results of various turbulence models. A one-dimensional analytical shock loss model was proposed in [6] for optimizing the shock structure in a supersonic cascade. The analytical prediction model was validated by comparing the results against the experimental data and the shock system of two supersonic cascades, which were subsequently optimized.…”

Supersonic Compressor Cascade Shape Optimization under Multiple Inlet Mach Operating Conditions

“…The improvement in the loss coefficient at Mach 1.45 of 26.4% exceeded 25% (obtained by [2]) for the DLR-PAV-1.5 cascade at the same inlet Mach number, despite the higher computational cost of the algorithm adopted in [2]. A greater enhancement (25.5%) was recorded at Mach 1.58 compared to the 20% achieved by [3] at the same Mach number with the ARL-SL19 cascade. The profile was parametrized only for the first half of the camberline without limiting the performance enhancement, confirming its primary relevance in supersonic compressor profiles.…”

“…The ARL-SL19 cascade, investigated by Schreiber and Starken in [8] and by Liu in [3], is a state-of-the-art geometry for supersonic cascade design. In the present study, it was taken as the baseline to implement shape modification so as to enhance cascade performances.…”

“…In [2], a multi-objective optimization of a 2D S-shaped supersonic profile, operating at a unique incidence condition, was conducted using a Kriging-assisted evolutionary algorithm in order to minimize total pressure losses and to maximize the pressure ratio. In [3,4], one-dimensional analytical shock-loss models were developed to predict overall total pressure losses. Upon these models, optimizations were conducted to reduce losses on two baseline geometries, acting on profile shape and thickness distribution.…”