Unsteady Total Pressure Field Downstream of an Embedded Stator in a Multistage Axial Flow Compressor

1997 ◽  
Vol 119 (4) ◽  
pp. 985-994 ◽  
Author(s):  
N. Suryavamshi ◽  
B. Lakshminarayana ◽  
J. Prato ◽  
J. R. Fagan
Keyword(s):  
Total Pressure ◽  
High Speed ◽  
Pressure Field ◽  
Axial Flow ◽  
Temporal Variations ◽  
Pressure Probe ◽  
Peak Efficiency ◽  
Axial Flow Compressor ◽  
Multistage Compressors ◽  
Flow Compressor

The results from measurements of the unsteady total pressure field downstream of an embedded stage of a three stage axial flow compressor are presented in this paper. The measurements include area traverses of a high response kulite total pressure probe and a pneumatic five hole probe downstream of stator 2 at the peak efficiency operating point for the compressor. These data indicate that both the shaft-resolved and unresolved fluctuations contribute to the unsteadiness of the total pressure field in multistage compressors. Specifically, regions associated with high levels of unsteadiness and, consequently, high levels of mixing including both the hub and casing end walls and the airfoil wakes have significant levels of shaft resolved and unresolved unsteadiness. Temporal variations of stator exit flow are influenced by both shaft resolved and unresolved unsteadiness distributions. The limitations of state-of-the-art instrumentation for making measurements in moderate and high speed turbomachinery and the decomposition used to analyze these data are also discussed.

scholarly journals The Numerical Simulation of a High-Speed Axial Flow Compressor

1991 ◽  
Author(s):  
Richard A. Mulac ◽  
John J. Adamczyk
Keyword(s):  
Numerical Simulation ◽  
Data Storage ◽  
High Speed ◽  
Axial Flow ◽  
Equation System ◽  
Axial Flow Compressor ◽  
Code Performance ◽  
Recent Developments ◽  
Multistage Compressors ◽  
Flow Compressor

The advancement of high-speed axial flow multistage compressors is impeded by a lack of detailed flow field information. Recent developments in compressor flow modeling and numerical simulation have the potential to provide needed information in a timely manner. This paper, which consists of two parts, will explore this topic. The first part will address the development of a computer program to solve the viscous form of the average-passage equation system for multistage turbomachinery. Programming issues such as in-core versus out-of-core data storage and CPU utilization (parallelization, vectorization, and chaining) will be addressed. Code performance will be evaluated through the simulation of the first four stages of a five stage, high-speed, axial flow compressor on a CRAY Y-MP8/8128 computer. The second part will address the flow physics which can be obtained from the numerical simulation. In particular, an examination of the endwall flow structure will be made, and its impact on blockage distribution assessed.

An Experimental Investigation About the Effect of the Partial Casing Treatment on a Transonic Axial-Flow Compressor Performance Under Inlet Distortion

2012 ◽  
Author(s):  
Maoyi Li ◽  
Wei Yuan ◽  
Xizhen Song ◽  
Yajun Lu ◽  
Zhiping Li ◽  
...  
Keyword(s):  
Total Pressure ◽  
Pressure Ratio ◽  
Axial Flow ◽  
Peak Efficiency ◽  
Stall Margin ◽  
Casing Treatment ◽  
Axial Flow Compressor ◽  
Inlet Distortion ◽  
Flow Compressor ◽  
Total Pressure Ratio

The traditional annulus casing treatment often pays the price of lowered efficiency for improving the stall margin of a compressor under inlet distortion. In view of the unsymmetry of the inlet flow-field of compressors, partial casing treatment was used to control the flow in a transonic axial-flow compressor with arc-skewed-slots deployed at different circumferential positions under inlet distortion. The experimental results indicate that when the partial casing treatment is arranged on the undistorted and distorted sectors, the stall margin is enhanced by 8.02%, with the relative peak efficiency improved simultaneously by 2.143%, compared with the case of solid casing at 98% rotating speed. By contrast, the traditional casing treatment increases the stall-margin by 23.13%, but decreases the relative peak efficiency by 0.752%. By analyzing dynamic and static experimental data, the mechanism underlying the partial casing treatment was also studied in detail here. The disturbances of inlet flow were restrained by annulus casing treatment, nevertheless the total pressure ratio was decreased obviously in the distorted sector. As a result, the stall-margin is improved, but the relative peak efficiency is decreased too. When the partial casing treatment was arranged on the undistortded and distorted sectors, the stall disturbances was thereby restrained. So the stall margin was enhanced. In addition, the total pressure ratio was improved by the partial casing treatment in the distorted and transition sectors, and thus the relative peak efficiency was also increased markedly.

Experimental Investigation of Rotating Stall in a Mismatched Three-Stage Axial Flow Compressor

1989 ◽  
Vol 111 (4) ◽  
pp. 418-425 ◽  
Author(s):  
G. L. Giannissis ◽  
A. B. McKenzie ◽  
R. L. Elder
Keyword(s):  
High Speed ◽  
Measurement Techniques ◽  
Axial Flow ◽  
Fast Response ◽  
Rotating Stall ◽  
Response Measurement ◽  
Stall Inception ◽  
Axial Flow Compressor ◽  
Multistage Compressors ◽  
Flow Compressor

This paper reports on an examination of rotating stall in a low-speed three-stage axial flow compressor operating with various degrees of stage mismatch. The objective of this study was to simulate the mismatching that occurs in high-speed multistage compressors when operating near surge. The study of the stall zones involved the use of fast response measurement techniques. The study clearly shows how stages can operate in an axisymmetric fashion even when heavily stalled, since rotating stall inception requires the stall of more than one stage. The study also compares conditions required for full-span and part-span stall and suggests that the part-span stall structure is more relevant to high-speed multistage compressors.

The Numerical Simulation of a High-Speed Axial Flow Compressor

1992 ◽  
Vol 114 (3) ◽  
pp. 517-527 ◽  
Author(s):  
R. A. Mulac ◽  
J. J. Adamczyk
Keyword(s):  
Numerical Simulation ◽  
Data Storage ◽  
High Speed ◽  
Axial Flow ◽  
Equation System ◽  
Axial Flow Compressor ◽  
Code Performance ◽  
Recent Developments ◽  
Multistage Compressors ◽  
Flow Compressor

The advancement of high-speed axial flow multistage compressors is impeded by a lack of detailed flow field information. Recent developments in compressor flow modeling and numerical simulation have the potential to provide needed information in a timely manner. This paper, which consists of two parts, will explore this topic. The first part will address the development of a computer program to solve the viscous form of the average-passage equation system for multistage turbomachinery. Programming issues such as in-core versus out-of-core data storage and CPU utilization (parallelization, vectorization, and chaining) will be addressed. Code performance will be evaluated through the simulation of the first four stages of a five-stage, high-speed, axial flow compressor on a CRAY Y-MP8/8128 computer. The second part will address the flow physics, which can be obtained from the numerical simulation. In particular, an examination of the end-wall flow structure will be made, and its impact on blockage distribution assessed.

Aspirating Probe Measurements of the Unsteady Total Temperature Field Downstream of an Embedded Stator in a Multistage Axial Flow Compressor

1996 ◽  
Author(s):  
N. Suryavamshi ◽  
B. Lakshminarayana ◽  
J. Prato
Keyword(s):  
Axial Flow ◽  
Pressure Data ◽  
Peak Efficiency ◽  
Axial Flow Compressor ◽  
Composite Flow ◽  
Total Temperature ◽  
Temperature And Pressure ◽  
Flow Compressor ◽  
Isentropic Efficiency ◽  
Probe Measurements

The results from the area traverse measurements of the unsteady total temperature using a high response aspirating probe downstream of the second stator of a three stage axial flow compressor are presented. The measurements were conducted at the peak efficiency operating point. The unsteady total temperature data is resolved into deterministic and unresolved components. Hub and casing regions have high levels of unsteadiness and consequently high levels of mixing. These regions have significant levels of shaft resolved and unresolved unsteadiness. Comparisons are made between the total temperature and the total pressure data to examine the rotor 2 wake characteristics and the temporal variation of the stator exit flow. Isentropic efficiency calculations at the midpitch location show that there is about a 4% change in the algebraically averaged efficiency across the blades of the second rotor and if all the rotor 2 blades were behaving as a “best” blade, the improvement in efficiency would be about 1.3%. An attempt is made to create a composite flow field picture by correlating the unsteady velocity data with temperature and pressure data.

Stall cell blockage in a high-speed multistage axial-flow compressor

1990 ◽  
Author(s):  
STEVEN GORRELL ◽  
WILLIAM COPENHAVER ◽  
WALTER O'BRIEN
Keyword(s):  
High Speed ◽  
Axial Flow ◽  
Axial Flow Compressor ◽  
Flow Compressor

scholarly journals Development of a PVDF Sensor Array for Measurement of the Dynamic Pressure Field of the Blade Tip in an Axial Flow Compressor

Sensors ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1404
Author(s):  
Jiqing Cong ◽  
Jianping Jing ◽  
Changmin Chen
Keyword(s):  
Frequency Response ◽  
Field Measurement ◽  
Sensor Array ◽  
Pressure Field ◽  
Dynamic Pressure ◽  
Axial Flow ◽  
Actual Measurement ◽  
Axial Flow Compressor ◽  
Blade Tip ◽  
Flow Compressor

Tip clearance flow in axial flow compressor is unavoidable and responsible for pressure losses and noise generation and influences the stability of the compressor. However, necessary flow measurement in the blade tip region is a great challenge due to the small gap width as well as the structure limitation. In this paper, a polyvinylidene fluoride (PVDF) piezoelectric-film sensor array is developed to capture the dynamic pressure field over the blade tip in an axial flow compressor. The PVDF sensor array with 40 evenly distributed sensing points is fabricated directly on a 30 μm thick aluminum-metalized polarized PVDF film through photolithography. Dynamic calibration of the sensor is accomplished using acoustic source as excitation and a microphone as a reference. The test pressure range is up to 3.5 kPa and the sampling frequency is 20 kHz. The sensor presents a high signal-to-noise ratio and good consistency with the reference microphone. Sensitivity, frequency response, linearity, hysteresis, repeatability as well as the influence of temperature are also investigated through the calibration apparatus. The calibration gives credence to the relevance and reliability of this sensor for the application in dynamic pressure field measurement. The sensor is then applied to an actual measurement in a compressor. The output of the PVDF sensor array is also compared with the results of common pressure transducers, and the features of the dynamic pressure filed are discussed. The results indicate that the PVDF sensor array is capable of the dynamic pressure field measurement over the blade tip, and superior to the conventional approaches in installation, spatial resolution, frequency response, and cost. These advantages indicate its potential broad application in pressure measurement, especially for the complex spatial surface or thin-walled structure, such as the blade surface and the thin casing wall of the compressor.

Compound Piston-and-Turbine Engines

1959 ◽  
Vol 81 (3) ◽  
pp. 259-264 ◽  
Author(s):  
A. L. London
Keyword(s):  
Gas Turbine ◽  
High Speed ◽  
Axial Flow ◽  
Turbine Engines ◽  
Exhaust Gas ◽  
Prime Mover ◽  
Axial Flow Compressor ◽  
Flow Compressor

The prime-mover combination of piston-and-cylinder components with a high-speed exhaust-gas turbine and, in some cases, a centrifugal or axial-flow compressor has assumed a variety of forms. Progress in the development of some of the more notable members of this family of compound engines is presented.

Effect of Turbulence Model on the Prediction of Performance and Span-Wise Mixing in High-Speed Highly-Loaded Multi-Stage Axial-Flow Compressor

2019 ◽  
Author(s):  
Takashi Goto ◽  
Tetsuya Oshio ◽  
Naoki Tani ◽  
Mizuho Aotsuka ◽  
Guillaume Pallot ◽  
...  
Keyword(s):  
Flow Field ◽  
Turbulence Model ◽  
High Speed ◽  
Axial Flow ◽  
Weno Scheme ◽  
Axial Flow Compressor ◽  
Multi Stage ◽  
Radial Profiles ◽  
Flow Compressor ◽  
Highly Loaded

Abstract Despite significant advancements in computational power and various numerical modeling in past decades, flow simulation of a multi-stage axial-flow compressor is still one of the most active areas of research, for it is the critical component in engine performance and operability, and there are so many elements that need to be looked into to predicting correct matching of the stages and accurate flow distribution inside the machine. Modeling unsteadiness, both deterministic and random types, and real geometries are among the most important features to be considered in such prediction. The authors have conducted in their previous studies a series of unsteady RANS (URANS) simulations of a 6.5-stage high-speed highly-loaded axial-flow compressor, and explored many unsteady effects as well as effects of real geometries such as Variable Stator Vane (VSV) clearance and inter-stage seal leakage flow on the compressor performance. However, all the analyses failed to predict correct stage matching, total pressure and temperature radial profiles, or mass-flow with adequate accuracies. In the present study, an Improved Delayed Detached Eddy Simulation (IDDES) with SST k-omega model is applied to the simulation of the same compressor configuration at aerodynamic design point. Fifth-order WENO scheme is employed for improved spatial accuracy to suppress significant increase in mesh size. Total number of mesh points are over 400 million for 1/10th sector model. Computations are ensemble averaged for 20 sector passage. Computed overall performance and flow field are compared with the compressor rig test data. The predictions of inter-stage total temperature radial profiles are noticeably improved over the URANS with the same mesh, discretization scheme and eddy turbulence model. Good comparison with the rig data indicates the current simulation is properly capturing the span-wise mixing phenomena. Unsteady flow field are compared between IDDES and URANS to locate the cause for the enhanced mixing. It is shown that components of Reynolds stress responsible for radial diffusion and anisotropic features are intensified in the tip leakage vortex at the rotor exit for the IDDES.

Sign in / Sign up

Export Citation Format

Share Document