Effects of blade bowing on the performance of a high pressure-ratio turbocharger centrifugal compressor with self-recirculation casing treatment

Large feasible operation range is a challenge for high pressure ratio centrifugal compressor of turbocharger in vehicle engine. Self-Recycling-Casing-Treatment (SRCT) is a widely used flow control method to enlarge the range for this kind of compressor. This paper investigates the influence of symmetrical/asymmetrical SRCT (ASRCT) on the stability of a high pressure ratio centrifugal compressor by experimental testing and numerical simulation. Firstly, the performance of the compressor with/without SRCT is tested is measured investigate the influence of flow distortion on the stability of compressor as well as the numerical method validation. Then detailed flow field investigation is conducted by experimental measurement and the numerical method to unveil the reasons for stability enhancement by symmetrical/asymmetrical SRCT. Results show that static pressure distortion at impeller outlet caused by the volute can make passages be confronted with flow distortion less stable than others because of their larger positive slope of T-S pressure ratio performance at small flow rate. SRCT can depress the flow distortion and reduce the slope by non-uniform recycling flow rate at impeller inlet. Moreover, ASRCT can redistribute the recycling flow in circumferential direction according to the asymmetric geometries. When the largest recycling flow rate is imposed on the passage near the distorted static pressure, the slope will be the most effectively reduced. Therefore, the stability is effectively enhanced by the optimized recycling flow device.

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Stability Improvement of High-Pressure-Ratio Turbocharger Centrifugal Compressor by Asymmetric Flow Control: Part II—Non-Axisymmetric Self Recirculation Casing Treatment

Volume 7: Turbomachinery, Parts A, B, and C ◽

10.1115/gt2010-22582 ◽

2010 ◽

Cited By ~ 7

Author(s):

Xinqian Zheng ◽

Yangjun Zhang ◽

Mingyang Yang ◽

Takahiro Bamba ◽

Hideaki Tamaki

Keyword(s):

High Pressure ◽

Flow Control ◽

Centrifugal Compressor ◽

Control Method ◽

Pressure Ratio ◽

Leading Edge ◽

Asymmetric Flow ◽

Casing Treatment ◽

High Pressure Ratio ◽

Compressor Performance

This is the Part II of a two-part paper involving the development of asymmetric flow control method to widen the operating range of a turbocharger centrifugal compressor with high-pressure-ratio. Non-axisymmetric Self Recirculation Casing Treatment (SRCT) as an instance of asymmetric flow control method is presented. Experimental and numerical methods were used to investigate the impact of non-axisymmetric SRCT on surge point of the centrifugal compressor. Firstly, the influence of the geometry of a symmetric SRCT on the compressor performance was studied by means of numerical simulation. The key parameter of the SRCT was found to be the distance from the main blade leading edge to the rear groove (Sr). Next, several arrangements of a non-axisymmetric SRCT were designed, based on flow analysis presented in Part I. Then, a series of experiments was carried out to analyze the influence of non-axisymmetric SRCT on the compressor performance. Results show that the non-axisymmetry SRCT has certain influence on performance and has a larger potential for stability improvement than the traditional symmetric SRCT. For the investigated SRCT, the surge flow rate of the compressor with the non-axisymmetric SRCT is about 10% lower than that of the compressor with symmetric SRCT. The largest surge margin (smallest surge flow rate) can be obtained when the phase of the largest Sr is coincident with the phase of the minimum static pressure in the vicinity of the leading edge of the splitter blades.

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Stability Improvement of High-Pressure-Ratio Turbocharger Centrifugal Compressor by Asymmetrical Flow Control—Part II: Nonaxisymmetrical Self-Recirculation Casing Treatment

Journal of Turbomachinery ◽

10.1115/1.4006637 ◽

2012 ◽

Vol 135 (2) ◽

Cited By ~ 26

Author(s):

Xinqian Zheng ◽

Yangjun Zhang ◽

Mingyang Yang ◽

Takahiro Bamba ◽

Hideaki Tamaki

Keyword(s):

High Pressure ◽

Flow Control ◽

Flow Rate ◽

Centrifugal Compressor ◽

Control Method ◽

Pressure Ratio ◽

Leading Edge ◽

Casing Treatment ◽

High Pressure Ratio ◽

Compressor Performance

This is part II of a two-part paper involving the development of an asymmetrical flow control method to widen the operating range of a turbocharger centrifugal compressor with high-pressure ratio. A nonaxisymmetrical self-recirculation casing treatment (SRCT) as an instance of asymmetrical flow control method is presented. Experimental and numerical methods were used to investigate the impact of nonaxisymmetrical SRCT on the surge point of the centrifugal compressor. First, the influence of the geometry of a symmetric SRCT on the compressor performance was studied by means of numerical simulation. The key parameter of the SRCT was found to be the distance from the main blade leading edge to the rear groove (Sr). Next, several arrangements of a nonaxisymmetrical SRCT were designed, based on flow analysis presented in part I. Then, a series of experiments were carried out to analyze the influence of nonaxisymmetrical SRCT on the compressor performance. Results show that the nonaxisymmetrical SRCT has a certain influence on the performance and has a larger potential for stability improvement than the traditional symmetric SRCT. For the investigated SRCT, the surge flow rate of the compressor with the nonaxisymmetrical SRCTs is about 10% lower than that of the compressor with symmetric SRCT. The largest surge margin (smallest surge flow rate) can be obtained when the phase of the largest Sr is coincident with the phase of the minimum static pressure in the vicinity of the leading edge of the splitter blades.

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Improvement in the performance of a high-pressure-ratio turbocharger centrifugal compressor by blade bowing and self-recirculation casing treatment

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407013502328 ◽

2013 ◽

Vol 228 (1) ◽

pp. 73-84 ◽

Cited By ~ 11

Author(s):

Xinqian Zheng ◽

Chuanjie Lan

Keyword(s):

High Pressure ◽

Centrifugal Compressor ◽

Pressure Ratio ◽

Casing Treatment ◽

High Pressure Ratio

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Effect of Self-Recirculation-Casing Treatment on High Pressure Ratio Centrifugal Compressor

Journal of Propulsion and Power ◽

10.2514/1.b35438 ◽

2016 ◽

Vol 32 (3) ◽

pp. 602-610 ◽

Cited By ~ 8

Author(s):

Mingyang Yang ◽

Ricardo Martinez-Botas ◽

Yangjun Zhang ◽

Xinqian Zheng

Keyword(s):

High Pressure ◽

Centrifugal Compressor ◽

Pressure Ratio ◽

Casing Treatment ◽

High Pressure Ratio

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Development of a Very High Pressure Ratio Single Stage Centrifugal Compressor

International Review on Modelling and Simulations (IREMOS) ◽

10.15866/iremos.v8i3.6020 ◽

2015 ◽

Vol 8 (3) ◽

pp. 347

Author(s):

Valeriu Dragan ◽

Ion Malael ◽

Bogdan Gherman

Keyword(s):

High Pressure ◽

Centrifugal Compressor ◽

Pressure Ratio ◽

Single Stage ◽

High Pressure Ratio ◽

Very High

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Effect of Recirculation Device With Counter Swirl Vane on Performance of High Pressure Ratio Centrifugal Compressor

Volume 7: Turbomachinery, Parts A, B, and C ◽

10.1115/gt2011-45360 ◽

2011 ◽

Cited By ~ 1

Author(s):

Hideaki Tamaki

Keyword(s):

High Pressure ◽

Mach Number ◽

Flow Rate ◽

Centrifugal Compressor ◽

Pressure Ratio ◽

Negative Slope ◽

Tip Leakage Flow ◽

Recirculation Flow ◽

Operating Range ◽

High Pressure Ratio

Centrifugal compressors used for turbochargers need to achieve a wide operating range. The author has developed a high pressure ratio centrifugal compressor with pressure ratio 5.7 for a marine use turbocharger. In order to enhance operating range, two different types of recirculation devices were applied. One is a conventional recirculation device. The other is a new one. The conventional recirculation device consists of an upstream slot, bleed slot and the annular cavity which connects both slots. The new recirculation device has vanes installed in the cavity. These vanes were designed to provide recirculation flow with negative preswirl at the impeller inlet, a swirl counterwise to the impeller rotational direction. The benefits of the application of both of the recirculation devices were ensured. The new device in particular, shifted surge line to a lower flow rate compared to the conventional device. This paper discusses how the new recirculation device affects the flow field in the above transonic centrifugal compressor by using steady 3-D calculations. Since the conventional recirculation device injects the flow with positive preswirl at the impeller inlet, the major difference between the conventional and new recirculation device is the direction of preswirl that the recirculation flow brings to the impeller inlet. This study focuses on two effects which preswirl of the recirculation flow will generate. (1) Additional work transfer from impeller to fluid. (2) Increase or decrease of relative Mach number. Negative preswirl increases work transfer from the impeller to fluid as the flow rate reduces. It increases negative slope on pressure ratio characteristics. Hence the recirculation flow with negative preswirl will contribute to stability of the compressor. Negative preswirl also increases the relative Mach number at the impeller inlet. It moves shock downstream compared to the conventional recirculation device. It leads to the suppression of the extension of blockage due to the interaction of shock with tip leakage flow.

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