Aerodynamic Performance of Small Turbocharger Compressors

Automotive turbocharger compressors are characterized by small dimensions. These small dimensions make detailed measurements of the flow field inside the compressor very challenging. However, it is very important to investigate and understand the aerodynamic performance of these machines in order to enhance the ability to improve their performance. The present paper aims at investigating the aerodynamic performance of the individual compressor components and the interaction between these components. The aerodynamic performance of a GT1749V 70 Trim turbocharger compressor is investigated with particular attention to measurements of the static pressure distribution at the inlet and outlet of the diffuser. A 1D-model is developed to solve the conservation equations along the streamlines inside the diffuser with the measured static pressure distributions as boundary conditions. The loss coefficients of the impeller, the diffuser, and the volute as well as the slip factor of the impeller are estimated from the experimental data with the help of the 1D-model developed in the present work. The model is also validated using available experimental data from a large radial compressor and shows a good agreement with the experimental results.

Effect of Boundary Layer Suction on Aerodynamic Performance of High-Turning Compressor Cascade

Volume 6A: Turbomachinery ◽

10.1115/gt2013-94907 ◽

2013 ◽

Author(s):

Longxin Zhang ◽

Shaowen Chen ◽

Hao Xu ◽

Jun Ding ◽

Songtao Wang

Keyword(s):

Experimental Data ◽

Boundary Layer ◽

Experimental Studies ◽

Aerodynamic Performance ◽

Parameter Distribution ◽

Compressor Cascade ◽

Boundary Layer Suction ◽

End Wall ◽

Low Speed Wind Tunnel ◽

Compared with suction slots, suction holes are (1) flexible in distribution; (2) alterable in size; (3) easy to fabricate and (4) high in strength. In this paper, the numerical and experimental studies for a high turning compressor cascade with suction air removed by using suction holes in the end-wall at a low Mach numbers are carried out. The main objective of the investigation is to study the influence of different suction distributions on the aerodynamic performance of the compressor cascade and to find a better compound suction scheme. A numerical model was first made and validated by comparing with the experimental results. The computed flow visualization and exit parameter distribution showed a good agreement with experimental data. Second, the model was then used to simulate the influence of different suction distributions on the aerodynamic performance of the compressor cascade. A better compound suction scheme was obtained by summarizing numerical results and tested in a low speed wind tunnel. As a result, the compound suction scheme can be used to significantly improve the performance of the compressor cascade because the corner separation gets further suppressed.

2003 International Electronic Packaging Technical Conference and Exhibition, Volume 2 ◽

Experiments and Modeling of the Hydraulic Resistance of In-Line Square Pin Fin Heat Sinks With Top By-Pass Flow

10.1115/ipack2003-35268 ◽

2003 ◽

Author(s):

Mario Urdaneta ◽

Alfonso Ortega ◽

Russel V. Westphal

Keyword(s):

Static Pressure ◽

Heat Sinks ◽

Pressure Measurements ◽

Pin Fin ◽

Pressure Distributions ◽

Full Development ◽

Background Data ◽

Physical Insight ◽

Loss Coefficients ◽

Insight Into

Extensive experiments were performed aimed at obtaining physical insight into the behavior of in-line pin fin heat sinks with pins of square cross-section. Detailed pressure measurements were made inside an array of square pins in order to isolate the inlet, developing, fully developed, and exit static pressure distributions as a function of row number. With this as background data, overall pressure drop was measured for a self-consistent set of aluminum heat sinks in side inlet side exit flow, with top clearance only. Pin heights of 12.5 mm, 17.5 mm, and 22.5 mm, pin pitch of 3.4 mm to 6.33 mm, and pin thickness of 1.5 mm, 2 mm and 2.5mm were evaluated. Base dimensions were kept fixed at 25 × 25 mm. In total, 20 aluminum heat sinks were evaluated. A “two-branch by-pass model” was developed, by allowing inviscid acceleration of the flow in the bypass section, and using pressure loss coefficients obtained under no bypass conditions in the heat sink section. The experimental data compared well to the proposed hydraulic models. Measurements in the array of pins showed that full development of the flow occurs after nine rows, thus indicating that none of the heat sinks tested could be characterized as fully-developed.

Numerical Simulation of Rotor in Hover and Forward Flight

MATEC Web of Conferences ◽

10.1051/matecconf/201817903011 ◽

2018 ◽

Vol 179 ◽

pp. 03011

Author(s):

Qinghe Zhao

Keyword(s):

Experimental Data ◽

Numerical Simulation ◽

Flow Field ◽

Moving Grid ◽

Steady State Flow ◽

Forward Flight ◽

Numerical Simulation Result ◽

Structured Grid ◽

Pressure Distributions ◽

The flow around rotor is numerical simulated in hover and forward flight based on multi-structured grid. In hover the flow field can be transformed into a steady-state flow field in the rotating coordinate system. The experimental data of Caradonna and Tung rotor is used to verify the numerical simulation result. The numerical results compare well with the experimental data for both non-lifting and lifting cases. Non-lifting forward flight is simulated and the prediction capabilities have been validated through the ONERA two-blade rotor. The pressure distributions of different positions under different azimuth angles are compared, which is in good agreement with the experimental data. There is unsteady shock wave when forward flight. Dual-time method is used to obtain unsteady flow field with rigid moving grid in the inertial system.

Ligand Redistribution Equilibria in Aqueous Fluoroberyllate Solutions

Zeitschrift für Naturforschung B ◽

10.1515/znb-1998-1110 ◽

1998 ◽

Vol 53 (11) ◽

pp. 1294-1300 ◽

Cited By ~ 11

Author(s):

Michael Schmidt ◽

Hubert Schmidbaur

Keyword(s):

Experimental Data ◽

Ligand Exchange ◽

Room Temperature ◽

Chemical Shifts ◽

Equilibrium Constants ◽

Individual Species ◽

Ph Values ◽

Exchange Processes ◽

The Individual ◽

The composition of aqueous fluoroberyllate solutions has been studied by 9Be and 19F NMR spectroscopy for various ratios of the beryllium and fluorine concentrations, and at different pH values. The equilibrium constants have been determined for the ligand exchange processes, which involve the species [Be(OH2)4]2+, [BeF(OH2)3]+, [BeF2(OH2)2], [BeF3(OH2)]- , and [BeF4]2-. These equilibria are shifted towards [BeF4]2- at high pH. No polynuclear fluoroberyllates have been detected. The fluoride exchange between the individual species is slow on the NMR time scale at room temperature, and separate sharp signals with the expected multiplicity are therefore recorded. Calculated 9Be chemical shifts are in good agreement with experimental data.

Study on Numerical Simulation Method of Aerodynamic Performance of High-Speed Train on Bridge

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.376.312 ◽

2013 ◽

Vol 376 ◽

pp. 312-316 ◽

Author(s):

Chao Qun Xiang ◽

Wen Hua Guo ◽

Jia Wen Zhang

Keyword(s):

Static Pressure ◽

Aerodynamic Performance ◽

Dynamic Mesh ◽

Positive Pressure ◽

Aerodynamic Coefficients ◽

Force Coefficient ◽

Rolling Moment ◽

Velocity Magnitude ◽

Pressure Distributions ◽

Mesh Method

The dynamic mesh method that could simulate the actual moving of train was used to calculate the aerodynamic coefficients of train on bridge with wind barriers of various heights, and the static pressure distributions around the train body and velocity magnitude distributions were analyzed, the results computed by dynamic mesh method were compared with that computed by traditional static mesh method. The results show that the aerodynamic coefficients of train and flow field characteristics computed by the two methods agree well under the configuration without wind barriers. However, there is considerable difference between the results computed by the two methods with the installation of wind barriers. It is found that the dynamic mesh method is more reasonable to simulate the aerodynamic coefficients of train with wind barriers by analysis of the contour of static pressure distributions and velocity magnitude distributions. The wind barriers effectively decrease the positive pressure on windward train body and negative pressure on train roof, mainly reduce the side force coefficient, lift force coefficient, rolling moment coefficient. Therefore, the aerodynamic performance of train on bridge under crosswind is improved.

The Interaction Between the Impeller and Casing in a Small-Size Turbo-Compressor

Volume 2: Symposia and General Papers, Parts A and B ◽

10.1115/fedsm2002-31179 ◽

2002 ◽

Author(s):

D.-W. Kim ◽

Youn J. Kim

Keyword(s):

Static Pressure ◽

Stokes Equations ◽

Three Dimensional ◽

Reference Method ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Pressure Distributions ◽

Loss Coefficients ◽

Compressible Turbulent Flow ◽

Turbo Compressor

The effects of casing shape on the performance and the interaction between the impeller and casing in a small-size turbo-compressor are investigated. Numerical analysis is conducted for the compressor with circular and single volute casings from inlet to discharge nozzle. In order to predict the flow pattern inside the entire impeller, vaneless diffuer and casing, calculations with multiple frames of reference method between the rotating and stationery parts of the domain are carried out. For compressible turbulent flow fields, the continuity and three-dimensional time-averaged Navier-Stokes equations are employed. To evaluate the performance of two types of casings, the static pressure and loss coefficients are obtained with various flow rates. Also, static pressure distributions around casings are studied for different casing shapes, which are very important to predict the distribution of radial load. To prove the accuracy of numerical results, measurements of static pressure around casing and pressure difference between the inlet and outlet of the compressor are performed for the circular casing. Comparison of these results between the experimental and numerical analyses are conducted, and reasonable agreement is obtained.

The Use of Surface Static Pressure Data as a Diagnostic Tool in Multistage Compressor Development

Journal of Turbomachinery ◽

10.1115/1.3262057 ◽

1987 ◽

Vol 109 (1) ◽

pp. 123-129 ◽

Cited By ~ 2

Author(s):

H. D. Weingold ◽

R. F. Behlke

Keyword(s):

Data Analysis ◽

Static Pressure ◽

Development Phase ◽

Pressure Data ◽

Flow Angle ◽

Pressure Distributions ◽

Analysis Technique ◽

Multistage Compressor ◽

Engine Testing ◽

The Individual

A technique has been developed to analyze static pressure distributions obtained from the surfaces of stators in a multistage compressor to determine incident Mach number and flow angle and the turning and streamtube contraction for the individual stator sections. This data analysis technique permits this nonintrusive type of pressure measurement to be used to optimize the design of stator airfoils during the development phase of a multistage compressor and, in the development of analytic compressor representations, to segregate rotor and stator performance and to improve the modeling of endwall blockage. The value of this technique has been demonstrated in cascade testing of compressor airfoils, in single-stage and three-stage rig testing, and in engine testing.

Application of the Surge Model to Radial Compressor System Cycle Optimization

Volume 6C: Turbomachinery ◽

10.1115/gt2013-94222 ◽

2013 ◽

Author(s):

Viktor Kilchyk ◽

Ahmed Abdelwahab ◽

Andrew Rosinski

Keyword(s):

Experimental Data ◽

Open Loop ◽

Time Dependent ◽

Design Parameters ◽

Radial Compressor ◽

Lumped Parameter ◽

Compressor Design ◽

Compressor Efficiency ◽

Good Agreement ◽

Variable Coupling

Surge avoidance and minimization of power consumption in the design of a radial compressor cycle requires a solution to the complex, time-dependent problem of implicit variable coupling. To solve this problem, a modified lumped parameter surge model was developed and tested using experimental data. The model was expanded to include open-loop, time-dependent (periodic) boundary conditions with added equations representing the effects of heat transfer and flow compressibility. Comparison with experimental data showed good agreement with model-predicted behavior. The developed model of the compressor system was analyzed with respect to the main compressor design parameters. Sensitivity of the compressor system to the valve timing and resistance, wheel diameter, and inertia was also examined. It was demonstrated that the mass flow rate-averaged, or power-averaged compressor efficiency was improved by over 3 percent using the optimum impeller diameter.

Mistuned Forced Response Predictions of an Embedded Rotor in a Multistage Compressor

Journal of Turbomachinery ◽

10.1115/1.4032164 ◽

2016 ◽

Vol 138 (6) ◽

Cited By ~ 15

Author(s):

Fanny M. Besem ◽

Robert E. Kielb ◽

Paul Galpin ◽

Laith Zori ◽

Nicole L. Key

Keyword(s):

Experimental Data ◽

Steady State ◽

Aerodynamic Performance ◽

Forced Response ◽

Response Analysis ◽

Data Set ◽

Multistage Compressor ◽

The Individual ◽

Decoupled Method ◽

Tremendous Impact

This paper covers a comprehensive forced response analysis conducted on a multistage compressor and compared with the largest forced response experimental data set ever obtained in the field. The steady-state aerodynamic performance and stator wake predictions compare well with the experimental data, although losses are underestimated. Coupled and uncoupled unsteady simulations are conducted on the stator–rotor configuration. It is shown that the use of a decoupled method for forced response cannot yield accurate results for cases with strong inter-row interactions. The individual and combined contributions of the upstream and downstream stators are also assessed. The downstream stator is found to have a tremendous impact on the forced response predictions due to the constructive interactions of the two stator rows. Finally, predicted mistuned blade amplitudes are compared to mistuned experimental data. The average amplitudes match the experiments very well, while the maximum response amplitude is underestimated.

Pressure Distributions in Manifolds with Return Ducts

Journal of Mechanical Engineering Science ◽

10.1243/jmes_jour_1972_014_039_02 ◽

1972 ◽

Vol 14 (5) ◽

pp. 319-327

Author(s):

G. R. Kimber ◽

M. A. Hollingsworth

Keyword(s):

Static Pressure ◽

Air Flow ◽

Design Stage ◽

Frictional Losses ◽

Pressure Distributions ◽

Good Agreement ◽

The Ideal ◽

Inlet Duct

Longitudinal static pressure distributions in air flow have been measured in manifolds with untapered inlet and outlet ducts, closed at one end and interconnected by a large number of identical ports. The transfer of air through these ports causes the static pressure to rise towards the closed end of the inlet duct, although friction reduces this rise to about 50 per cent of its ideal value. For very long ducts the pressure initially decreases near the inlet end. In the outlet duct the ideal drop in pressure from the closed end is increased by about 15 per cent. Theoretical distributions in good agreement with measurements are obtained assuming constant values for the frictional losses for each configuration and meaningful predictions may be made at the design stage since pressure distributions are found to be relatively insensitive to these values.