Design and Performance of a High-Pressure Ratio Turbocharger Compressor Part 2: Experimental Performance

Whitfield, A.; Doyle, M. D. C.; Firth, M R

doi:10.1243/pime_proc_1993_207_021_02

Cited by 4 publications

(3 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One interesting conclusion they pointed out during their studies is the negative pre-whirl setting had higher potential to increase the surge margin than the positive pre-whirl setting. This conclusion is in contrast to the previous studies [281,282,305,355,356,357,360,363] where it was demonstrated the surge limit is improved when the pre-whirl has the same direction as the compressor wheel. To explain this different behavior, the authors paid special attention to the flow distribution imposed by the radial inlet and centripetal vanes of the swirl generator, with low velocities at the center and high velocities at the periphery of the compressor inducer.…”

Section: Pre-whirl Generatorscontrasting

confidence: 99%

See 1 more Smart Citation

Trends and Limits of Two-Stage Boosting Systems for Automotive Diesel Engines

Varnier¹,

Olivier²

View full text Add to dashboard Cite

Internal combustion engines developments are driven by emissions reduction and energetic efficiency increase. To reach the next standards, downsized/downspeeded engines are required to reduce fuel consumption and CO2 emissions. These techniques place an important demand on the charging system and force the introduction of multistage boosting architectures. With many possible arrangements and a large number of parameters to optimize, these architectures present a higher complexity than current systems. The objective of this thesis has thus been to investigate the potential of two-stage boosting architectures to establish, for the particular case of passenger car downsized/downspeeded Diesel engines, the most efficient solutions for achieving the forthcoming CO2 emissions targets.To respond to this objective, an exhaustive literature review of all existing solutions has first been performed to determinate the most promising twostage boosting architectures. Then, a new matching methodology has been defined to optimize the architectures with, on the one hand the development of a new turbine characteristic maps representation allowing straight forward matching calculations and, on the other hand, the development of a complete 0D engine model able to predict, within a reduced computational time, the behavior of any boosting architecture in both steady state and transient operating conditions. Finally, a large parametric study has been carried out to analyze and compare the different architectures on the same base engines, to characterize the impacts of thermo-mechanical limits and turbocharger size on engine performance, and to quantify for different engine development options their potential improvements in terms of fuel consumption, maximum power and fun to drive.As main contributions, the thesis provides new modeling tools for efficient matching calculations and synthesizes the main trends in advanced boosting systems to guide future passenger car Diesel engine development. ResumenLos desarrollos actuales en el campo de los motores de combustión interna alternativos están principalmente motivados por la reducción de las emisiones contaminantes y el aumento de la eficiencia energética. Cumplir con los nuevos estándares para automoción requiere una reducción en el consumo de combustible y en las emisiones de contaminantes, y para ello resulta imprescindible el uso de motores downsized and downspeeded. El empleo de dichas técnicas impone unos requisitos de exigencia elevados al sistema de renovación de la carga y obligan a la introducción de arquitecturas de sobrealimentación multi-etapa. Debido a la gran variedad de configuraciones posibles y al elevado número de parámetros a optimizar, esas arquitecturas presentan una mayor complejidad que los sistemas actuales. Por tanto, el objetivo principal de esta tesis ha sido investigar el potencial de las arquitecturas de sobrealimentación de doble etapa para establecer, en el caso particular de los motores downsized and downspeeded, las soluciones más eficientes qu...

show abstract

Section: Pre-whirl Generatorscontrasting

confidence: 99%

“…With compressor wheel optimization in mind, Whitefield et al [356,357] manufactured in 1993 a special impeller to take full advantage of a positive prewhirl of 25 ¥ . The impeller backsweep was only 7 ¥ and the inducer blade angle at the tip was selected as -50 ¥ to correspond with the minimum relative Mach number.…”

Section: Pre-whirl Generatorsmentioning

confidence: 99%

Trends and Limits of Two-Stage Boosting Systems for Automotive Diesel Engines

Varnier¹,

Olivier²

View full text Add to dashboard Cite

show abstract

“…However, when the diesel engine is operated under a low-power condition, the compressor loses the ability to provide adequate air supply with proper pressure for the diesel engine [6]. To solve this problem, the variable-geometry compressor (VGC [7][8][9][10], including a variable inlet guide vane [11][12][13] and variable-geometry diffuser [14][15][16]), is introduced into the turbocharger in the diesel engine. With the VGC, the operation range and the efficiency of compressor are expanded extensively, particularly under low mass flow rate and high pressure ratio conditions [17].…”

Section: Introductionmentioning

confidence: 99%

A prediction model of compressor with variable-geometry diffuser based on elliptic equation and partial least squares

Li¹,

Yang²,

Wang³

et al. 2018

R. Soc. open sci.

View full text Add to dashboard Cite

To achieve a much more extensive intake air flow range of the diesel engine, a variable-geometry compressor (VGC) is introduced into a turbocharged diesel engine. However, due to the variable diffuser vane angle (DVA), the prediction for the performance of the VGC becomes more difficult than for a normal compressor. In the present study, a prediction model comprising an elliptical equation and a PLS (partial least-squares) model was proposed to predict the performance of the VGC. The speed lines of the pressure ratio map and the efficiency map were fitted with the elliptical equation, and the coefficients of the elliptical equation were introduced into the PLS model to build the polynomial relationship between the coefficients and the relative speed, the DVA. Further, the maximal order of the polynomial was investigated in detail to reduce the number of sub-coefficients and achieve acceptable fit accuracy simultaneously. The prediction model was validated with sample data and in order to present the superiority of compressor performance prediction, the prediction results of this model were compared with those of the look-up table and back-propagation neural networks (BPNNs). The validation and comparison results show that the prediction accuracy of the new developed model is acceptable, and this model is much more suitable than the look-up table and the BPNN methods under the same condition in VGC performance prediction. Moreover, the new developed prediction model provides a novel and effective prediction solution for the VGC and can be used to improve the accuracy of the thermodynamic model for turbocharged diesel engines in the future.

show abstract