Turbocharger Efficiencies in Pulsating Exhaust Gas Flow

Aymanns, Richard; Scharf, Johannes; Uhlmann, Tolga; Pischinger, Stefan

doi:10.1007/s38313-012-0198-2

Cited by 10 publications

(6 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Equation (8) shows the thermal dimensionless parameter d thermal . This is the ratio between the time needed to change the turbine housing temperature and the time period of system oscillation.…”

Section: Dimensionless Parametersmentioning

confidence: 99%

“…This is problematic in the case of 1D engine modelling as it means that specific values relating to the housing and mechanical inertia are required. Hence, it is proposed to reprocess the data as a function of the non-dimensional parameters proposed in equations (8) and (9). Figure 7 depicts different aspects of the dynamic response in relation to the dimensionless parameters.…”

Section: Non-dimensional Parametersmentioning

confidence: 99%

“…8 Further investigations have broken down the turbine element and shown that the impeller performance can be approximated to quasi-steady models, [9][10][11][12] but the accumulation of mass in-volute cannot. 8,13 Similar dynamic characteristics have been observed for wastegated, variable-geometry and multi-entry turbines. [14][15][16][17][18] Though specialist facilities are being proposed to better measure the transient performance of turbochargers under pulsating conditions, these are often limited by measurement capabilities.…”

Section: Introductionmentioning

confidence: 99%

“…Similar results were also found using a CFD simulation method. 8 Further investigations have broken down the turbine element and shown that the impeller performance can be approximated to quasi-steady models, [9][10][11][12] but the accumulation of mass in-volute cannot. 8,13 Similar dynamic characteristics have been observed for wastegated, variable-geometry and multi-entry turbines.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Dimensionless quantification of small radial turbine transient performance

Deng

Pennycott

Zhang

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part D:

View full text Add to dashboard Cite

Turbochargers are inherently dynamic devices, comprising internal flow volumes, mechanical inertias and thermal masses. When operating under transient conditions within an engine system, these dynamics need to be better understood. In this paper, a new non-dimensional modelling approach to characterise the turbocharger is proposed. Two new dimensionless quantities are defined with respect to mechanical and thermal transient behaviour, which are used in conjunction with the Strouhal number for flow transients. The modelling approach is applied to a small wastegated turbocharger and validated against experimental results. The model is used to simulate the turbocharger mass flow rate, turbine housing temperature and shaft speed responses to different excitation frequencies for different sizes of turbine. The results highlight the influence of turbocharger size on the dynamic behaviour of the system, which is particularly marked for the turbine housing temperature. At certain frequency ranges, the system behaviour is quasi-steady, allowing modelling through static maps in these operating regions. Outside these ranges, however, transient elements play a more important role. The simulation study shows that the proposed dimensionless parameters can be used to normalise the influence of turbine size on the dynamic response characteristics of the system. The model and corresponding dimensionless parameters can be applied in future simulation studies as well as for turbocharger matching in industry.

show abstract

Section: Dimensionless Parametersmentioning

confidence: 99%

Section: Non-dimensional Parametersmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Dimensionless quantification of small radial turbine transient performance

Deng

Pennycott

Zhang

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part D:

View full text Add to dashboard Cite

show abstract

“…In the past few years, the turbine unsteady behaviour under pulsating conditions were investigated and impact of the pulse frequencies and amplitudes on the turbine performance were analysed. 15–18 Recent works by Padzillah et al. 19 and Piscaglia et al.…”

Section: Introductionmentioning

confidence: 99%

A novel pulse-adaption flow control method for a turbocharger turbine: Elastically restrained guide vane

Wang

Zhang

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part C:

View full text Add to dashboard Cite

A turbocharger is a key enabler for energy conservation in an internal combustion engine. The turbine in a turbocharger is fed by highly pulsating gas flow due to the reciprocating engine, resulting in significant deterioration of the turbocharger performance. To solve this problem, a novel pulse-optimized regulation mechanism named ‘elastically restrained guide vane’ for a novel variable geometry turbocharger is proposed in this paper. The new mechanism regulates the instantaneous flow angle at turbine inlet due to guide vane's self-adaptive rotation under interactions of the elastic force by elastically restrained guide vane and the aerodynamic force from flowing gas, which is different from the traditional variable geometry turbocharger that is achieved by an active control system (e.g. actuator). To investigate the effectiveness of the novel method, a double-passage computational fluid dynamics model is built in ANSYS CFX software combined with a fluid-structure interaction method. The results demonstrate that the pulse-adaptive regulation method can effectively adjust the nozzle opening according to the different pulsating pressures at turbine inlet. Subsequently, based on the calibrated models, the numerical simulation concentrates on the potential gain in turbine eventual power output and the exhaust energy recover as well as the corresponding effects on efficiency as a result of operating the turbocharger in its elastically restrained guide vane mode compared to its operation as a conventional variable geometry turbocharger.

show abstract