Development and Experimental Validation of a Low Order Turbine Model Under Highly Pulsating Flow

This article presents the experimental validation of a quasi-two-dimensional radial turbine model able to be used in turbocharged reciprocating internal combustion engine simulations. A passenger car variable-geometry turbine has been tested under steady and pulsating flow conditions, instrumented with multiple pressure probes, temperature sensors and mass flow sensors. Using the data obtained, a pressure decomposition has been performed. The pressure at the turbine inlet and outlet has been split into forward and backward travelling waves, employing the reflected and transmitted waves to verify the goodness of the model. The experimental results have been used to compare the quasi-two-dimensional radial turbine model as well as a classic one-dimensional model. The quasi-two-dimensional code presents a good degree of correlation with the experimental results, providing better results than the one-dimensional approach, especially when studying the high-frequency spectrum.

Section: Introductionmentioning

confidence: 99%

Experimental validation of a quasi-two-dimensional radial turbine model

Galindo

Arnau

García-Cuevas

et al. 2018

“…With this purpose, Winterbone et al 5 and Winterbone and Pearson 6 performed a rigorous review on the topic. Investigators have also performed different experiments for pulsating flow in single-entry turbines, such as Torregrosa et al 7 or Serrano et al 8 for unsteady and off-design performance, Torregrosa et al 9 for diesel engines or Hohenberg et al 10 Piscaglia et al 11 show an interesting approach measuring the instantaneous pressure, temperature and mass flow in different points in the turbine inlet duct and the turbine outlet duct. Galindo et al 12 present a similar experimental methodology as the one presented in this article, being applied for a variable geometry turbine (VGT).…”

Section: Introductionmentioning

confidence: 99%

Experimental validation of a one-dimensional twin-entry radial turbine model under non-linear pulse conditions

Serrano

Arnau

Soler

et al. 2019

This article presents the experimental validation of a complete integrated one-dimensional twin-scroll turbine model able to be used in reciprocating internal combustion engine unsteady simulations. A passenger car with a twin-entry-type turbine has been tested under engine-like pulse conditions by means of a specifically built gas stand. To obtain high-resolution quality data, the turbine and turbine line pipes have been instrumented with mean and instantaneous pressure sensors as well as temperature and mass flow sensors, employing a uniquely designed rotating valve for the pulse generation. This experimental configuration enables to obtain the pressure decomposition in both inlets and outlets of the turbine. Using the experimental data obtained, the model is fully validated, with special focus on the reflected and transmitted components for analysing the performance of the model and its non-linear acoustics prediction capabilities. The model presents a very high degree of correlation with the experimental results, providing a range of errors similar to the uncertainty of the measurements, even in the medium- and high-frequency spectra.

“…The models for predicting the performance of radial turbines, including their behaviour in pulsating flow conditions, have evolved during the last decades as the computational resources have improved. From the early models proposed by Wallace and Adgey 14 or Winterbone and Pearson 15 to the newest additions proposed by Hohenberg et al, 16 Ding et al 17 or Piscaglia et al, 18 they tend to focus on performance parameters such as the instantaneous flow rate or torque. Even high-fidelity three-dimensional simulations are routinely carried out in the present day, as in the work by Galindo et al, 19 where a radial turbine is simulated under pulsating flow conditions.…”

Section: Introductionmentioning

confidence: 99%

Radial turbine sound and noise characterisation with acoustic transfer matrices by means of fast one-dimensional models

Torregrosa

García-Cuevas

Inhestern

et al. 2019

Estimating correctly the turbine acoustics can be valuable during the engine design stage; in fact, it can lead to a more optimised design of the silencer and aftertreatment, as well as to better prediction of the scavenging effects. However, obtaining the sound and noise emissions of radial turbocharger turbines with low computational costs can be challenging. To consider these effects in a time-efficient manner, the acoustic response of single-entry radial turbines can be characterised by means of acoustic transfer matrices that change with the operating conditions. Exploiting the different time-scales of the acoustic phenomena and the change in the operating point of the turbine, lookup tables of acoustic transfer matrices can be computed. Then, the obtained characterisation can be used in mean-value engine models. This article presents a method for generating these lookup tables by means of fast one-dimensional simulations of thoroughly validated fidelity, in terms of both acoustics and extrapolation capabilities. Due to the inherent behaviour of radial turbines, the number of computations needed to fill the lookup tables is relatively small, so the method can be used as a simple preprocessing phase before mean-value simulation campaigns.