New Physics-Based Turbocharger Data-Maps Extrapolation Algorithms: Validation on a Spark-Ignited Engine

Abstract

Objectives in terms of pollutant emissions and fuel consumption reduction, as well as development costs and time to market reduction, has led car manufacturers to use more and more system simulation. However, among all the fields in which it has enabled to achieve these goals, the control development stage is one of those, in which major improvements can still be achieved. In this context and with the increasing penetration of downsized engines, turbocharger modeling has become one of the biggest challenges in engine simulation. This paper focuses on the validation of compressor and turbine data maps, extrapolated using new physics-based extrapolation algorithms. The study led to excellent prediction performances for two classical control-oriented models. Conclusions stresses: 1-The improvement of the extrapolation robustness, in particular in the low turbocharger rotational speeds zone. 2-The possibility to keep a low calculation time as well as maintaining the same calibration effort.

Explicit-Ready Nonlinear Model Predictive Control for Turbocharged Spark-Ignited Engines

“…The steady-state validation detailed in (El Hadef et al, 2012a) shows that the model prediction is very accurate over the entire engine operating range. The error remains well below 10% for most of the operating points.…”

“…In order to bring the offline computation effort under control, a 0D modeling approach combined with a mean value cylinder model was chosen (Moulin et al, 2008). The model is succinctly described below but more details can be found in El Hadef et al, 2012a, Eriksson, 2007, Eriksson et al, 2002, Heywood, 1988.…”

“…The turbocharger model relies on four static data-maps, extrapolated from manufacturers' data. The physics-based method that has been used is presented and validated in (El Hadef et al, 2012a, El Hadef et al, 2012b.…”

The Sensitivity of Transient Response Prediction of a Turbocharged Diesel Engine to Turbine Map Extrapolation

“…Watson and Janota [9] and Benson [10] used a constant eff for all conditions, whilst Payri et al [11] allowed for changes in eff with red and PR, deriving a relation in which eff varies exponentially with BSR. Intermediate approaches have been proposed by El Hadef [5,12] and Martin [8], and [13]. In the former cases, a purely numerical model is developed for eff , whose coefficients are fitted polynomial functions with the PR.…”

“…These are entered into Equation (12), to update the efficiencies. This cycle is repeated until acceptable convergence is achieved.…”