Heat Losses from the Turbine of a Turbocharged SI-Engine - Measurements and Simulation

Optimisation-oriented modelling of the NOx emissions of a Diesel engine

“…Still, it is able to capture the important effects. The main assumptions are also in line with more dedicated investigations such as [36][37][38][39]. …”

Numerical Simulation Techniques for the Prediction of Fluid-Dynamics, Combustion and Performance in IC Engines Fuelled by CNG

“…Both the compressor speed and pressure ratio usually fit well the measured values (Westin & Ångström, 2003). Conversely, the power from the turbine often has to be adjusted for each single operating conditions for many reasons (Westin et al, 2004): -The flow entering the turbine in the engine installation is heavily pulsating, whereas the turbine performance maps are usually measured under steady-state conditions; -During each engine cycle, the pulsating flow covers a large operating range, and this means that a large portion of the map is covered for each cycle. Often, the map is not measured with a large enough range, thus the software needs to extrapolate it, and this extrapolation may be a source of error; -In most cases, the maps are not measured for the low-speed range of the turbocharger.…”

“…The potential need to adjust the mass-flow or the efficiency multipliers has long been known (Baratta et al, 2010;Gamma Technologies, 2009;Westin & Ångström, 2003;Westin et al, 2004). As far as the compressor is concerned, differences in installation may influence the compressor surge-line shape, as surge depends on the compressor inlet and delivery arrangements (Baines, 2005).…”

“…Finally, it is worth stressing that heat losses from the turbine are usually neglected in the simulations. (Westin et al, 2004) proposed an approach, based on experimental heat-transfer measurements, to account for the heat transferred from the turbine to the surroundings. In this way, the magnitude of the correction needed for the turbine efficiency decreased.…”

“…In GT-Power, the performance tables are pre-processed so as to create internal maps that define the www.intechopen.com performance of the turbine and compressor over a wide range of operating conditions. The topic of turbine table pre-processing is described hereafter, as it is generally accepted that turbine data quality is the most critical point in turbocharged engine simulation (Baratta et al, 2010;Westin & Ångström, 2003;Westin et al, 2004;Winkler & Ångström, 2007). Turbine data pre-processing uses the well-known characteristics of turbines regarding efficiency, reduced mass flow rates and blade speed ratio (BSR).…”