Butz T.,TESIS DYNAware GmbH |
Simeon B.,TU Munich |
Stadler M.,Bain and Company Switzerland Inc.
Journal of Computational and Nonlinear Dynamics | Year: 2010
The calibration of complex simulation models for vehicle component and controller development usually relies on numerical methods. In this contribution, a two-level optimization scheme for estimating unknown model parameters in a commercial real-time capable vehicle dynamics program is proposed. In order to increase the reliability of the model coefficients estimated from reference data, the measuring test is improved by methods for the optimal design of experiments. Specifically, the control variables of the experimental setup are adjusted in such a way as to maximize the sensitivity of the parameters in demand with respect to the objective function. The numerical results show that this two-level optimization scheme is capable of estimating the parameters of a multibody suspension model. © 2010 by ASME.
Fischer R.,Tesis Dynaware GmbH |
Butz T.,Tesis Dynaware GmbH |
Ehmann M.,Tesis Dynaware GmbH |
Vockenhuber M.,Magna Powertrain AG and Co. KG
AutoTechnology | Year: 2011
The increasing number and complexity of mechatronic control systems in vehicles means that they can no longer be developed and adjusted without the assistance of simulation models and tools. A contribution to this is made by the driver model from Tesis Dynaware, which allows various driver types to be simulated. In the evaluation of traction control systems for all-wheel vehicles from Magna Powertrain, it was possible to successfully meet high demands such as that for control over the vehicle under low friction coefficient conditions. The results for the adjustment of all-wheel systems show good behaviour with regard to subjective evaluation by experienced test drivers and according to objective development criteria.
Kormann M.,TESIS Dynaware GmbH |
Schaber R.,MTU AG
Proceedings of the ASME Turbo Expo | Year: 2014
Flying requires a high power density in the propulsion system. Currently only turbofan engines can provide the required power at a low system mass. To counter a potential negative impact of aircraft emissions on global climate, the agreement Flightpath 50, created by European research establishments and industries, has set the target to reduce overall CO2 emissions from the year 2000 to 2050 by 75 %. In contrast, the air traffic volume has been growing constantly since the 1980s and will be growing further. Hence the fuel burn of aero engines has to be reduced to reach the Flightpath 50 target. High-end component technology has nearly exhausted full potential in the improvement of conventional turbofan engines. Further significant progress can only be achieved by new engine concepts. The geared turbofan has proven the feasibility of this approach. The introduction of a gear allows the IPC and LPT to run at more suitable speeds with the consequence of a lower stage count compared to conventional turbofans. According to Pratt&Whitney this will reduce the fuel burn by "15-16% versus today's best engines" . As a next step towards Flightpath 50 MTU Aero Engines AG envisioned the Intercooled Recuperative Aero Engine (IRA) for long-haul application. This concept increases the thermodynamic efficiency of the core engine by utilizing two heat exchangers: an intercooler reduces the work which is necessary for the compression. A recuperator transfers heat of the exhaust gas to the compressed gas entering the burner. In long-haul aircraft the increased engine mass due to the heat exchangers has a lower influence on the fuel burn. To broaden the research, this paper investigates the application of the IRA for regional jets. An extensive predesign parameter study was performed to find the optimal IRA configuration for regional jets. Not only has fuel consumption been taken into consideration, additionally the influence of the increased weight of the IRA has been included. In optimum, the fuel burn on a regional mission according to this study could be reduced in the order of 1-2%. However, the overall pressure ratio is much lower compared to modern turbofan engines, which leads to relatively low NOx emissions. It allows the introduction of Lean Premixed Prevaporized (LPP) burner technology, promising an additional significant reduction in NOx emissions compared to modern turbofan engines. Compared to a longhaul application the heat exchangers are not a scaled version but the result of a cycle optimization considering the available space. The paper also gives an outlook for an innovative three dimensional heat exchanger. The novel heat exchanger arrangement promises a better integration into the annulus at turbine exit and less aerodynamical pressure losses due to 3D-effects. Copyright © 2014 by ASME.