Developmental methodology for generic compilation of load cases for conceptual design of commercial vehicles

Kurzfassung

The goal of this methodology is to achieve a tool, which generates generic load cases for commercial vehicles. These are required for the future conceptual design of energy and thermal management. Fuel and Gas are continuously getting more expensive for years. To save fuel and costs the vehicles should be optimized. Commercial vehicles are used for many different application purposes. The load cases are just as well varying for different purposes. For example, it is not possible to compare the load conditions between a long distance transport vehicle with a garbage collection truck. The first of them is used in a stationary, the second one in a stop and go purpose. Specific load cases have to indicate those differences and build up a basis for the future design of the thermal and energy management of power train and auxiliary aggregates. First of all one must collect the real load cases, e.g. via GPS, and prepare them by an innovative method. The load cases are analyzed by their different uses. The working and driving load profile have to distinguish. The Engine can be used in a different way. Some of the drive auxiliaries are turning-off and those for stationary work are turning-on. During the second step the particular load case would be evaluated by its statistical frequency distribution. In the next step the chronological sequence of individual load cases would be considered. It will be analyzed for the length of acceleration or braking sequences. Afterwards the base, average and peak load are analyzed, to show the utilization of this vehicle. The load cases will be completed. Several load components are generated off a statistical evaluation under consideration of the weighting of the load cases. The prepared areas from the above mentioned steps also included in the load components results. In turn these components are used to compose the specific reference load profile. That is the basic of the simulations surroundings.