Wolfgang Reik: LuK

Introduction

The well-accepted effect of CO2 and other emissions on global warming and the expected penalties in Europe for every percent of CO2-emission exceeding a certain level have given a big push towards more efficient drive trains.

Today, technical solutions are being considered which have been refused in the past. The pressure on the car manufacturers to reduce fuel consumption has increased significantly, so even additional cost will be accepted to achieve the goals.

The drive train will presumably have to make the decisive contribution since it is particularly in the engine but also in the transmission that a not inconsiderable portion of the energy held in the fuel is lost. Figure 1 shows the flows of energy. Of 100% of the energy held in the fuel, only approximately 18% actually reaches the wheel. This example was based on a manual transmission. In an automatic transmission, with its higher transmission losses, the proportion reaching the wheel would be even lower.