50 % brake thermal efficiency – the realization of a vision

The Future Heavy-duty Engine - Basic Engine Concept for Maximum CO2 Reduction

“…Considering higher quality of crank shaft and crankcase materials, the following basic parameters are set for the PFP requirements in new engine developments: a cylinder distance to bore ratio of 1.25, taking into account the limit values of the reference stresses of the crankshaft, and a stroke/bore ratio of 1.33, as a good compromise be tween installation space and ther modynamic boundary conditions [2]. As a result of the smaller bore area, the ig nition force is reduced and in addition, a compact piston bowl with a high compression ratio can be real ized for a stable combustion.…”

“…Optimized bore to stroke ratio: In view of thermodynamics, a longstroke engine concept is advantageous due to a more compact combustion chamber surface in the firing top dead center [2]. The reduced wall heat losses even over compensate the disadvantages of higher friction due to higher piston speed and the smaller valves.…”

“…Three basic concepts for turbocharg ing and EGR have been defined and the main features are briefly explained in the following. A detailed description of these concepts including further thermo dynamic aspects and the requirements for future exhaust gas aftertreatment systems are published in various papers [2][3][4][5][6]. The main components of the indi vidual concepts and their expected mod el year 2024 availability are shown in FIGURE 1.…”