Computational Investigations of Large-Bore DI Diesel Engines
Waertsilae SwitzerlandLtd. designs and develops medium to
slow-turning diesel engines for marine and stationary applictions with
a power output of upto 66000 kW. The challenges in the further development
of these engines include the arrangement of the injection configuartion
such that the thermal stress of the piston, the valves and the cylinder
walls are minimized, while maintaining optimal engine efficiency and minimal
pollutant formation.
Project: Injection of Fuel/Water Mixtures into the Combustion Chamber
The injection of water into the combustion chamber is an efficient method
to reduce the nitric oxyde formation in a diesel engine. This can be achieved
through the injection of a fuel/water emulsion or of alternating fuel/water
packages through the existing fuel injection nozzles, or alternatively,
through the injection of water by means of separate water injection nozzles.
The objective is the distribution of the water in such a way, that an efficient
cooling of the hottest heat pockets in the combustion chamber are achieved,
which results in the reduction of the thermal nitrix oxyde formation.
Project: Investigation of the Injection Nozzle Configuration
Number, location and direction of the nozzle orifices belong to the important
parameters which optimize the operating conditions of an engine. In the
past, these parameters have been determined by means of extensive experimental
test series. Computational tools are a promising way to avoid such lengthy
and expensive eperimental procedures. The objective of this project is
the evaluation of the presently available simulation tools for the design
process of injection systems. In addition, the computational investigations
are expected to help in the interpretation and explanation of experimentally
observed trends, and will serve as an important basis to derive optimal
injection configurations.
Project: Performance of a Common-Rail Injection System
The common-rail injection system for heavy oil, developed recently by Waertsilae
NSD, offers enormous possibilities for the optimization of the the inner-cylinder
processes. The computational investigations performed in the framework
of this project serve the interpretation of experimentally observed behavior
and appropriate parameter variations are expected to lead to further optimization
of the combustion process.
Industry Contact: German Weisser, Waertsilae NSD Switzerland, CH-8401 Winterthur,
Switzerland german.weisser@wartsila-nsd.com,
Tel: +41 (0)52 262 443