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Use of microprocessor-based controllers in place of traditional governor-based controllers for diesel engines is motivated by the requirement of meeting the increasingly stringent legislations on exhaust emissions and fuel economy. Such controllers can also give improved transient performance. In this paper a fourth order nonlinear mean value model of a 600 HP turbocharged diesel engine is developed for the controller design. Differential equations for various subsystems have been derived using first principles, experimental data and characteristic maps. The model is implemented in MATLAB™ and Simulink™ environment for simulation and controller design. The model is generic and can be modified with a little effort for other heavy-duty turbocharged diesel engines. The nonlinear model is linearized at sixteen operating points covering wide operating range. These models are reduced to second and first order models using a balanced realization.

Future emission limits for off-highway application engines need advanced power train solutions to meet stringent emissions legislation, whilst meeting customer requirements and minimizing engineering costs. Development of diesel engines for off-highway application for different power segments need different intake port design solutions to optimise in-cylinder flow structure for efficient combustion. With adaptation of low pressure mechanical fuel injection system, intake port development becomes an important stage for reduction of emission formation at the source and improvement in fuel economy. In this paper, intake port design and development process is elaborated for two different power ratings of 75 hp and 120 hp of off-highway engine. 2-valve and 4-valve configurations are deployed for the same cylinder bore size.

Future emission limits for off-highway application engines need advanced power train solutions to meet stringent emissions legislation, whilst meeting customer requirements and minimizing engineering costs. DI diesel engines with four valves per cylinder are widely used in off- highway applications because of the fundamental advantages of higher volumetric efficiency, lower pumping loss, symmetric fuel spray & distribution in combination with the symmetric air motion which can give nearly optimal mixture formation and combustion process. As a result, the fuel consumption, smoke levels and exhaust emissions can be considerably reduced. In particular, the four-valve technology, coupled with mechanical low pressure and electronic high pressure fuel delivery systems set different requirements for inlet port performance. In the present paper four valve intake port design strategies are analysed for off highway engine using mechanical fuel injection systems.