This high-speed automotive diesel engine was designed to achieve the greatest possible reliability in operation, low operating and maintenance costs and maximum versatility of component and auxiliary arrangements, based on long experience of large-scale manufacture of engines for commercial vehicles and the increases in power output and time between overhauls made possible by improvements in design, materials, manufacturing processes, fuels and lubricants. Elimination of the cylinder high-pressure joint was a radical departure from current practice and promised considerable advantages in cooling, reducing thermal stress and freeing restrictions in cylinder-head porting layout. Thus the potential for operating at the highest rating now in use and for future development was improved. This paper deals with the design aims, describes the engine and outlines the development work with single and multi-cylinder engines that has been undertaken to ensure that each commercial variant meets the requirements of its rating. Vertical and horizontal configurations are used in naturally aspirated and pressure-charged versions. For automotive work, using mechanical transmissions, the drooping characteristic of the normal turbocharged engines torque curve at low speed is a serious disadvantage. Measures taken to overcome this are described. These included variations in camshaft timing, automatic variable control of injection timing and boost pressure control of fuel injection quantity to avoid undesirable smoke in the exhaust emission in addition to the normal development work of ensuring the highest practicable standards of mechanical, volumetric and combustion efficiency. Other methods such as special turbocharger matchings, including the waste-gate system of turbine by-pass, the system of auxiliary hydraulic drive of the turbocharger at low engine speeds and, as alternative to turbocharging, pressure charging by an aerodynamic pulse-converter are discussed. At the other end of the scale, considerable attention has been paid to increasing the maximum engine output by turbocharging with intercooling which promises to increase naturally aspirated power by over 100 per cent, if in road vehicles the problem of the intercooler, air/air or air/water, can be dealt with satisfactorily.
Adaptive Boost Pressure Control for Four-Stroke Diesel Engine Marine Application in the Presence of Dynamic Uncertainties
