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A study has been undertaken to demonstrate the use and potential benefits of actively controlled coolant jets in a vehicle. Results have shown that active control of cooling jets has the potential to regulate the temperature of thermally critical areas of the cylinder head, in this case the exhaust valve bridge. In addition the temperature gradient across the head from the exhaust valves to the inlet valves is directly influenced. These capabilities offer improved control of the combustion process and enhanced durability. Furthermore the system allows heat to be rejected at much lower overall coolant flow rates than with a conventional arrangement. The technique relies on an adequate supply of coolant at a lower temperature than that within the engine and on the availability of a suitable measurement technology within the thermally critical region. Unlike passive precision cooling the active jets allow optimization of the cooling at all engine speed / load points.

The Milner CVT is a patented [1] rolling traction transmission offering advantages of high power density and simplicity of construction and operation. A 90 mm diameter prototype variator is described which was sized for a maximum rated input power of 12 kW. Experimental data are presented demonstrating high efficiency and low shift forces. Resistance to overload torque is shown to be exceptional and preliminary durability trials indicate a highly viable concept for series production. Based upon the measured data, characteristics of larger variators are predicted and prospects for automotive applications discussed.

The series sequential turbocharging technology is recently gaining attention as the new round of engine downsizing and emission control becomes imperative for the engine manufacturers. The technology is able to provide combined benefits of transient performance, engine downsizing, fuel efficiency and emissions reduction with foreseeable problems of control, packaging and cost. The matching and characterization of the two interactive turbochargers is a challenging exercise. Two important questions are, how should the two machines be sized and what is the best strategy for the turbochargers across the speed range of the engine at full load. This paper addresses these two questions by comparing a variety of matching sizes and presenting an attempt to identify an optimal valve operating schedule in order to achieve the target limiting torque curve.