Turbochargers

The technology of these units is very mature, and they are available in a range of sizes, but only for the larger fuel cells, 50 kW or more. They are used on the majority of modem diesel engines and so are mass-produced. Compared to many other parts of a fuel cell system, they are readily available at low cost. 

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Radial-Inflow Turbine The radial-inflow turbine, or inward-flow radial turbine, has been in use for many years. Basically a centrifugal compressor with reversed-flow and opposite rotation, the inward-flow radial turbine is used for smaller loads and over a smaller operational range than the axial turbine. Radial-inflow turbines are only now beginning to be used because little was know about them heretofore. Axial turbines have enjoyed tremendous interest due to their low frontal area, making them suited to the aircraft industiy. However, the axial machine is much longer than the radial machine, making it unsuited for certain vehicular and helicopter applications. Radial turbines are used in turbochargers and in some types of expanders. 

Copper-lead 70% Cu - 30% Pb Crankshaft and camshaft bearings of i.c. engines turbocharger bearings... 

Benisek, E., 1998. Experimental and Analytical Investigation for the Flow Field of a Turbocharger Turbine, IMechE, Paper No. 0554/027/98. 

Common air inlet manifold conducts air from turbochargers to each power cylinder. 

Turbochargers use the expansion of exhaust gas to pump combustion air to an engine. Exhaust gas is directed through a set of nozzles to drive a turbine wheel. Directly connected to the exhaust turbine is an air compressor turbine that delivers combustion air to the power cylinders. Thus, back-pressure is put on the engine exhaust, reducing power slightly, but the net effect of the increase in air mass flow available for combustion i.s to increase horsepower. 

Although turbocharging an engine increases the bhp for a nominal additional capital cost, it has the disadvantage of increasing maintenance costs and decreasing engine reliability. 

Two-stroke cycle machines must be equipped with a scavenge air system that may include a separate scavenge air cylinder, gear-driven blower, or turbochargers. It should be noted, however, that a method must be provided to supply a turbocharged two-stroke cycle engine with air to start. 

Pressure-volume curve illustration for a turbocharged and direct-injected high-speed heavy-duty four-stroke diesel cycle engine. 

In Figure 2 you can see that from position 1 to 2 the piston moves down the cylinder on the intake stroke as it is filled with turbocharger boost air higher than atmospheric pressure, as indicated in line PI. Depending on the valve timing, actual inlet valve closure will control the degree of trapped cylinder air... 

S.M. Vauclain Compound low- and high-pressure 1937 American Locomotive First diesel engine turbocharger... 

CE Service typical of certain turbocharged or supercharged heavy-duty diesel engines operating under both low speed-high load and high speed-low load conditions. Oils designed for this service must also meet the requirements specified for CC and CD classifications. 

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