A four-stroke engine is running on methane with an equivalence ratio of 0.8. The air and...

A four-stroke engine is running on methane with an equivalence ratio of 0.8. The air and fuel enter the engine at 250 C, the exhaust is at 5270 C, the heat rejected to the coolant is 340 MJ/kmol of fuel.(a)Write the equations for stoichiometric and actual combustion.(b)By calculating the enthalpy of the exhaust flow, deduce the specific work output of the engine, and thus the overall efficiency. (c)If the engine has a swept volume of 5 Litres, and volumetric efficiency of 72%, calculate the power output at engine speed of 1500 rpm. The ambient pressure is 1 bar.State clearly any assumption that you make, and comment on any problem that would occur with a rich mixture.

Expert Solution

Rich mixture means deficiency of air for complete combustion of fuel, as a result of this product will be having CO. Which will also cause pollution problem in atmosphere.

samet mamat answered 1 year ago

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how do you relate the air fuel ratio to the equivalence ratio, and the ‘lambda’ ratio

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