Predicting Trends in Engine Performance a) Write an expression for bmep in terms of the thermal...

Predicting Trends in Engine Performance

a) Write an expression for bmep in terms of the thermal efficiency, mechanical efficiency, volumetric efficiency, and combustion efficiency, as well as other engine design parameters. Group terms together that are related to engine thermochemistry, engine fluid mechanics, and engine kinematics/machine design. Identify each of these groupings.

b) Write an expression for the brake specific fuel consumption in terms of the mechanical efficiency, thermal efficiency, and combustion efficiency as well as the heating value of the fuel.

c) Reasoning with your equations, indicate the sign (+, -, or 0) of the likely change in bmep and also in bsfc based on modification of the design or operating parameter. Assume that all other design/operating conditions remain the same. Provide a short rationale for each answer.

- Increasing ambient temperature

- Decreasing ambient pressure

- Increasing engine displacement

- Increasing the air/fuel ratio

- Using a lower viscosity lubricant

- Improving intake/exhaust tuning

Expert Solution

samet mamat answered 1 year ago

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