#### Date of Award

Summer 1986

#### Document Type

Dissertation - Restricted

#### Degree Name

Doctor of Philosophy (PhD)

#### Department

Electrical and Computer Engineering

#### First Advisor

Wu, Sherman H.

#### Second Advisor

Elkouh, A. F.

#### Third Advisor

Schutten H. P.

#### Abstract

In a hypergolic internal combustion engine, with a given amount of fuel per power stroke, we wish to optimize the output work and the efficiency by controlling fuel injection . We assume the engine is ideal except for friction losses which are given as a function of the cylinder pressure. This optimization is determined through calculations of thermodynamic efficiency. Cylinder pressure versus crank angle and friction loss characteristics. A mathematical model developed and since the efficiency consists of output work over input fuel constraint. Calculus of variations approach will be used for solving the problem. The constraint is not constant but variable. A new approach shows among the value of constraint. That the maximum efficiency can be optimized. Its inverse problem, in which the output work is constraint also can be optimized. The results of optimizing the problem. shows that the fuel injection starting angle is approximately 5 after top dead center regardless of the amount of fuel injection per cycle. While the ending angle varies from approximately, 7 to 18 with increasing fuel injection per cycle. In a hpergolic combustion engine, since the fuel is activated, the delayed combustion is not expected. It is easy to show that the Otto cycle is optimal, only when a friction less engine is available but this is not practical. The result s show that the Hoppie cycle is about 10% better in comparison to the Otto cycle with friction.