2. The Process of Combustion in Engines P M V Subbarao Professor Mechanical Engineering Department Creation of Right Environment for Digestion of Diet …...

3. Events in Combustion Processes Pre-processing of fuel an air. The initiation & stabilization of reaction. Execution and completion of the reactions. Post reaction events.

4. Pre-processing of fuel & Air Pre mixing of fuel and airNo Pre mixing of fuel and air Partial Pre mixing of fuel and air

5. Status of Fuel & Air Before Onset of Combustion

6. Care for Occurrence of Combustion Occurrence of combustion in SI Engine : A Child Care Event. Occurrence of combustion in CI Engine: A Teen Care Event. CI Engine SI Engine

7. Type of Fuel Vs Combustion Strategy Highly volatile with High self Ignition Temperature: Spark Ignition. Ignition after thorough mixing of air and fuel. Less Volatile with low self Ignition Temperature: Compression Ignition, Almost simultaneous mixing & Ignition.

8. Types of Digestion of Diet Artificial Perturbation of fuel-air Mixture. –All pre-process should be completed before perturbation. –Digestion succeeds all the preprocess. –Pre-mixed digestion/combustion. Natural Perturbation of fuel-air Mixture. –A degree of pre-processing initiates the perturbation. –However, pre-processes are accelerated during perturbation. –Pre-process continue till the end of digestion. –Simultaneous/Diffusive digestion/combustion.

9. What is the impact of combustion strategy on cycle area? What needs to be studied to judge the suitability of a given strategy???

10. Gross Thermal Energy release in an Engine m number of reactants convert into n number of products, in order to release the required heat in an engine cycle. True available air will influence the number and quantity of products. The fraction of fuel chemical energy available to the cycle from actual combustion is quantified using combustion efficiency. The Gross chemical energy release due to actual combustion with in the engine is: