Development of IC Engines

·         In a Otto cycle engine, combustion occurs at

Answer: Combustion process in a Otto cycle engine occurs at constant volume.

·         In a Diesel cycle engine, combustion occurs at

Answer: Combustion in a Diesel cycle engine occurs at constant pressure.

·         Heat rejection in diesel cycle is at

Answer: Heat rejection in diesel cycle occurs at constant volume.

·         In a four stroke ic engine the number of strokes covered for one complete crankshaft revolution is

Answer: For a 4 stroke engine, piston covers 2 strokes for one complete crankshaft revolution.

·         Which stroke for a 4-stroke ic engine is considered as the working or power stroke

Answer: Expansion stroke is the working stroke.

·         The valves of an ic engine are made to open and close slowly to

Answer: The valves are made to open and close slowly to provide silent operation under high speed conditions.

·         Which of these is not an assumption made in deriving the formula for air standard of Otto cycle

Answer: Compression and expansion are assumed strictly adiabatic in a Otto cycle.

·         Higher efficiency in Otto cycle can be achieved by

Answer: Higher efficiency can be achieved by increasing the compression ratio.

·         The expansion process in diesel engine is

Answer: Adiabatic expansion occurs in diesel cycle.

·         In two-stroke cycle engines, what replaces valves of a four-stroke engine

Answer: Valves are replaced by ports in two-stroke cycle engines.