How is the heat added in the Otto cycle?
Through the combustion of fuel, heat is added in a constant volume (isochoric process) process, followed by an adiabatic expansion process power (C) stroke. The cycle is closed by the exhaust (D) stroke, characterized by isochoric cooling and isobaric compression processes.
In which of the following cycle heat is added at constant volume?
IC Engine Questions and Answers – Dual Cycle Explanation: Another name for Dual cycle is a mixed cycle. Explanation: Since, Dual Cycle is a combination of Otto cycle and Diesel cycle, so in Dual cycle, generally heat addition takes place first at constant volume then at constant pressure.
Why is there constant volume heat in Otto cycle?
Otto cycle vs. Diesel cycle in your basiic thermodynamics course. You get work out of the heat added by expanding it (dW=pdV). When you add heat at constant volume, the pressure is allowed to rise, and all of the energy added can be expanded through the whole compression (you may call it expansion) ratio.
How does the performance of an ideal Otto cycle change with the compression ratio of the engine and the specific heat ratio of the working fluid?
How does the thermal efficiency of an ideal Otto cycle change with the compression ratio of the engine and the specific heat ratio of the working fluid? It increases with both of them. The fuel is injected into the cylinder in both engines, but it is ignited with a spark plug in gasoline engines.
How do you calculate the efficiency of a diesel cycle?
The input and output energies and the efficiency can be calculated from the temperatures and specific heats: It is convenient to express this efficiency in terms of the compression ratio rC = V1/V2 and the expansion ratio rE = V1/V3. The efficiency can be expressed in terms of the specific heats and temperatures.
What is the efficiency of dual cycle?
For isentropic process (4-5) It can be noted from Equation A that a value of pressure ratio α > 1 results in an increased efficiency for given value of r and ρ. Hence the efficiency of the dual cycle lies between the Otto and Diesel cycles for given value of compression ratio.
Does constant pressure mean constant volume?
Since the pressure is constant, the force exerted is constant and the work done is given as PΔV. An isobaric expansion of a gas requires heat transfer to keep the pressure constant. An isochoric process is one in which the volume is held constant, meaning that the work done by the system will be zero.
What is the range of thermal efficiency in Brayton cycle?
What is the range of Thermal efficiency in the Brayton cycle? Explanation: Efficiency of Brayton cycle in actual working condition is found to be between 35 to 45%.
Is the Brayton cycle open or closed?
It is also sometimes known as the Joule cycle. The reversed Joule cycle uses an external heat source and incorporates the use of a regenerator. One type of Brayton cycle is open to the atmosphere and uses an internal combustion chamber; and another type is closed and uses a heat exchanger.