For same compression ratio, the efficiency of an Otto cycle is higher than that of the diesel cycle.
Which cycle is the most efficient of these for the same compression ratio?
Explanation: Otto cycle is more efficient than Diesel cycle for a given compression ratio.
Which cycle is more efficient?
Classical thermodynamics indicates that the most efficient thermodynamic cycle operating between two heat reservoirs is the Carnot engine [1] , and a basic theorem expresses that any reversible cycle working between two constant temperature levels should have the same efficiency as a Carnot cycle [2].
Which cycle has the highest efficiency for the same compression ratio and heat addition?
The cycle which has the least heat rejected will have the highest efficiency. Thus, the Otto cycle is the most efficient and the Diesel cycle is the least efficient of the three cycles.
Which is more efficient out of Otto Diesel and dual cycles for the same compression ratio and heat rejection?
For the same compression ratio and heat rejection, heat supplied is more in Otto cycle and hence it will be more efficient than Diesel and Dual will be in between these two.
Which cycle is idealized cycle for the compression ignition engines?
An air standard diesel cycle is the idealized cycle for the compression ignition engines. Explanation: Diesel cycle consist of one isobaric process, one isochoric process and two adiabatic process.
Which cycle is most efficient cycle for same maximum pressure and heat input?
The maximum pressure is same and same heat input is given. It is clear from T-S diagram that heat rejected by diesel cycle (4′ – 1) is less than heat rejected by Otto cycle (4 – 1). Hence the diesel cycle is more efficient than Otto cycle.
Which cycle is more efficient for electricity generation plant?
The Brayton (gas turbine) cycle , which makes one-half of the electricity in the IFCC, is inherently more efficient than a Rankine (steam) cycle, because there is no loss of the heat of vaporization of the water to make steam in the Brayton cycle.
What is the efficiency of Otto cycle?
(3.15) (3.16) The ideal Otto cycle achieves the Carnot efficiency of an engine working between the maximum, pre-combustion, temperature and the intake temperature. This means that the ideal Otto cycle cannot achieve the Carnot efficiency determined by the highest and lowest temperature during the cycle.
What is the compression ratio for Otto cycle?
In the ideal Otto cycle the fuel-air mixture is introduced during the induction stroke and compressed to a much lower compression ratio ( around 8:1 ) and is then ignited by a spark. The combustion results in a sudden jump in pressure while the volume remains essentially constant.
What would happen when the compression ratio is constant in a diesel cycle?
In this case when the compression ratio is the same, more heat can be added in Otto cycle (at almost constant volume) than that of the Diesel (almost at constant pressure), the heat rejected to atmosphere is the same for both cycles , because of that Otto will have better efficiency than Diesel.
Why is the compression ratio of an Otto cycle limited?
Autoignition – Limit for Compression Ratio
The unburned mixture may autoignite by detonating from pressure and heat alone , rather than ignite from the spark plug at exactly the right time. The engine knocking can be reduced by using high-octane fuel, which increases the gasoline’s resistance to autoignition.
Why CI engines are mostly used?
The compression ignition engine or diesel engine is the type that has most commonly been used for power generation , particularly in off-grid situations. The engine uses a higher compression ratio than a spark ignition engine to heat air in the engine cylinder.
What is diesel cycle and Otto cycle?
In otto cycle heat is added during the constant volume process . So the entire heat added is utilized for increasing the internal energy. Whereas in diesel cycle heat is added during constant pressure process,so while adding heat piston moves downwards so a part of heat added is utilized to obtain work.
What is the difference between the Otto cycle and the diesel cycle?
Otto cycle is used for petrol or spark ignition engine while diesel cycle is used for diesel or compression ignition engine. The main difference between Otto cycle and Diesel cycle is that in Otto cycle heat addition takes place at constant volume and in diesel cycle heat addition takes places at constant pressure.
What is the compression ratio of diesel cycle?
It operates on either a two-stroke or four-stroke cycle (see figure); however, unlike the spark-ignition gasoline engine, the diesel engine induces only air into the combustion chamber on its intake stroke. Diesel engines are typically constructed with compression ratios in the range 14:1 to 22:1 .
