What is CI engine and SI engine?
in S.I engines,ignition process is carried out with the help of a spark plug which ignites a mixture of air and fuel that is compressed in the combustion chamber. Whereas,a diesel engine also known as Compression Ignition (C.I) engine works on the basis of Diesel cycle or Constant pressure heat addition cycle.
What is CI and IC engine?
Normally, it is a petrol engine. In this type of engines, spark generated by spark plug is responsible for combustion of air-fuel mixture. But in Compression Ignition engines (CI engines) combustion process starts by the heat generated from compression together with the injection of fuel starts.
What are the physical difference between SI and CI engines?
Now Let’s See the Difference Between SI and CI Engine:
|SI Engine||CI Engine|
|The compression ratio is 6 to 10. The upper limit is fixed by the antiknock quality of the fuel.||The compression ratio is 16 to 20. The upper limit is limited by the weight increase of the engine.|
Which is better Si or CI?
CI Engine (Compression Ignition Engine)
It has high compression ratio because of the high ignition temperature of the diesel fuel. The heat of the compressed air ignites the fuel. Due to the high compression ratio it produces more power. … The maintenance cost of the CI engine is more as compared with the SI engines.
How does CI engine works?
The compression ignition engine operating on liquid fuels, or in the dual-fuel mode, works on the principle of fuel being injected into a charge of compressed air and spontaneously ignited by the high temperature of the induced air by the heat of compression.
Which is not use in CI engine?
Explanation: Methanol is not used in CI engines because of its high octane number and low cetane number. Pure methanol and gasoline in various percentages have been extensively tested in engines and vehicles for a number of years.
Why spark plug is not used in CI?
Why Diesel Engines Don’t Need Spark Plugs. A gas engine requires spark plugs to create a spark to ignite the gasoline and create the combustion stroke of the piston. … A spark plug has no use with diesel fuel because there is no need to ‘light’ the diesel fuel. Instead, the glow plug only heats the combustion chamber.”
Is IC and CI engines same?
CI engine is a type of IC engine. Another type of IC engine is SI engine which stands for Spark Ignition. (In which ignition takes place by using a spark plug). A CIE is a specific type of ICE – Specifically Diesel Engines are CIE’s Compression Ignition Engines.
Why SI engines are high speed engines?
SI Engines operates at higher speed due to their less compression ratio (i.e. less weight per unit power). They produce less torque and operates at higher speed.
What is the classification of SI and CI?
The most prominent difference between Spark Ignition (SI) and Compression Ignition (CI) engines is the type of fuel used in each. In SI engines petrol or gasoline is used as fuel, hence these engines are also called petrol engines. In CI engines diesel is used as fuel, hence they are also called diesel engines.
What is the range of air fuel ratio for SI and CI engines?
For most of the hydrocarbon fuels, the stoichiometric air-fuel ratio is 15 : 1. SI engine operates around this ratio during normal operation. The air-fuel ratio for CI engines varies from 18 : 1 to 80 : 1 from full load to no load.
Which is more efficient SI or CI engine explain with technical reasons?
CI engines have higher Thermodynamic Efficiency
With a higher compression ratio in CI engines as compared to SI engines, CI engines have a higher thermodynamic efficiency since more work is done with each expansion stroke.