Si engine is internal combustion engine that operates on the principle of spark ignition. It uses petrol and utilizes the Otto cycle. The diesel (Ci) engine is also an internal combustion engine, which uses diesel fuel and operates on diesel cycle.
What is the difference between SI & CI 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.
Which is more efficient SI or CI engine?
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.
What is SI & CI engine respectively?
Abstract. Natural gas is a fossil fuel that has been used and investigated extensively for use in spark-ignition (SI) and compression-ignition (CI) engines. … However, EGR rates above a maximum value result in misfire and erratic engine operation.
What type of fuel is used for SI engine?
In recent times, ethanol has been commonly used as a fuel additive or an alternative fuel in spark ignition (SI) engines and compression-ignition (diesel) engines. The use of ethanol, particularly in SI engines, has become attractive due to its relatively high octane number and the fact that it burns clean [4,5].
Why spark plug is not used in CI engines?
Spark plugs are used in the petrol engines to ignite the air fuel mixture whereas in diesel engines the presence of spark plugs is not necessary. … Normally the compression ratio of SI engines will in the range 6 – 8 . This proves that in petrol engines the compression alone doesn’t makes the fuel to burn.
What is CI engine for?
Compression ignition (CI) engines
In a compression ignition engine only air or air plus residual combustion gases from the exhaust known as exhaust gas recirculation (EGR) is inducted into the chamber during the intake stroke, and compressed during the compression stroke.
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.
How many types of SI engines are there?
There are two kinds of internal combustion engines currently in production: the spark ignition gasoline engine and the compression ignition diesel engine. Most of these are four-stroke cycle engines, meaning four piston strokes are needed to complete a cycle.
Which engine is more powerful?
In very simple terms, higher horsepower translates to a higher top speed and a faster car. Conversely, a higher torque figure translates to more power at a lower RPM. When this is taken into consideration, diesel engines are the more powerful of the two.
Is fuel pump used in CI engine?
Early CI engines used air pressure to deliver the fuel into the cylinder, but nowadays liquid fuel, supplied by a reciprocating plunger pump, is delivered through small bore steel pipelines to the injector, which breaks up the fuel to the required degree and deliver it to combustion region in the chamber.
Which is not use in CI engine?
Why methanol is not used in CI engine? Explanation: Methanol is not used in CI engines because of its high octane number and low cetane number.
Which of the following is the best fuel for SI engine?
engines fuel? Explanation: For C.I. engines fuel most preferred are paraffins and for S.I. engines fuel most preferred are aromatics.