University Report: Detailed Explanation of Spark Plug Functionality

This report provides a technical description of a spark plug, explaining its function in an internal combustion engine. It details the spark plug's components, including the insulated center electrode, ground terminal, and their role in igniting the air/fuel mixture within the engine cylinder. The report explains the process of how the spark plug receives electrical energy, generates a spark, and ignites the fuel. It further describes the operation, including the connection to the ignition coil, the voltage generation, and the ionization of the gas to allow current flow, highlighting the need for high voltage (over 20,000 volts) for proper firing. The report references several sources to support its explanation and includes figures to illustrate the structure and function of the spark plug.

Running head: HOW SPARK PLUG WORKS
HOW SPARK PLUG WORKS
Name of the Student
Name of the University
Author Note

HOW SPARK PLUG WORKS 1
Spark plug:
A spark plug is one electrical device which can fit within the head of the cylinder of
some of the combustion ignites and engines that are compressed aerosol gasoline by the
meaning of one electric spark (Abdel-Rehim, 2013). The spark plugs are having an insulated
centre electrode that is connected through a wire that is insulated heavily to a magneto and
ignition circuit on the outside, with one ground terminal that is on the base of the plug.
(Figure 1: Structure of Spark plug)
(Source: Laurain, Lauber & Palhares, 2015)

2HOW SPARK PLUG WORKS
How spark plug works:
Actually this is what happens, the spark plugs sit on the top of the cylinder. Firstly,
the piston goes down to the cylinder and draw in the mixture of air as well as fuel. Then the
piston travels back towards to the spark plug (Laurain, Lauber & Palhares, 2015). At the time
the piston is at the fullest reach of it or top dead centre (TDC), the spark plug ignites and
sparks the mixture. A Four-cylinder car must be having four spark plugs, such as a six-
cylinder car will be having 6 spark plugs.
There are two primary specific functions of a spark plug:
The ignition of the mixture of air/fuel is being done by making the spark plug receive
electrical energy. The condition where a high voltage is being passed the gaps in the firing
end of the plug is jumped in between. In the chamber of the combustion the gasoline/air
mixture is being ignited by the spark formed by the electrical energy. No heat is being formed
by the spark plugs, instead, only removal of heat is being done (Fernandes, Lönarz &
Weyand, 2016). A maintenance of temperature in the firing end of the plug has to be
maintained so that temperature should be low enough for the prevention of pre-ignition and
for the prevention of fouling the temperature has to kept high enough. The thermal energy
that is unwanted in the system is being pulled out by the spark plug that acts as a heat
exchanger and the heat that is being pulled out from the chamber is transferred to the system
that is responsible for the cooling of engines. The ability of dissipation of heat from the tip is
what is being defined as the heat range of the spark plug.

3HOW SPARK PLUG WORKS
(Figure 2: A group of four spark plugs which have the same centre electrode but with
different numbers of ground electrodes)
(Source: Abdel-Rehim, 2013)
Operation:
There is a connection between the plug and a high connection, generation of which
takes place by a magneto or coil of ignition. There is a production of difference in voltage
between the electrode at the centre and the electrodes at the side, when there is a flow of
electrons takes place from the coil (Li et al., 2013). The gap that is present between the air
and fuel acts as an insulator and hence the current cannot flow. However, the gas structure is
changed that is present between the electrodes with the further rise in voltage. Ionization of
the gas takes place when the gas’s dielectric strength becomes lower than the voltage
produced. The gap now becomes an insulator due to the ionization of the gas and allows the
flow of the electrons through the gap. For the proper firing of the spark plugs a voltage higher
than 20,000 volts is required.

4HOW SPARK PLUG WORKS
References:
Abdel-Rehim, A. A. (2013). Impact of spark plug number of ground electrodes on engine
stability. Ain Shams Engineering Journal, 4(2), 307-316.
Laurain, T., Lauber, J., & Palhares, R. M. (2015, June). Observer design to control individual
cylinder spark advance for idle speed management of a SI engine. In 2015 IEEE 10th
Conference on Industrial Electronics and Applications (ICIEA)(pp. 262-267). IEEE.
Fernandes, F., Lönarz, M., & Weyand, P. (2016, November). Development of an Ignition
Coil Integrated System to Monitor the Spark Plugs Wear. In International Conference
on Ignition Systems for Gasoline Engines (pp. 140-151). Springer, Cham.
Li, Y. N., Chen, W., Wei, X., & Zhao, F. (2013). Simulation Analysis of Electromagnetic
Compatibility in Vehicle Ignition Control System. In Proceedings of the FISITA 2012
World Automotive Congress (pp. 543-555). Springer, Berlin, Heidelberg.