Why don't Formula 1 Cars Use Superchargers

                                    The purpose of supercharging is to raise the volumetric efficiency above that value which can be obtained by normal aspiration. The engine is an air pump. Increasing the air consumption permits greater quantities of fuel to be added, and results in a greater potential output. That indicates power produced is directly proportional to the engine air consumption. While break power is not so closely related to air consumption, it is never the less dependent upon the mass of air consumed.


                                    Supercharging is used to increase the power output for a given weight and bulk of the engine. This is important for aircraft, marine and automotive engine where weight and space are very important. It obtains more power from an existing engine. We can simply say that supercharging increases the power output of the engine with an increase in the amount of air in the cylinder at the beginning of the compression stroke because it allows burning more quantity of fuel.


                                    The main reason behind the supercharging is more preferred in the Compression Ignition engine than the Spark Ignition engine is because supercharging increases the pressure and temperature of the charge at the end of compression. Thus by supercharging, the effective compression ratio is increased. This reduces ignition delay in the C.I. engine, thereby the combustion becomes smooth. The rate of pressure rise in second stage combustion is reduced and the tendency of knocking is avoided. But in the case of S.I. engine, short ignition delay promotes detonation. To overcome this either the compression ratio is reduced or the fuel of higher octane number is used, due to which it increases the operating cost.


Effect of Supercharging on the Engine:-


  • Supercharging increases the power output of the engine. It does not increase the fuel consumption, per brake kwh. The increased pressure and temperature as a result of supercharging may lead to detonation, therefore the fuel used must have better anti-knock properties.
  • A certain percentage of power is consumed in compressing the air. This power has to be taken from the engines itself. This will lead to some power loss. However, it is seen that net power output will be more than that of an engine of the same capacity.
Some Limitation of Supercharging For S.I. and C.I. Engine:-

  • In S.I. engine, It has been observed that for volatile petroleum fuels of high octane number the knocking and pre-ignition tendency is reduced at a very rich and very lean mixture and that the fuels of the same octane value have a different response to supercharging. In the case of alcoholic fuels, the knocks are reduced at a rich mixture. A very lean and very rich mixture gives non-knocking operations. The strongest knocking, however, occurs near chemically correct mixtures. The use of rich mixture results in higher specific fuel consumption for a supercharged engine though knocking is controlled. A slight reduction in the mixture makes the engine operation irregular and intermittent.

  • In the case of the C.I. engine, where the limits of supercharging are due to combustion. The very high temperature of the piston and cylinder causes scuffing of piston rings and heavy liner wear. It has been observed that the load on the bearing is increased due to increased pressure in the cylinder. In the C.I. engine, the reliability of the engine decreases with the increases in maximum pressure in the cylinder. This also increases the thermal load on the engine due to the increases in the rate of heat release.

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