Difference Between Flywheel and Governor (With Table)

Flywheel and Governor are mechanical devices that are used to regulate and control the fluctuations in speed. They both work to stabilize the speed of the vehicle. There is not much difference in the purpose they serve for the vehicle, so the only differences we can find are in the working mechanism of these devices.

The difference between Flywheel and Governor is that the operation of Flywheel is continuous and it is always under operation whereas the operation of governor is limited to only when the engine is not running at its mean speed.

There is also a difference between their working. The regulation of the variations in speed at the crankshaft is done by the flywheel while the variation of speed caused by the variation of load is controlled by the governor. Also, the flywheel is way more heavier than the governor.

The flywheel is responsible for storing the rotational energy in case where the mechanical energy provided is more than the required amount. On the other hand, the governor is responsible for regulating the fuel supplies to the engine according to the variations in load conditions.

Comparison Table Between Flywheel and Governor

Parameters of ComparisonFlywheelGovernor
DefinitionFlywheel is a heavy rotating wheel which decreases the jerk due to certain fluctuations in the speed.Governor is a speed controller device that regulates and controls the variations in speed due to the variations in loads.
Operating timeFlywheel operates continuously and for all the time the engine runs.Governor operates only when the engine is not running at its mean speed.
Working mechanismThe working of flywheel includes limiting the variations in speed due to the difference between active torque and driving torque during each and every thermodynamic cycle.The working of governor includes making sure that the engine is running at its mean speed within the specified limits under conditions where the load is varying by adjusting the supply of fuel to the engine during the entire cycle.
FunctionThe flywheel device stores the rotational energy when there is an excess of mechanical energy to avoid fluctuations in energy.The governor device helps in maintaining the mean speed of the engine constantly over a period of time by regulating the amount of fuel flowed.
UsageThe usage of a flywheel in all engines is not compulsory.It is compulsory to use the governor in all engines.
WeightFlywheel is comparatively heavier than the governor and has a large amount of inertia.Governor is lighter than the flywheel and also has a small amount of inertia.

What is Flywheel?

A rotating wheel which is heavy and is attached to a revolving shaft is called a Flywheel. It helps in smoothing out the delivery of power of the reciprocating engine. This power is generated due to difference in the active torque and the driving torque over each thermodynamic cycle. 

In easier words, it’s a device that stores any excess of rotational energy in the system and then uses it for any intermittent use. Due to the continuous flow of energy, if there is a discontinuity in the energy source, it can be avoided. When the flywheel is connected to an automatic transmission, it is called a flex plate.

What is Governor?

A mechanical device which has the ability to control the mean speed of an engine when there is a varying load is called a governor. It is a compulsory device used in all engines which measures and regulates the speed of the engine even if there are variations in the load.

Also, it maintains the speed of the vehicle within specific limits. When the load varies, the governor controls the fuel supply and changes the configuration likewise. It cannot store or provide energy like the flywheel.

Main differences Between Flywheel and Governor

  1. Flywheel is a heavy rotating wheel which reduces the jerk due to certain variations in the speed of the vehicle whereas Governor is a device which controls the variations in speed due to the varying loads.
  2. The working mechanism of flywheel consists of limiting the fluctuations in speed due to the difference between active torque and driving torque during each thermodynamic cycle while the working mechanism of governor consists of making sure that the engine is running at its mean speed within the specified limits under conditions when there is a varying load by adjusting the fuel supply to the engine.
  3. The operation of Flywheel is continuous and it is always under operation whereas the operation of governor is only when the engine is not running at its mean speed.
  4. Flywheel is not compulsory to be used in every engine while the governor is a compulsory device for all engines.
  5. Flywheel is heavier than the governor and also has more amount of internia in comparison to the governor.

Conclusion

The purpose of both flywheel and governor is the same which is to regulate the speed of the engine but the way they do so is different. Flywheel is a heavy rotating wheel which reduces the jerk due to the variations in the speed. Governor is a device which controls the fluctuations in speed due to the varying loads

The purpose of flywheel is to store the rotational energy when there is an excess of mechanical energy to prevent any variations in energy while the purpose of the governor device is to maintain the mean speed of the engine constantly by regulating the amount of fuel flowed to the engine.

Also, flywheel period of operation is continuous and all the time while on the other hand the period of operation of governor is limited and only when the engine is not running at it’s mean speed. The governor is a light weighing device and has a small amount of inertia. The flywheel is a heavy weight device and has a large amount of inertia.

Refrences

  1. https://www.sciencedirect.com/science/article/pii/S1007570417300941
  2. https://iopscience.iop.org/article/10.1088/1674-1056/21/3/030502/meta