Types of Heat Engines Currently in Use

Heat engines are an important topic in engineering and thermodynamics. A heat engine can be described as an arrangement of converting heat into another form of energy, i.e., mechanical energy to do useful work like repair, transportation, electricity, etc. Engines work by burning different fuels like coal, natural gas, petro, diesel, etc., to release heat; for this reason, they are called heat engines. Heat engines accomplish the mechanical work by transferring a working matter from a higher temperature to a lower temperature state. Diesel engines, gasoline engines, and steam turbines are some examples of heat engines. 

What is a Heat Engine?

A heat engine is a mechanism used to extract heat from fuel and convert it into energy to do mechanical work. For example, a steam engine on a train can produce the heat for the work required for driving the train. Heat engines include petrol and diesel engines, steam turbines, and jet engines that generate electricity. Engines can be categorised into two parts, i.e., combustion and non-combustion. A heat engine is an example of a combustion engine, where fuel is burned in oxygen in the air to make carbon dioxide and steam. The process of fuel combustion generates chemical energy, which is transferred as heat all through the gas in a fuel tank.

Types of Heat Engines

There are two types of heat engines 1. Internal Combustion Engines and 2. External Combustion Engines. Let’s learn about these two in detail:

Internal Combustion Engines 

ICE or Internal Combustion Engines involves the method of burning the fuel within the working body. These heat engines are the most common and are currently in use as they are being used in different vehicles like a train, aeroplanes, boats, ships, and cars. These engines are named ICE or Internal Combustion Engine as the fuel is burned inside the engine in order to work. The mixture of fuel and air is then directed into the Internal Combustion Engine. There are two major components of heat engines 1. Piston and 2. Turbine. The piston is the most common component in the Internal Combustion Engine. These pistons work upward or downward, travelling up and down inside the piston cylinders. For example, most automobiles use four-stroke internal combustion heat engines with an initial start-up stroke, a combustion stroke, a motor stroke, and an exhalation stroke. 

There are different types of Internal Combustion engines. They are as follows.

1. Four Stroke Engine

2. Two Stroke Engine

3. Rotary Engine

External Combustion Engines

ECE or External Combustion Engines involves the method of burning the fuel outside the heat engine and then directing it towards the cylinder with the conduit. In External Combustion Engines, fuel’s chemical energy is transformed into thermal energy and converted into mechanical energy at the final stage. External Combustion Engines is a heat engine with an internal working fluid that is heated by combustion in an external device through the engine wall. This fluid generates motion by spreading and working on the engine’s mechanism. Steam engine in 1760 by James Watt was improvised, converting early steam engines into smaller ones with more efficiency and power. The Steam Engine is a perfect example of External Combustion Engines used in factories, trains, and early ships. These engines are mostly used in power plants. Some of the examples of External Combustion Engines that are currently in use are Nuclear reactors like CANDU reactors, Natural Gas Power Plant, Cold-fired power plants, and more.

Conclusion

A heat engine is a mechanism for converting heat into electrical or mechanical energy to do useful work. In the above article, we have covered the different types of heat engines currently in use. We have discussed the definition of heat engines and the two types of heat engines, i.e., Internal combustion engine and External Combustion engine. We have to go through the meaning of these engines along with the examples. To answer the question, what are the types of heat engines currently in use? ICE or Internal Combustion Engines are currently used by regular people, while scientists or experts use external combustion engines.