2. Compression (Reduction of charge volume at constant energy)
As vertex 2 crosses the inlet port, the combustible charge between 1 and 2 gets ‘squeezed’ between the rotor and the housing, thereby resulting in compression.
3. Ignition (Heat addition at constant volume)
While the charge is being compressed, it is ignited by means of a spark. This results in heat generation at constant volume. Due to this, the pressure in the zone enclosed by 1 and 2 also begins to rise, forcing the rotor to move and ‘ease’ out.
4. Exhaust (Expansion of volume at constant heat)
Due to the immense pressure resulting from ignition, the rotor moves to allow for expansion. While 1 and 2 have moved to expand, vertex 3 assumes a position suitable for induction. Meanwhile, the exhaust port between 1 and 2 allows for the expulsion of spent gases, making this a continuous cycle.
Advantages and Drawbacks of a Wankel Engine
When the Wankel engine was developed, as many as 100 manufacturers rushed to implement their own versions of the design. The Wankel rotary engine triumphed over the reciprocating engine for many reasons.
1. Fewer mechanical components, leading to less wear and tear.
2. A Wankel engine can make equivalent power at 1/3 the size of a reciprocating engine, thereby having a better power-to-weight ratio.
3. Overlapping combustion cycles make for superior and smooth delivery of power, while allowing the engine to operate at higher RPMs.
4. A Wankel engine is naturally balanced and does not face problems arising due to unbalanced forces, which is a major problem in reciprocating engines.
5. A Wankel engine, unlike a reciprocating piston engine, cannot seize.
However, despite having many mechanical superiorities, Wankel engines failed to become a mainstream option.