Specifications

Constant Volume Heat Addition allows faster combustion to take place resulting in higher temperatures with minimum fuel. More work is produced because of the earlier expansion of gases and a dull power stroke with entire fuels energy converted to mechanical energy, and since the surface area is lower in combustion, less heat is lost to the surroundings.

Constant Volume Heat Addition is achieved by increasing the width of one of the rotor’s lobes. Constant Volume Heat Addition increases the efficiency of the engine by giving it 20-30% more power, whilst using the same amount of fuel. This high efficiency of the engine also significantly decrease CO₂ emission (by 50%), thus making this engine eco-friendly.

A higher expansion ratio is achieved by optimising all 4 stages of the Atkinson cycle within the engine for better efficiency.

1. Since the intake and exhaust sides are separate, the intake side is cooler than the exhaust side and less heat is transferred from the rotor to the intake charge. This means there will be less back pressure and as a result higher volumetric efficiency. Since the charge is cooler a higher compression ratio can be achieved.
2. Constant Volume Heat Addition means ignition before the compression stroke ends is not necessary, meaning there will be no back pressure due to early combustion. During ignition and Constant Volume Heat Addition the volume of charge is low resulting in faster flame propagation thereby improving combustion results.
3. Anyoon has a high initial torque in each power stroke as most of the heat energy is converted into mechanical work earlier and therefore less heat will be transferred to the surroundings. In addition the expansion ratio is increased without changing the compression ratio, thus more heat will be converted to work.
4. The engine's exhaust stroke is almost equal to the atmospheric pressure due to a higher expansion ratio and no valve opening is required before the expansion stroke ends, therefore reducing exhaust blow down loss. This results in less back pressure during exhaust without losing any power in expansion stroke. The higher expansion ratio gives a 10% improvement in efficiency.

Internal cooling by water injection is a waste energy recovery system. Water injection inside combustion chamber for cooling is more suitable to the new concept rotary engine than existing piston engines because of the implementation of Constant Volume Heat Addition. When combustion ends, water is sprayed into the combustion chamber, the high temperature vaporises and expands the water. This cools down the combustion chamber and gases, and reduces the exhaust temperature. Therefore lost heat energy is reduced as it is converted to more work by converting water to steam and increasing the pressure of steam and gas. In addition, since the combustion chamber was cooled faster and efficiently the compression ratio and combustion temperature are increased to get maximum efficiency. Even though specific heat of water is higher than exhaust gases, the advantage of possibility of higher combustion temperature and reduction in cooling overhead overshadows this disadvantage. Optimum time and duration of water injection during expansion stroke is programmed via an Electronic Control Unit.

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