[Jeroen]

Originally Posted by xsrahul

Actually there is latest research on Dual Fuel engines with alternate combustion properties - like Gasoline and Diesel.

This engine christened ‘RCCI’ short for Reactivity Controlled Compression Ignition, was developed at the Engine Research Center at the University of Wisconsin–Madison.

Interestingly it uses the both fuels at different times in the combustion cycle to produce a high thermal efficient (60%) which is higher than Gasoline or Diesel alone.

It is a very interesting development. But they don’t use petrol and diesel. They use gasoline with additives to get a very high octane number, or just plain Hydrogen, BioGas, Ethanol and Methanol.

That is also one of the immediate practical problems. In order to run such an engine, the petrol/diesel infrastructure needs to be updated to accommodate this so called high reactivity fuel, next to existing diesel.

I am not sure how far they are in terms of any practical applications. I have read something about marine medium speed diesel engine being converted to this principle. But as far as I am aware there are some disadvantages that are not so easily overcome. Such as:

• High in-cylinder pressure may cause damage to the engine.
• Fast heat release and pressure rise contribute to engine wear.
• Auto-ignition is difficult to control.
• Constraints at low load.
• Small power range.
• Problems at high load condition because of cylinder pressure restrictions.
• CO emissions are high as compared to the SI engine

The engine design history is full of theoretical great concepts. But for various reasons the theory can be very difficult to put into practice. I am currently building a so called Scuderi engine.

The original Scuderi brief promised:

According to 2007 Scuderi Group claims, tests indicate that the Scuderi engine shows gains in efficiency and reduced toxic emissions over conventional four-stroke Otto cycle designs. The company also says that the Scuderi engine could be used as part of an air hybrid system, allowing recovered braking energy to be stored as compressed air.[10] Laboratory tests of the prototype are said to match earlier predictions generated by computer models.[11]

Source: https://en.wikipedia.org/wiki/Scuderi_engine

However, in practice it was just not possible to achieve those theoretical advantages. It is one of many very interesting ideas, that never worked in practice.

Still, it will make for a very cool, working model, when I have finished my model.



Jeroen

[srini1785]

The company also says that the Scuderi engine could be used as part of an air hybrid system, allowing recovered braking energy to be stored as compressed air.

Does the regenerative braking recovery involve a electric generator+compressor combo?.

[Jeroen]

Originally Posted by srini1785

Does the regenerative braking recovery involve a electric generator+compressor combo?.

To the best of my knowledge only a prototype of this engine exists and was only run for some trials.

There is a company that has developed another number of patents where they use the scuderi engine to act as a compressor too, storing energy. But as far as I know all of this are all just patents.

http://www.scuderigroup.com/

Apart from that one protype, nobody has actually build this engine.

One of its biggest drawbacks is mechanical losses.

Jeroen

[Jeroen]

This just showed up on my YouTube feed. Another “revolutionary” engine design that did not make it past several pro types.

https://youtu.be/GI9pkcFJXV4