Challenge

[Cammer]

I have spent much time researching the following concept, and as I am rather long in the tooth, challenge GFN members to investigate this area of engine research.

Low Heat Rejection Engines (LHRE) promise to recoup fuel energy lost to heat in an internal combustion engine. I have not been successful in applying this technology to an SI engine but have shown some potential for a LHRE turbocharged/supercharged diesel engine. A diesel engine rejects about two-thirds of fuel heat energy, one-third to coolant and one-third to exhaust. This leaves only about one-third of fuel heat energy to produce useful power. Gasoline SI engines are less efficient than this. LHRE technology promises great potential for fuel savings. As LHRE engines produce more power, smaller and more efficient engines could be used in place of larger engines. For the performance minded this technology could be used to make serious horsepower. I warn GFN members that this is cutting edge technology and not for the mathematics or physics challenged.

Engineers do not like throwing two-thirds of an engine's power away. IMHO, LHRE shows great potential. If interested in LHRE go to the SAE website and sign up. SAE is a good source of research on this subject.

SAE International

[1989GTA]

I think recovery of some of the exhaust gas/heat technology is already in use. Those would be turbo chargers as stated and power recovery turbines. I think history has shown that the turbo charger is the better route to go.

As to the heat being exhanged with the coolant water/radiator/air maybe that would be in the realm of thermal coatings such as the combustion chamber and exhuast ports and pipes. Progress is being made on thermal barriers but there is a lot of work do to.

So to recap it would seem that the closer the turbo charger is to the exhaust valves the more energy that would be recouped. Again thermal coatings would also help in this regard. As to themal coatings I believe the technology is still in its infancy.

As we know there was a lot of research into ceramics. I don't know the outcome as the companies keep this info pretty close to the vest. Just my thoughts.

[Mr M]

Sounds very complex and hard, what happens if we use something like thallium-doped lead telluride ??