I like rotary engines, and when I heard about the fabled "Rotapower" engine I had to do some digging. One of the marketing claims of the Rotapower is an efficient coating that reduces fuel consumption - Quite a claim, so I went a little deeper and found the NASA Contractor Report (#195445, which I've uploaded here but you can find it online) of the coating they use, called PS200.
It's a very interesting read, and I highly recommend you check it out if you're interested in the research. The portion that interests me the most comes from the conclusion section on page 8;
1.) The use of a TBC [Thermal Barrier Coating, aka PS200] on the side-walls with an iron rotor reduced specific fuel consumption (SFC) by 8.6%. Using TBC on both the side-walls and the rotor face of a titanium rotor reduced the SFC by 16.1%
16% is a big difference in fuel consumption. This study was done in 1995, when computerized coating tech wasn't nearly as precise as it is today; According to the paper, a more uniform surface than they could achieve would give even greater gains. So I guess these are my questions;
Would adding a thermal coating to a production piston engine achieve similar results? Is ~15% better fuel burn enough to make people consider overhauling their entire engine?
Do you think modern coating techniques could achieve a better uniform surface, maybe even further reduced SFC?
It's a very interesting read, and I highly recommend you check it out if you're interested in the research. The portion that interests me the most comes from the conclusion section on page 8;
1.) The use of a TBC [Thermal Barrier Coating, aka PS200] on the side-walls with an iron rotor reduced specific fuel consumption (SFC) by 8.6%. Using TBC on both the side-walls and the rotor face of a titanium rotor reduced the SFC by 16.1%
16% is a big difference in fuel consumption. This study was done in 1995, when computerized coating tech wasn't nearly as precise as it is today; According to the paper, a more uniform surface than they could achieve would give even greater gains. So I guess these are my questions;
Would adding a thermal coating to a production piston engine achieve similar results? Is ~15% better fuel burn enough to make people consider overhauling their entire engine?
Do you think modern coating techniques could achieve a better uniform surface, maybe even further reduced SFC?