You are currently viewing our forum as a guest, which gives you limited access
to view most discussions and access our other features. By joining our community, at no cost, you will have access to start new topics, reply to conversations, privately message other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join RX7Club.com today!
Has anyone powered a turbo by liquid rocket fuel instead of engine exhaust?
So I was just trying to think of how you could have a turbo or supercharger without the exhaust backpressure or parasitic drag for a very high horsepower application.
Perfect for high overlap applications like a peripheral ported rotary.
Easiest to do with common automotive components would be to power a large turbo with the addition of a cast iron combustion chamber incorporating a spark plug and nitrous oxide and gasoline injection.
I remember reading about a company in the 60s (Turbonique) that started by making N-Propyl Nitrate fueled positive displacement superchargers and ended up instead just making a 1,000hp liquid rocket fueled turbine section integrated into the differential 3rd member to augment engine power.
I guess they had a little problem blowing up especially if you turned it on and off and back on as the monopropellant would tend to pool in the combustion chamber...
This ad is not displayed to registered or logged-in members. Register your free account today and become a member on RX7Club.com!
I thought you were joking at first. You could always use a hydrogen rocket to spin it, it would be much more stable to turn it on and off. Here is a video of a hydrogen peroxide powered turbine in a go kart, hopefully yours wont turn out the same way
Well, I guess if you are going to power your centrifugal supercharger (turbo) with gasoline and nitrous oxide it begs the question on why not just inject that gasoline and nitrous oxide right into the engine?
Good question. I don't know.
I have seen internet claims of 1,000+HP 2 rotors, 3 rotors and 4 rotors, but never 1,000+HP all nitrous oxide rotary.
Is it just because no one is trying? I doubt that!
Or is there something inherently more reliable about forced induction?
Is it the fact that a turbo charger cushions the apex seal in the groove as it is slapped from side to side with boost pressure in the intake cycle and exhaust backpressure in the exhaust cycle to offset the higher pressures of making more power in the combustion cycle?
Or is it that with a 1,000hp shot of nitrous oxide it is hard with current systems to get the mixture precise enough for normal combustion?
Well, I guess if you are going to power your centrifugal supercharger (turbo) with gasoline and nitrous oxide it begs the question on why not just inject that gasoline and nitrous oxide right into the engine?
As you said. . .no backpressure. Significantly less backpressure means lower EGTs and cooler engine bays. Additionally, with a relatively simple injection controller, boost by speed or RPM or any other parameter could easily be regulated without wastegate springs or boost solenoids. There are likely other benefits as well if we brainstorm on it a bit more.
Now, is it worth it for the added weight/complexity? That's another question.
__________________
1993 CYM stock-port GT42R 20B
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Quote:
It's a matter of quantum physics and black holes. You obviously do not understand how a treadmill works.
[FS] To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
I thought of converting to a jet with just some of the compressor output backfed to keep the turbine section going with gasoline.
That would be good for a class that doesn't allow Nitrous Oxide or only allows one power adder (though in a one power adder class you could argue the n2o is just part of the fuel for your one power adder since the engine doesn't ingest it directly).
One problem is have you seen how difficult it is to get those turbo based jets going? I guess you would have to have it plumbed to the engine like a normal turbo, get it spooled, turn on an antilag system and then bypass the engine exhaust around the turbo.
Lots of complexity.
There may be enough energy available from putting a simple "pulse jet" on the turbo exhaust side, but I doubt it.
Yep, Startup is difficult. I don't think it would be practical as an on off setup.
.
Quote:
Originally Posted by BLUE TII
I thought of converting to a jet with just some of the compressor output backfed to keep the turbine section going with gasoline.
That would be good for a class that doesn't allow Nitrous Oxide or only allows one power adder (though in a one power adder class you could argue the n2o is just part of the fuel for your one power adder since the engine doesn't ingest it directly).
One problem is have you seen how difficult it is to get those turbo based jets going? I guess you would have to have it plumbed to the engine like a normal turbo, get it spooled, turn on an antilag system and then bypass the engine exhaust around the turbo.
Lots of complexity.
There may be enough energy available from putting a simple "pulse jet" on the turbo exhaust side, but I doubt it.
__________________
Chris
1993 FD3S R1
1975 Suzuki RE5
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
That's the money you could be saving if you didn't own a RX-7.
Last edited by FixableUnknown; 09-02-09 at 08:23 AM.
Reason: .
There was a version of the Turbonique Drag Axle , that was like a second pinion assembly bolted in place of the ring gear cover. (The one shown is on a Halibrand quick change diff centre section), with nothing less than a thermolene powered rocket nozzle mounted to the diff.
At the touch of a button, it would add an extra 1,300 horsepower.
Another they had for sale was an adapter for that rocket motor onto a VW transaxle as used in their "Black Widow" drag car that took flight running 9 sec 1/4 mile at 160mph.
The wreckage of that VW with a testimonial from the driver was one of their advertisements- lol.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. href=" To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. target="_blank">Celebrate February 1st, the 50th anniversary of a running rotary!
Yes! That is about the kind of idea I had and for the same reason, but an APU is slow to start. That is what had me thinking about a fuel and oxidizer.
Since a gasoline and N2O powered supercharger would be light with LOTS of power potential it now becomes feasable to create...
a centrifugal NEGATIVE supercharger using a turbo or (turbos) built with 2 hotsides to suck the exaust out of the engine further increasing VE.
The concept is for a class that allows forced induction and nitrous oxide you now have supercharging independent of engine horsepower and negative supercharging available independent of engine horsepower at only a slight weight penalty.
That would really kick up the VE on a properly ported rotary!