[niky]

Originally Posted by Grant-53

Running diesel engines on natural gas is getting serious attention for the bus fleets in north central Pennsylvania as natural gas is cheap there. GE put out bids for injectors to convert their locomotive engines to natural gas. Hydrogen is a highly volatile fuel and so is prone to pre-ignition; not something useful in a turbo diesel.

Propane injection works a treat with diesels. In blended use, due to how cheap propane is, you can save a whole lot.

Originally Posted by smallscaleH2

Not into the exhaust, over the exhaust. The idea is that the exhaust gas would wash out due to the water, in plain air. This is important as in plain air, there's no waste heat from the tailpipe itself, so it's easier to wash it out.

You're going to spray past the tail-pipe? That means the least improvement per gallon of water used.

Originally Posted by smallscaleH2

I'll try a gravity-fed system first, seems simpler if I can get it to work.

Simple, un-metered, and erratic.

Originally Posted by smallscaleH2

Well, no. There's the heat issue mentioned above. Also, if I do it at the exhaust, the sprayer doesn't need to resist the heat either, so many of the parts can be plain plastic then.

Heat, true. Which is why the original suggestion was for intake injection. Injecting a water mist right after the air intake or before the turbo is best.

Originally Posted by smallscaleH2

Agreed. But this method is just a quick fix for Diesels and intented to improve air quality with these since I can't run fully on hydrogen in Diesels (hydrogen injection will work, but that's still more polluting than running on pure hydrogen). So the idea is that I get the hydrogen injection implemented first, and then make sure that much less (preferably none) of the generated air pollution gets into people's lungs.

First, do what's proven to work.

Understand how and why it works.

Nobody injects water into the exhaust. There's a good reason for that. A lot of racers and diesel tuners use it. There's also a good reason for that.

Also, a water injection system is already half of what you need to transition to a hydrogen system, if you still choose to go there.

And it works. It really works. I've had two or three installed. Race teams use them. Manufacturers have experimented with them, but don't use them because they don't trust consumers to refill the water properly.