Some question about water/meth injection

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nilsson

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Hello.
Have some question about water injection.

When you add water, will the amount of exhaust gas increase (volume) due to water steam, or decrease due to cooling effect?

If it decrease, than will it help a smaller exhaust housing to give less drive pressure?
If it increase, than will it help a bigger exhaust housing with spool-up?

Is it worth the extra money to buy a system that will be trigged of egt?

How did a proggresive system work? The pump isnt variable or? It give maximum as soon its trigged? Is it with mor injectors that is trigged with different boost settings?

Hope some can help me a little:)
//nilsson
 
a progressive controler starts to inject water at a lower amount of boost and then will kick in full water at a higher boost.

what i was told buy several venders that i talked to when i was looking to get watermeth. they told me just get a boost controller cuz egts dont work the best on turbo diesels. because you need to have boost to make the water work or it will just snuff out the motor. so i would just save a little money and get a progressive boost controller
 
Have a got this right:

A simple system use a check valve that opens when the pump is trigged by boost, and the pressure in the line overcom the spring in the check valve?

A progressive sysem use a solenoid that the controller open and close, in different duty cycle depending on boost?

No system use a waterinjector in the intake, like a coldstart in a gasser. Water always enter the intake in an nozzle, from electric.

//nilsson
 
Nilsson, a simple system can use a solenoid or check valve to control flow.
Most progressive systems use a check valve or solenoid to control the flow, and the pump is turned on and off at different duty cycles. Aquamist, Coolingmist for about 2 weeks?, and FJO maybe, used a high speed valve to meter flow similar to an injector, by leaving the pump either always turned on, or activating with the injector or before injection began.
 
But all systems use pwm-control of the pump, not pulsing injectors ?
//nilsson
 
It's simple to make the amount less at lower boost, just limit the voltage to the pump and it runs slower, all performed by a controller.

Jim
 
Only Aquamist currently pulses the solenoid(injector), the rest pulse the pump
 
nilsson said:
When you add water, will the amount of exhaust gas increase (volume) due to water steam, or decrease due to cooling effect?
Click to expand...
It will increase because you're burning the methanol. There is no "steam effect".

Is it worth the extra money to buy a system that will be trigged of egt?
Click to expand...
No.

How did a proggresive system work? The pump isnt variable or?
Click to expand...
Pulse width modulation to the valve. The pumps all vendors use is a simple on-off triggered by line pressure.
 
Nillson, the water will still expand to the 1200X or whatever the phase change does, as well as the burning methanol, thus adding to the exhaust gas
Tormentor, only aquamist currently pulses a valve. I haven't read of anyone running an Aquamist kit on a diesel in the US. They've just this year gotten the tech up to speed to keep up with the injector rates as well as pump pressure.

You can argue that others do as well, but only Devil's Own has a pulse width that a normal valve would be able to handle. They pulse the pump as well, so it's a moot point.
 
Last edited:
dust said:
Nillson, the water will still expand to the 1200X
Click to expand...
No it wont. The cylinder has over 400psi in it, that "1200x" is for the open atmosphere. At a volume of water injected that doesn't quench combustion, it adds less than 1psi to cylinder pressure. The combustion of methanol is what measurably increases power to the wheels. The small change with raw water is from increased air density.
 
Tormentor, where are you getting your info from? I haven't read about this before.
 
Whats hard about it? A student doesn't have to master every aspect of them, they just need to know the basics. Just like somebody that passes 12th grade English doesn't have to be a literary master to get an A.
 
It's been a few weeks since I was in high school, but I just don't recall a lot of thermodynamic and fluid dynamic talk back then.
 
Biology, chemistry, physics, etc. If there was any thermo or fluid dynamics, I don't remember it being classified as such.
 
im taking thermodynamic class in the fall at UCF in my quest for mechanical engineering degree. now back on topic i heard water meth doesnt really bring down egts to much just add 40-50rwhp
 
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