Water Injection

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May 16, 2010 | 08:59 AM

#16

gearloose1

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The core theory behind water injection is to lower combustion temperature while providing a medium that expands and as it does so, absorb the heat and convert the energy into work (expansion of gases) that is captured by the motor.

As combustion temperatures are lowered, it is possible to run the engine "hotter" (more fuel used), and improve the specific heat around the flame.

See this fairly well done research paper (funded by Diamler Benz) for the benefits.

http://homepages.cae.wisc.edu/~rutla...00-01-2938.pdf

May 16, 2010 | 09:06 AM

#17

william_04_x

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Just to ramble some more.. The bona-fide EGT reduction is accomplished with water because on a properly setup system, the water molecules enter the combustion chamber with the intake charge. During the combustion process the water molecules change physical state from small liquid particles to vapor. It takes a lot of energy to accomplish this. That energy comes from heat generated by the combustion process. As a result, the temperatures of the exhaust gasses are reduced.

May 16, 2010 | 09:11 AM

#18

gearloose1

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One of the best rationale for water injection is that it lowers emissions.

However, I really don't see many on FTE here pushing for lower emissions on their rig.

May 16, 2010 | 01:36 PM

#19

janton01

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From: Pilesgrove NJ

Quote:

Originally Posted by gearloose1

This is an interesting read regarding water injection. This work seems aimed primarily at reduction in emissions with side benefits to the engine. I am not fond of the idea of injecting water into the pressurized charge after the turbo but I also understand the dangers of mist injection ahead of the turbo. Mine is a stock 03 build engine with only the egr cooler plugged and a coolant filter so I am not working the engine very hard. Biggest job is to pull a 22ft boat on the trailer at about 6700 lb. So far at 102k miles all is working well with the new oil cooler and egr plug done 6k ago. I guess the next project will be the bypass oil filter somewhere down the road as well as a ccv reroute. Thanks for all the input.

May 16, 2010 | 01:43 PM

#20

cheezit

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From: N. Fort Worth, tx

a load of 7k should not really be driving egt to hard. that really not a hugh load and the truck should easly handle it in stock form.

May 16, 2010 | 03:22 PM

#21

janton01

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From: Pilesgrove NJ

Quote:

Originally Posted by cheezit

a load of 7k should not really be driving egt to hard. that really not a hugh load and the truck should easly handle it in stock form.

That's pretty much what I figured, thanks for the advice though. We are off to Hatteras next Sunday so the truck will get a good workout over the 400 or so miles down there. Harpooned the tank a few weeks ago with a nice 6 or so gal increase in capacity. Not easy to singlehandedly remove and replace the center mounted tank but got it done and a nice increase in capacity. Also got the fuel level indicator working fine again but installed another float level switch just in case it fails again. $47 for the gauge and sender from a marine store is good insurance as I sure do not want to take the tank off again. Have a great week.