wet flow bench 2

[Ducky150]

Anyone care to discuss wet flow testing cylinder heads? Seems this is a new topic to talk about with Superflow/Mondello coming out with a kit to add to dry flow benches. Lots of positive feedback so far, I am thinking about building a rendition of it for my 600 bench. Anyone with knowledge of how this unit works care to speak up? Wondering what they do to introduce the liquid into the airstream, sounds like it uses a pump spray it into the airstream. Ideas? D

 

[patprimmer]

I also wondered about the effects of introduced fluids, the ratio they are added at, how critical is distribution and dispersion, how critical is SG, boiling point and vapour pressure, and latent heat of vapourisation of the test fluid vs these properties for the fuel to be used.

Do wet benches just try to incorperate the effects of the introduced fuel on VE or do they try to also predict fuel distribution within the airstream.

I presume a non flamable fluid is used for safety reasons

Regards
pat

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[SMOKEY44211]

About 20 years ago I assembled a flow testing system that enabled me to test wet flow through the engine. Basically it consisted of an assembled engine less pistons and crank. Simply draw a depression through the oil pan with all the conduits in place and you have a flow bench that duplicates the operating conditions of the engine you investigating. What I have just described refers to the intake side. When analizing exhaust flow I would introduce pressure. By using a vacume guage or manometer in the intake side I could tell if I was gaining flow by the vacume readings.Less restriction =lower vacume readings. On the exhaust side a pressure guage would tell the same story. Lower pressure readings =less restriction. By introducing the intended fuel through the carburetor you can now monitor wet flow. (well ventilated of course). Direct port fuel injection it would seem to make this area of study a moot issue. My experience has shown that the vaporization temp. is ultra critcal. Quick example. I had optimized the wet flow of a carbureted V-8 engine using brandX 92 octane gasoline. Egt. readings on the dyno revealed fairly equal flow after much intake manifold reworking in order to achieve this. A switch to VP racing fuel sent the egt. readings all over the boards and a huge loss of power. I don't expect anyone from superflow to agree with my methods as this method side steps any need for thier flow testing products.--------Phil

 

[Ducky150]

I should clarify. What I am talking about is the new "affordable" wet flow attachment that mondello and superflow are selling. You fixture the head so the intake port is flat on the bench and blow thru the intake port with a liquid introduced into the airstream. You have a clear bore tube on the gasket surface of the head and watch the way the liquid comes out into the chamber. Also I guess you have a dye that will show where the wet flow is going in the port.

http://www.superflow.com/newsletters/2003/fall2003/wetflow.htm

this link shows the unit. I am wondering if anyone has seen one in action and can add some insight to how it works. D

 

[MaxRaceSoftware]

one of the good things about Wet Flow Bench is
you don't need to always need to use epoxy in playing with modifications ..you can use real quality molding clay to quickly change shapes in ports , especially chambers
to observe patterns

and since you are blowing thru intake ports , its easier probing with velocity probe and visual viewing, easier access

flow direction and swirl patterns instantly showup
and will varify readings you weren't able to visualize before

Larry Meaux (maxracesoftware@yahoo.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
Support Israel - Genesis 12:3

 

Phil,

I understand your setup, except for the placement of your pressure tappings, can you clearify that point for me?

 

[SMOKEY44211]

For Speedy5. Basically what I described earlier is an assembled engine less pistons and crankshaft. Needless to say it has to be sealed. By tapping into the passage where the oil pressure sensor would normaly go you can read depression or pressure readings as the case may be. My motivation at the time was I was racing in a rules restricted class that only allowed carburetion fueling. I use a burrett placed above the carb that fed fuel to it. By monitoring the amount used over a specific time period wet flow characteristics could be measured. It was a quick and dirty way to investigate flow characteristics throughout the engine in a cost effective (cheap) manner.-------Phil