My fill is distilled water and chill charger. At present (separated system) I have a BMW power steering reservoir up front to fill and bleed the system. With the leaky intercooler it appears water leaked in at low boost. At high boost the system was pressurized by the leak and the water was pumped out of the reservoir. (sprayed all over the place under the hood). I have the stock pump and have logged with a supercooler, supercooler and stock H/E in line, stock H/E and now with an E55AMG H/E. The difference in IAT's between all of them is minimal, perhaps 5º. Spraying water meth through the supercharger made little difference in IAT's. Some systems take much longer to reach xº over ambient but they all settled at 20º or above. My next adventure will be an Eurocharged H/E (or the current H/E) with the stock configuration. Anyone have some stock hoses to sell me? I hacked mine and the stockers will make it easier to return it to a shared system.

Les

 

cavitation is a function of many variables, your question is best answered by looking at the vapor pressure of the mixture you wanna use. The fluid boils when the pressure falls below this vapor pressure. The pump has very high shear forces on the fluid, which is how it pumps, this is where the boiling would be most significant.

The series 30 pump would be more powerful and more likely to cavitate. My pet pump the 90 would be WAYYYYY more susceptable to this, but I will be running it at about 1/2 the typical rpm. THiis should work fine as the larger impeller would have less boiling potential.

I have to see the resulting cavitation in the stock IC at the 2 to 4 GPM flow rates ( gotta man up and do this again ). The burning question that I have to quell, is exactly how much static pressure is required to prevent unwanted boiling. My water heater was only about 125 F degrees, the water in the IC may be a bunch higher especially on the edges of the water tubing. Think about under hood temps.........

Woody

 

lessened due to a reduction in the vap prs....
At 212F,
water vap prs. = 14.7psig,
50:50=12.2psig
so 50:50 gives you about 3.5psi extra headroom (in your favour) at 212F.

At 130F (55C) (Wood's test temp) vap prs. water = 2.5psi - so much lower.

The 6lb radiator cap gives you another 6psi headroom = 9.5psi head room over plain water.


I remain a little sceptical about this cavitation issue - only because the pump is not a serious pump
ie: the CM90 is a "small" moderate speed pump with about 4psi output in application. Similar to your fountain pump.
In situ (in the car) - it is seeing a 0.8psi flooded suction.
I'm checking the Net Positive Suction Head Requirements (NPSHr) with lhmarine who are talking to Sweeden.

But have to respect Waldig's experience, "nous" and "optical integrator".

Anyone know the rpm of the CM90?

 

Backup pump data

Lighthouse Marine - Circulation

Lighthouse Marine - Circulation

http://www.lhmarine.co.nz/userfiles/...p%20curves.jpg

The last chart shows the pumps 8+ GPM capacity, dwarfing the 10 and 30.

Got to remember that the pressure on the edge of a automotive pump, Johnson pump, and or boat propeller is durn near a great suction. The boat is cavitating 2' below a lake (1+ PSIG) thats probably 70 degrees F or so and its boiling. Lots of work has gone into the US Sub propeller to keep it from cavitating hundreds of feet below the sea's surface.

Microsoft’s bird’s eye view catches Navy propeller | Ogle Earth

What is Supercavitation?

and finally: Cavitation - Wikipedia, the free encyclopedia

Woody

 

yes - all respects Wood - I understand cavitation - that's probably a little bit of an overstatement considering the inticicies around the phenomenon.

Pumps and propellers are different.
Pumps have a casing, propellers dont.

Hopefully we can find out what the NPSHr is. I exhausted google on it.

 

Will this wake the sleeping bear?

See image attached - I've included both USImperial and SI units

For those not willing to read the original post, Good technique, but it needs to be caveated with the fact that the air was drawn through the IC at what would appear to be a much lower rate than what would be seen on a WOT event.
Based up on the heat the water losses, my guestimate indicates maybe 125cfm versus a WOT which is up around 500-800cfm (depending on your setup).

Not sure what's going on, but I get different results to Woody (all respects).
I think my calcs stand up but am willing to accept counter if there is any err.

The important conclusion I found was for the Series Format IC, when the flow was doubled, the cooling effect increased by 9.8%.
It would be good to do 200-300 cfm or even 500....but we'll see.

---------------------------------------------
For those of us in the minority.....
Lets get a little more techincal....the others can switch off.......yawn....ZZZZZZZZZzzzzzz......
Increasing the flow of air or water, increases the reynolds number.
The water and air heat transfer coefficients are also directly related to their Reynolds number.
That is - increasing the flow, increases the reynolds number which increaes the heat transfer coefficient.
However doubling the flow of water doesnt necessarily double the heat transfer coefficient as shown in the results. In the results, doubling the flow of water only allowed the air to pick up 10% in additional heat.
The same would apply to the air.

It will be interesting to see how this develops.......

Thanks - Waldig/Woody for generating the data - The Mopar and MB communities would be lesser without his brains and energy.

 

Makes sense, I relate it to the NW Intakes. The dual does not double the amount of air flow over the single but it does provide more air. It's up to the individual to decide if the difference between the two is worth the extra time & money, same concept here.

BTW- I enjoy your analytical prowess.

 

Iam in the process of doing the construction and doing the 2000 ft sq. garage. Not sleeping, just doing lots more non car work. Will be back to cars in the winter I would guess. Woody

 

Wow 45x45ft!....lots or room for all your winter toys....!


BTW - I ran my Starmix plastering vac (hi suck) up today - jerry-rigged my home made pitot and a 3" 5D flow tube to the inlet.
With bag filter but no 12 ft hose = 131cfm
With bag filter but no hose = 247cfm
Without bag filter and hose = 305cfm

Note the long hose in Woods original video......I say ditch it.

 

Any updates on the setup with the Johnsson CM90 pump with and without the extra parallell heatexchanger??

 

Mine is on the floor with many other projects, 1930 zenith restoration in process, all planes are grounded, work on dual T/B at a pause, and pump of course. House to be done by august, I have to finish doing the 30 x 66 garage and the heat is really slowing down this 66 yr old dude. working in the rain is a blessing round here. WW

 

Dear Mr. Woodie, Did you ever find out if pressurizing the isolated IC circuit a bit was helpful?

Signed,
A grateful recipient of your magic