SG 1.0 Manometer Fluids Other Than Water?

[Flash]

Tony, That is such a grate idea.

It would take some experimenting on well diameter to get it Right, but it sure would remove all the down falls of H20.

I think the biggest trick, would be finding that House hold/common container, of the exact inside size, for the well.

[Tony]

I think the biggest trick, would be finding that House hold/common container, of the exact inside size, for the well.

It would not be that large a diameter, and something could always be drilled out to the nearest standard required size. It is only the relative exposed fluid surface areas of tube and well that matter.

In the above example, a 25:1 surface area, becomes a 5:1 diameter ratio. A 3mm bore manometer tube might require a 15mm diameter well. At least that might be a good starting point.

Rather than trying to work it all out, a bit of experimentation might be in order.
Build two manometers, one with genuine certified natural water, and the other with your secret magic oil.
Play around with the exposed surface area in the well until both columns placed side by side rise by the exact same amount.

Only potential difficulty I can see with this, might be expansion of the oil with large changes in ambient temperature. Some oils do expand/contract rather a lot with temperature changes. But if you can figure out a fast and easy way to zero your manometer fluid level, (or move the measurement scale up and down) even that should not be an insurmountable problem.

[Flash]

Well I know for sure that the cold weather has "0" affect on Marvel Mystery as i have a scale/gauge, for my velocity probe, with a vary large well, that has not moved from the 0 mark, all winter long were as, my U-Tube with water freeze. and in the 35* to 45* Temperature range actually raise the water a 1/2". Then from there just have to add water do to evaporation.

We will see what happens with MM Oil this summer. So far I'm really liking this fluid.

[stef-1]

Hi,

I've been using the manometer setup page on my Flowcalc sheet and it seems that with DOT 5 brake fluid I would need a 21mm diameter well with my 4mm i.d. tubing to get it to read the same as water (see pic below). It seems the lower the sg of the fluid the smaller the well diameter needs to be.
For now I'll use that Fluorescein in distilled water as it's cheap and I won't have to change my wells. I'm sure it's the food dye or soap that causing it to go gunky. Anyway that should fix it for now. I will look at making new wells and using a different fluid nearer to winter.

It may be a good idea to come up with a list of fluids that people feel work really well along with recommended well/tubing sizes. Would make it easier for newbies to use a fluid they can get easily or find one to work with whatever wells they have?

[86rocco]

Stef, I've not seen that particular spreadsheet before, if you can get it's author's permission, could you post up a copy of it in the spreadsheet forum?

[Tony]

That is what I love about this Forum.
People keep freely adding and sharing ideas, knowledge and experience.
Bit by bit the accumulated wisdom here has grown into an awesome resource.

[stef-1]

Stef, I've not seen that particular spreadsheet before, if you can get it's author's permission, could you post up a copy of it in the spreadsheet forum?

It's a spreadsheet I developed. I did post it up in the old forum but it got lost when the forum crashed and a load of posts disapeared. I'll see if I can post it up tomorrow.

[1960FL]

Can you Euro guy's please help me out (Dumb American here) so maybe i can wrap my head around this problem?

What is the standard test depression you use to test at? is it really 712.7mm? or do you use a different standard?

thanks

Rick

[stef-1]

Most research labs over here test at 10" or 20" of water, same with universities. A lot of the race teams test higher of cause. I see a lot of data over here seems to be normalised to 10" of water.
I test at a minimum of 25" and currently normalise my data to that or 10" depending on the customer. I am still finding what the maximum depression is I can pull on most heads. Once I have a handle on that I will test at a higher standard and normalise to 28". I think 28" is a good world wide standard to normalise to as it seems to be "middle of the road".

[1960FL]

Strf,

I might of been a little unclear also do you read your scale in MM or Inches?

Rick