irrigation water flow rate and nozzle diameter

Most unusual frost/freeze predicted tomorrow. We're looking at winds 18 gusting to 25 with freezing conditions. The strawberries are in bloom.
Standard protocol for still condition frost in strawberry is one sprinkler every 60 feet by 60 feet with a 9/64 nozzle. At 70 psi you get about .1 inch per hour and protection down to 27 or 28. This don't get it for wind, you need a lot more water. There's a convective cooling effect. I need to be in the .3 inch per hour range.
I can double flow by protecting 1/2 the area and running a sprinkler every 30' by 60' spacing. Not quite there. My particular pump will run 40 9/64th sprinklers at 70 psi. I don't know flow rate but its around 125 gallon per minute.
Now for my question, I'm going to run 25 sprinklers on this pump and I need to bore the ID out to match the pumps flow and get 70 psi. What diameter should I try? I can't go smaller once bored, but I have time for two trials. I'm guessing three hours work to remove 25 sprinkler nozzles, bore, replace, and then test pressure.
Karl
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Follow up. If you search google enough you can find most anything. http://www.mcnallyinstitute.com/13-html/13-12.htm
My conclusion from this paper, holding other parameters constant, flow rate varies with the square root of nozzle diameter.
Karl
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Karl Townsend wrote:

Makes sense, but I'd also bucket-test one before drilling them all.
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Bernoulli teaches that flow rate goes with the squair root of pressure and squair of area assuming the nosel factor dosen't change
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CORRECTION squair of area should be squair of diameter
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wrote:

CORRECTION squair of area should be squair of diameter
I went with the slightly different formula I found. it gave an answer of 11/64. I have a bunch of 3/16 nozzles. So I installed every other one and bored a few more to 3/16. Worked out just right with two more changed from 9/64 to 3/16 after the first test. I'm all set for tonight.
Karl
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toolbreaker wrote:

CORRECTION 'squair' is spelled 'SQUARE'.
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