# Thread: The most complete compendum of P/Q graphs. (BIG)

1. ## The most complete compendum of P/Q graphs. (BIG)

LOOK HERE FOR THE GRAPHS

I don't have enough post at the top to stuff everything in here.

2. All Graphs; ALL.

P/Q, ALL
________________________________________________

Pump Efficiency (pip/pop) [ Greater than 4M head]
________________________________________________

Overall Pump Efficiency (eip/pop) [ALL]
________________________________________________

Point of Best Efficiency, ALL

3. whew! nice. the comparison between tube sizes and flow rates is helpful. thanks.

4. whew!? Tell me about it. I spent three full days working on those bad boys.

5. Originally posted by UberBlue
whew!? Tell me about it. I spent three full days working on those bad boys.
Well done.
Data manipulation and graph presentation is a thankless chore.
However using Watts~ m(H2O)x lpm/6 did a rough check on a couple of values:-
MCP1200 @ 10 lpm & 8.6m(H2O), W~ 14.3w.
Eheim1048 @ 5lpm & 5.1m(H2O), W~ 0.9w

Arithmetic error?

6. Wow thats very useful!

This is Uber Sticky meterial.

7. Originally posted by Les56

Well done.
Data manipulation and graph presentation is a thankless chore.
However using Watts~ m(H2O)x lpm/6 did a rough check on a couple of values:-
MCP1200 @ 10 lpm & 8.6m(H2O), W~ 14.3w.
Eheim1048 @ 5lpm & 5.1m(H2O), W~ 0.9w

Arithmetic error?
I dunno. My math skill are quite horrid. I can plug stuff into a formula and that's about it.

I went about things the long way and used the formula-

P = Q*H*s/366

Where:

Q = flow rate in M^3/h
H = total head in meters
s = specific gravity
P = water horsepower

Then it was a simple matter of converting wHP to watts. 1 wHP = 746.043 watts.

(0.6m^3*8.58Mh*1)/366 = 0.014065574wHP = 10.49352285watts

Thank god for Excel.

Since you're the math guru, want the source data?

EDIT: This just dawned on me. The water block resistance curves and the pump P/Q's intersect at the same flow rates on both types of charts. If the PBE data was bad, that wouldn't be the case.

8. Originally posted by UberBlue
......
Since you're the math guru, .............................?
...
I am not a "math guru".
I just do sums on beer-mats with the aid of a calculator(misplaced slide rule).
However I suspect the equation is wrong:

My "beer-mat" version:-
= 2.006 x Head(mH2O) x Flow(m^3/h)
Power(Horsepower) = 2.006/550 x Head(mH2O) x Flow(m^3/h) = 0.00365 x Head(mH2O) x Flow(m^3/h)

9. Great work ^_^.

10. Awesome job UberBlue. I vote sticky, great graphs to use as a reference.

11. Originally posted by Les56

I am not a "math guru".
I just do sums on beer-mats with the aid of a calculator(misplaced slide rule).
However I suspect the equation is wrong:

My "beer-mat" version:-
= 2.006 x Head(mH2O) x Flow(m^3/h)
Power(Horsepower) = 2.006/550 x Head(mH2O) x Flow(m^3/h) = 0.00365 x Head(mH2O) x Flow(m^3/h)
Ahhh! My brain, it's tingling.

And you're being modest. I've seen some of the work you've done @ procooling.

The equation I used is a pump industry standard. A couple of people "who are in the know" about pumps checked my preliminary math and verified it correct.

There are two versions of the equation I used, one for metric units and one for US units. And there is a slight difference between water horsepower and brake horsepower.

Like I said, about the extent of my math ability is plugging numbers into an equation. I can find the equation I need and interpret the output of it, but as to what the equation is actually doing, it's usually beyond me. Like the "366" in my equation. I have no idea what that is. I just know I have to divide by it.

12. Thats awesome.

What graphing software did you use for that? I could use that for my math class next semester.

Thanks.

13. Originally posted by 9mmCensor
Thats awesome.

What graphing software did you use for that? I could use that for my math class next semester.

Thanks.
Microsoft Excel. It's all about the formating.

14. Originally posted by UberBlue

Microsoft Excel. It's all about the formating.
Wow, those are the Best Excel graphs I've ever seen. Mine always look like junk : (

15. There is nothing on an Excel graph you can't change with a right click.

16. nice work

17. wow... nice job there UberBlue...

*cough*give dis man a sticky!*cough*

18. Thanks for the kind words.

They're going to get better. I hopefully belive I have a crap load of radiator and waterblock data to soon put on there.

19. Now what would be nice would be an interactive calculator and grapher.

Select the waterblock from a drop-down menu
Select the pump from a drop-down menu
Select the fan(s) from a drop-down menu
Assume 2m of 1/2" tubing

A whole mass of values and PQ curves comes out.

Of course this requires engineering level data for the devices in question.

20. i can do that in C++ but of course it would be in a dos console.
actually made a very similar program that does the same thing but with machine productions for numbers in my 'programming for engineers' class, hehe. give me the tables and you'll get a program.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•