Calculate a purge or flow rate

sdm1980

New Member
Joined
Aug 28, 2014
Messages
2
Hi everyone, somewhat new to using excel.
So here's the problem I am having

I am trying to calculate a flow/purge rate from water being purged from a well

10:43am static water level (SWL) was 7.82m known purge rate of 8LPM (litres per minute)
10:46am SWL was 7.87m purge rate ?
10:49am SWL was at 7.9m, purge rate ?
10:52am SWL was at 7.925m, purge rate ?
10:55am SWL was at 7.962m, purge rate ?
10:59am SWL was at 8m, purge rate ?

What I would like to do is have a formula that automatically calculates the change in purge rate. Any information would be greatly appreciated
 

Excel Facts

Can a formula spear through sheets?
Use =SUM(January:December!E7) to sum E7 on all of the sheets from January through December
If water is being purged from the well, surely the level should be decreasing :confused:

There is inadequate known information to create a formula.
 
Upvote 0
the level is top of casing to water level, so picture if you were standing over a sump/pool/etc. and taking a measurement from there. as you take more water out the measurement of the water level will increase.

well parameters are as follows
well diameter: 2 inch diameter
volume/meter: 2.024 L
total depth of well: 26.64
static water level before purge starts: 7.59m
H2O Length: 19.05m
well volume: 38.5572L
 
Upvote 0
Don't you need to know how much water is flowing into the well? And doesn't that depend on the height of the water column?

Or does the purge pump's volume just vary inversely with SWL?

Or ...??
 
Last edited:
Upvote 0
If I understand this correctly then the formula structure should be

=((PI*(Raduius^2)*(current level - previous level)*1000)/((current time stamp - previous time stamp)*1440)

The multiplier of 1000 converts the initial calculation from cubic metres to litres. The multiplier of 1440 is to convert the decimal value of the time difference to minutes.

With times in column A and water levels in column B

=((PI()*(0.0254^2)*(B3-B2))*1000)/((A3-A2)*1440)

Should return the rate of litres per minute.
 
  • Like
Reactions: shg
Upvote 0
You're my hero if that's correct.
 
Upvote 0

Forum statistics

Threads
1,213,543
Messages
6,114,238
Members
448,555
Latest member
RobertJones1986

We've detected that you are using an adblocker.

We have a great community of people providing Excel help here, but the hosting costs are enormous. You can help keep this site running by allowing ads on MrExcel.com.
Allow Ads at MrExcel

Which adblocker are you using?

Disable AdBlock

Follow these easy steps to disable AdBlock

1)Click on the icon in the browser’s toolbar.
2)Click on the icon in the browser’s toolbar.
2)Click on the "Pause on this site" option.
Go back

Disable AdBlock Plus

Follow these easy steps to disable AdBlock Plus

1)Click on the icon in the browser’s toolbar.
2)Click on the toggle to disable it for "mrexcel.com".
Go back

Disable uBlock Origin

Follow these easy steps to disable uBlock Origin

1)Click on the icon in the browser’s toolbar.
2)Click on the "Power" button.
3)Click on the "Refresh" button.
Go back

Disable uBlock

Follow these easy steps to disable uBlock

1)Click on the icon in the browser’s toolbar.
2)Click on the "Power" button.
3)Click on the "Refresh" button.
Go back
Back
Top