Creating a formula for Hydraulics

[John Holman]

Hi.

I am a not extremely proficient Excel user. I have been trying to figure
out how to tell Excel that I would like to create a formula.

I am trying to create this formula;

FL=C * Q2/100 * L/100
Where;
FL is Friction Loss
C is a varying Coeficient
Q is a varying Quantity in Litres divided by 100(then Squared)
L is Length in Meters divided by 100

C can equal 24.5 for 45mm
C can equal 3.17 for 65mm
C can equal .305 for 100mm

Looking for some help with this formula. For frequent users of excel
creating this formula may be simple, but I have been stumped! I will greatly
appreciate some assistance with this formula.

Thanks in advance.

John Holman

 

[Sheeloo]

Suppose you have one of 45, 65 , 100 in Col A
You have Quantity divided by 100 in Col B
Length divided by 100 in Col C
then enter this in D1
=(IF(A3=45,24.5,IF(A3=65,3.17,0.305))*B3*C3)

 

[Bernard Liengme]

Hello John,

In A1 thru A4, I entered the text: C, Q, L FL (not essential but helpful);
pressed ENTER after each entry
In B1 thru B3, I entered some numbers 24.5, 3, 400
In B4 I typed this formula =B1*(B2^2/1000)*(B3/100) and then pressed ENTER
This gave me the answer 0.882 (check it with your calculator).
Note the parenenthsis are optional here but clarify what is happening.
If you change any number, the value of FL is automatically recalculated.

I will assume you are using a version of Excel before Excel 2007:
Now if you select A1:B4 and use Inset | Names | Create | Left, then for B4
the formula could read
=C_*(Q^2/1000)*(L/100)
Note the C_ rather than C because Excel reserves with name for its own use.

It is unclear what your notes on C mean - want to clarify?

You can do a lot of engineering calculations in Excel. Recommend you buy
either Excel for Dummies or my Science and Engineering book - see my website
(sorry for the crass advert!)

 

[Sheeloo]

I missed the squared part

Use this
=(IF(A3=45,24.5,IF(A3=65,3.17,0.305))*(B3100)^2*(C3/100)

You don't have to divide the quantity and length by 100 before using this
formula