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Cannot Construct proper Goal-Seek 4

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Based on this paper (pdf): pubs.ub.ro/dwnl.php?id=CSCC6201604V04S01A0009

I have constructed an Excel sheet to back-calculate CaCl2 w.t% (eq.4) from input density & T using goal-seek. But I am not getting results. Am I doing something wrong?

post-246946-0-13861500-1555499183_ael3ry.jpg

 
Huh???? Your solver came up with the solution that's already there, so what's the problem? I changed your c17 to something else and it calculates the solver solution to be 1389.5

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Thread was marked as Review ...so thnx for reviewing.

I have used the research paper eq. & if according to you my excel construction is OK ...then the answer isn't OK! Because w.t% cannot be >1

Can you download the paper & review the formula I have constructed using the former?
 
Like this -

Capture_qtj6ow.jpg


Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water
 
< 1% is outside the range of 2-40% used to develop the model. Maybe that explains it. Extrapolation.

Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water
 
Latexman
Per research paper....
Using Table.5 & eq.4 I have constructed the spreadsheet. This equation is regressed using data at Table.1 & 2

Take last row & first column of Table.2 for instance ...
Input 288.15 in C14; Input 1286 in C15 ...then try to Goal-seek w.t%
Are you getting answer close to 30%?
 
No, 1.606079195.


Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water
 
^ I think I need to connect to this researcher ...because the number you r producing makes no sense! Am I right?
 
Correct, no sense.

I'd pick a C% and T that is in Table 1 and go thru all the equations by hand to see what's going on. Have you done that?

Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water
 
Latexman
Thanks for reproducing error. Attached is the SMATH sheet ...same result. Now can anyone please produce some resource relating CaCl2 density (specific gravity), T & w.t% ...the only paper that I did find isn't producing results. I operate x3 effect CaCl2 evaporation unit where w.t% is b/w 28 - 60

Screenshot_1_kkt9l0.jpg

 
Latexman, You are the man :)
Please do share how in the God's name you picked this error?
Excellent anyway...
 
40 years of working with dozens, maybe hundreds, of physical property models and correlations.

From Table 1, I used 1173 kg/m3 (20% and 303.15 K) and calculated A1, A2, and A3 from Table 5. Looking at Table 4 at 20%, A1 and A3 were close, but A2 was way off. Since I had been thru the math, I quickly saw if the values of a1 and a2 for A2 was exchanged, then A2 would be close to the value in Table 4 for 20%. So, I exchanged a1 and a2 and it worked well for 20% and 303.15 K. You should check it out for the entire 2-40% range.

Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water
 
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