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Value of ‘x’ to find analytical solution
Posted by Mohammed Sadique on December 8, 2023 at 6:25 pmThis is the example 5.1 from the book versteeg malalasekara, To find the analytical solution need the value of ‘x’ can anyone please tell me the value of x.
Rahul replied 4 months, 1 week ago 2 Members · 4 Replies 
4 Replies

Dear Mohammed Sadique,
Please check the question for the example (Example 5.1). It is very clearly given in the question and the images(Fig. 5.2 and 5.3) provided that x is the distance of the node and ranges from 0 to L. Please go through the questions thoroughly to understand all terms correctly.
Best regards
Flowthermolab support 
Hi Rahul…
When you going to calculate the analytical solution there phi(x)=2.7184exp(x)/1.7183 here I put x value the distance also given in table but answer is not matching? That’s why ask is x value is different or calculate from another formula or equation.

Hi Mohammed Sadique,
I have tried using the same equation and I am getting the same values up to about 2 decimal places. If you are getting very different results, please check the implementation.
I got the exact same values using Google sheets up to 4 decimal places, but was correct only up to 2 decimals in Excel. The difference may be due to different implementations of e^x in both packages or significant digits associated with the values of e. So if the answer is similar up to 2 decimals it should be ok.
Also, when posting queries in the forum, it would be better if you could explain the issue in the first post itself so that we can help you better. It would be difficult to answer generic questions without getting an idea of the issue first.
Best regards
Rahul
Flowthermolab

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