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Thermal Design Solve Block Issues

ptc-4259110
1-Newbie

Thermal Design Solve Block Issues

Hi everyone,

I'm new to this community, but I hope that I can help contribute as well as learn a few things from everyone.

I'm currently working on a project for a class that involves designing the layout of a system that consists of a boiler, pump, and several heat exchangers.

It normally wouldn't be a problem to solve this problem by hand, but because this problem requires multiple pipes and exchangers I am using Mathcad to help automate the process. I've been able to set the constraints for pipe flow, temperature, and diameter; and, trust me, it's been an uphill climb getting all of my syntax correct so that this huge system of equations work.

I've recently tried adding a few extra constraints to help zero in on the actual values of flow rate, temperature, and diameter; but I'm afraid that I cannot get the solve block to find the solution, even if I adjust the CTOL or TOL or change the syntax of the equations.

I'd very much appreciate it if anyone could help me out with my syntax or other issues that I may have overlooked, but I'm fairly new when it comes to complex Mathcad equations and shortcuts. Thank you in advance for your help.

Note: I do not require help with my equations for this project exactly. I just need help formatting them in such a way that Mathcad can solve them. I have several other equations that I need to input, but I have left them out until I can fix the current problem. Also, please excuse the sloppiness of the file. I'm afraid that I did not learn the shortcut to call a certain value in a matrix until I was too far into this project. Thanks.

-Josh Bostick

1 REPLY 1

You are solving for 29 variables with 24 equations and over 30 inequalities. Given..Find looks for an exact solution, which might not exist for the system as you've specified it. Try using Given...minerr instead (just change the word Find to minerr) - or check your equations!

Alan

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