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Diffusion-fluid problem

Posted 13 nov 2011, 18:08 GMT-5 Fluid & Heat Version 4.0a 0 Replies

Nitesh Nama
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Hi I am solving a problem related to the mixing of two fluids (water and CaCl2). In my model the density of the mixture varies as:
rho= A*C+ B*sqrt(C)+ E*(C)^3.5
where A, B and E are constants (dimensional).

I understand that I can use non integral powers to define B and E. However, the model returns an error "trying to evaluate negative power of zero". I believe the model differentiates the equation for some calculations and since C is zero initially, therefore it returns this error. Please suggest how can I solve this. I can't start my simulations from t=0+ as I don't know the value of C at t=0+.

Many Thanks.
0 Replies Last Post 13 nov 2011, 18:08 GMT-5
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Hello Nitesh Nama

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