[Ahmed kandil]

Hello everyone
I'm trying to write an expression for inlet temp with time and this is my expression
0.016[S]*t^6-0.2703[S]*t^5+1.6363[S]*t^4-4.3126[S]*t^3+5.1111[S]*t^2-1.6118[S]*t+298.26[S]
but i get this error
All arguments should have the same dimensions as the first argument [kg^-1 m^-2 s^9 A^2] but argument 2 has dimensions of [kg^-1*m^-2*s^8*A^2]
how i can solve this problem

[rohansharmafree]

You have to adjust the units for all components.
Hence you need adjust the units of each constant.
I am not sure what is this unit [S]

[RavingRaven]

Hi Ahmed,

This thread belongs in the ANSYS Fluent forum, not the CFD freelancers forum.

That being said... Your problem seems to be your units. You mentioned you're specifying temperature, so if you're working with SI units then every term should be in Kelvin (K).

Your formula seems to be a polynomial with different exponents of time - the unit of each coefficient should be K*s^(-n) where n is the power of the temperature term it is being multiplied with and s is seconds. For example, 0.016 * t^6 - here, 0.016 should have units of K*s^(-6) as this will make that whole term equal Kelvin.

[Ahmed kandil]

Hi RavingRaven
Thank you for your reply and i will do this..

[Ahmed kandil]

Hi rohansharmafree
Thanks ...

[Gron1984]

house of hazards

Originally Posted by Ahmed kandil

Hello everyone
I'm trying to write an expression for inlet temp with time and this is my expression
0.016[S]*t^6-0.2703[S]*t^5+1.6363[S]*t^4-4.3126[S]*t^3+5.1111[S]*t^2-1.6118[S]*t+298.26[S]
but i get this error
All arguments should have the same dimensions as the first argument [kg^-1 m^-2 s^9 A^2] but argument 2 has dimensions of [kg^-1*m^-2*s^8*A^2]
how i can solve this problem

If the coefficients are causing the mismatch, you might need to adjust them to ensure they have the correct dimensions. For instance, if your time variable (t) has dimensions of ([s]), then each coefficient should be adjusted accordingly to match the overall dimensions.