Learning Forum

[azizi0407]

[das.3]

Since your coefficients are constant, why don't you try and incorporate them into the fluid properties. For example: You can increase the density of the fluid to 1.2 times its initial value so that the factor of 6/5 is taken care of in your continuity equation. Next, in order to ensure that the coefficient vanishes in the energy equation, you either decrease cp to 1.2 times its initial value or increase k by the same factor. I know I'm making a wild guess here, but if it works, then you'll save a lot of time with slight effort during post-processing. Would like to know what the experts suggestn

[azizi0407]

Hi, nthanks for the reply and suggestion. Wont it interfere with the results such as Reynolds or Prandtl numbers?n

[das.3]

Yes, it will. But you know the factor by which the Reynolds Number will change. Prandtl number will remain unchanged since change in cp or k will compensate for the increase in density.n

[azizi0407]

Owh. Thanks for the tips.n

[Rob]

Nothing wrong with the suggestions, but I'd be wary of fudging physical properties as that may also alter things like pressure drop if the density isn't constant. You've accounted for the thermal mass by altering cp. nTo the OP, you may be better off explaining what you're doing over posting equations: we're very limited in what support we can offer (read the rules!) so can offer hints and suggestions only if it's not in the manual. n