Time step calculation

March 1, 2006, 03:24

Dear all How can we calculate the time stem for a case involving both convection, diffusion buoyancy and combustion. Thank you

March 1, 2006, 07:27

Physically, determining the dominant process, for example,

convection -> delta_t approx delta_x / Vel diffusion -> delta_t approx delta_x deltaX / (2 diffCoef.) ...

and so on, the smallest delta_t is which your need to use.

Mathematically, you can use stability analysis, e.g, Matrix method or Von Neumann's, but it much more difficult depending on the problem.

March 1, 2006, 03:24	Time step calculation	#1
Shashi Guest Posts: n/a	Dear all How can we calculate the time stem for a case involving both convection, diffusion buoyancy and combustion. Thank you

March 1, 2006, 07:27	Re: Time step calculation	#2
al Guest Posts: n/a	Physically, determining the dominant process, for example, convection -> delta_t approx delta_x / Vel diffusion -> delta_t approx delta_x deltaX / (2 diffCoef.) ... and so on, the smallest delta_t is which your need to use. Mathematically, you can use stability analysis, e.g, Matrix method or Von Neumann's, but it much more difficult depending on the problem.

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