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Old   December 1, 1999, 21:52
Default changing reaction rate
Arthur Valais
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Hello All,

Does anyone have any source code snippet on how to alter the volume reaction rate on a per cell basis after each time step or iteration? My guess is to use DEFINE_ADJUST and DEFINE_VR_RATE together but I'm lost after that. Any clues will be appreciated.

Arthur Valais
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Old   December 10, 1999, 11:53
Default Re: changing reaction rate
Joe Maruszewski
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Here's a rather silly example of how you could modify the reaction rate as a function of time. In the example, when a new time step is done the reaction rate is cut in half.

#include "udf.h"

DEFINE_VR_RATE(my_rate, c, t, r, mw, yi, rr, rr_t) { static real old_flow_time = 0.; static real specified_rr = 1.; if (RP_Get_Real("flow-time") > old_flow_time)

specified_rr /= 2.; old_flow_time = RP_Get_Real("flow-time"); *rr = specified_rr; }

If you could be more specific about what you are trying to do I may be able to provide more suggestions.

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