### Author Topic: Global maximum value of a variable in Fluent using UDF  (Read 8124 times)

#### infocfd

• Newbie
• Posts: 45
• Reputation: +0/-0
• Searching for solution
##### Global maximum value of a variable in Fluent using UDF
« on: September 24, 2020, 05:06:04 PM »
Is there any way of accessing the value of a global maximum value in the domain using a UDF in fluent?

#### william

• Full Member
• Posts: 159
• Reputation: +15/-0
• Know it, share it.
##### Re: Global maximum value of a variable in Fluent using UDF
« Reply #1 on: September 24, 2020, 05:14:20 PM »
Hi,

The Global Maximum Value of a certain variable can be obtained through the User Defined Functions in Fluent using Global Maximum Macro PRF_GRHIGH1(x). This can be used to obtain the Global Minimum as well.

Here is the implementation that outputs the global maximum temperature in the domain:

Code: [Select]
`#include "udf.h"DEFINE_ON_DEMAND(MaxTemp){Domain *d;d = Get_Domain(1); /* Get the domain using Fluent utility */Thread *t;cell_t c;real T_maxx = 0;real T_max = 0;#if RP_NODE{thread_loop_c(t,d){if (FLUID_THREAD_P(t)){begin_c_loop(c,t){T_maxx = MAX(C_T(c,t), T_maxx);}end_c_loop(c,t)}}}#endif T_max = PRF_GRHIGH1(T_maxx);Message("\n T_maxx %0.14f", T_maxx);Message("\n T_max %0.14f", T_max);}`
« Last Edit: September 24, 2020, 05:21:06 PM by william »

#### infocfd

• Newbie
• Posts: 45
• Reputation: +0/-0
• Searching for solution
##### Re: Global maximum value of a variable in Fluent using UDF
« Reply #2 on: September 24, 2020, 05:24:53 PM »
Thanks!