[Mr.Rioes]

Hey there,
I am writing a UDF for parallel computing at the moment.
I am using the Compute_Force_And_Moment function. But I am not sure if I need to adjust the use of it in parallel processing.

Since i didn't find much information on the web i wrote this function, with which i will investigate how the function works.

#include "udf.h"

#define area_factor 2.01713

DEFINE_EXECUTE_AT_END(parallel_force)
{
int force_fluid_domain_id;
int force_boundary_id;
real force_gas_x = 0.0;
real force_gas_y = 0.0;

#if !RP_HOST
Thread *t_force;
Domain *force_fluid_domain;
real body_force[ND_ND], moment[ND_ND], cg[ND_ND];
#endif

#if !RP_NODE
force_fluid_domain_id = RP_Get_Integer("input/force_fluid_domain_id");
force_boundary_id = RP_Get_Integer("input/force_boundary_id");
#endif

host_to_node_int_2(force_fluid_domain_id, force_boundary_id);

#if !RP_HOST

force_fluid_domain = Get_Domain(force_fluid_domain_id);
t_force = Lookup_Thread(force_fluid_domain, force_boundary_id);

Compute_Force_And_Moment(force_fluid_domain, t_force, cg, body_force, moment, TRUE);
force_gas_x = body_force[0] / area_factor;
force_gas_y = body_force[1] / area_factor;

Message("\nForce X on Node %d before adding: %f N\n",myid,force_gas_x);
Message("\nForce Y on Node %d before adding: %f N\n",myid,force_gas_y);

#if RP_NODE
force_gas_x = PRF_GRSUM1(force_gas_x);
force_gas_y = PRF_GRSUM1(force_gas_y);
#endif

#endif

node_to_host_real_2(force_gas_x, force_gas_y);


#if !RP_NODE
Message("Force X after adding over nodes: %f N\n",force_gas_x);
Message("Force Y after adding over nodes: %f N\n",force_gas_y);
#endif

}

What I want to do with this function, is to see if the area on which the force gets calculated is split between the nodes.

But when I start the calculation, fluent calculates the force but only prints the last two messages to the console. And afterwards i get an error. This is what is printed to the console:
riting "| gzip -2cf > SYS-26-00000.dat.gz"...
Writing temporary file C:\\Users\\jensb\\AppData\\Local\\Temp\\flntgz-91683 ...
Done.

Force X after adding over nodes: 7.781368 N
Force Y after adding over nodes: 120852.712844 N
Error at host: floating point exception
MPI Application rank 0 exited before MPI_Finalize() with status 2

Why do I get the floating point exception error ?