[franc1]

Hi everybody,
i need a UDF for the time-step in which i have to assign 3 different time-steps at 3 different levels, respectively:
from 0 to 1s ---> TS=0.01
from 1s to 3s---> TS=0.004
from 3s to end---> TS=0.1

I tried this way but it didn't work

#include "udf.h"

DEFINE_DELTAT(ts, d)
{
	real time_step;
	real flow_time = CURRENT_TIME;
	if (flow_time < 1)
		time_step = 0.01;
	if (flow_time > 3)
		time_step = 0.1;
	else
		time_step = 0.004;
	return time_step;
}

Thank in advance

[p.b+cfd]

Try this:

DEFINE_DELTAT(ts, d)
{
    real time_step;
    real flow_time = RP_Get_Real("flow-time");

#if PARALLEL
    host_to_node_real_1(flow_time);
#endif

    if (flow_time < 1.0)
    {
        time_step = 0.01;
    }
    else if (flow_time > 3)
    {
        time_step = 0.1;
    }
    else
    {
        time_step = 0.004;
    }

    return time_step;
}

But I guess you have to compile it!