{"id":357501,"date":"2024-03-17T21:54:33","date_gmt":"2024-03-17T21:54:33","guid":{"rendered":"\/forum\/forums\/topic\/pitching-airfoil-using-overset-and-dynamic-mesh\/"},"modified":"2024-04-15T23:24:27","modified_gmt":"2024-04-15T23:24:27","slug":"pitching-airfoil-using-overset-and-dynamic-mesh","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/pitching-airfoil-using-overset-and-dynamic-mesh\/","title":{"rendered":"Pitching airfoil using overset and dynamic mesh."},"content":{"rendered":"

Hi there, <\/p>\n

I am using a ansys to simulate pitching NACA0012 airfoil. I made a rectangular background mesh as in figure 1. then made a O shape mesh to overset on the rectangular background mesh (fig 2). I defined all the cell zones and boundary conditions (velocity inlet and pressure outlet).<\/p>\n

\"\"<\/p>\n

\"\"<\/p>\n

Then I created a compiled udf. given below, <\/p>\n

#include “udf.h”<\/div>\n
#define AMPLITUDE 30.0   \/* Amplitude of pitching motion in degrees *\/<\/div>\n
#define FREQUENCY 2.97  \/* Frequency of pitching motion in Hz *\/<\/div>\n
#define PI 3.14159265359<\/div>\n
 <\/div>\n
DEFINE_CG_MOTION(pitching_airfoil, dt, vel, omega, time, dtime)<\/div>\n
{<\/div>\n
    Thread *t;<\/div>\n
face_t f;<\/div>\n
    NV_S(vel, =, 0.0);  \/*No translational velocity *\/<\/div>\n
   NV_S(omega, =, 0.0);   \/*Initially no rotational velocity *\/<\/div>\n
 <\/div>\n
    vel[0] = 0.0; \/\/ X-direction<\/div>\n
    vel[1] = 0.0; \/\/ Y-direction<\/div>\n
    vel[2] = 0.0; \/\/ Z-direction<\/div>\n
    <\/div>\n
    omega[0] = 0.0; \/\/ Rotation about X-axis<\/div>\n
    omega[1] = 0.0; \/\/ Rotation about Y-axis<\/div>\n
    omega[2] = 0.0; \/\/ Rotation about Z-axis<\/div>\n
 <\/div>\n
    \/* Set the rotational velocity about the z-axis *\/<\/div>\n
    omega[2] = 0.2618 * 18.66 * cos(2.0 * 180 * 2.97 * time);<\/div>\n
 <\/div>\n
  <\/div>\n
}<\/div>\n

now In the dynamic mesh section I did the following.
1. turned off smoothing, remeshing and layering
2. enabled six DOF and enabled motion history (Didnt turn on OneDOF)<\/p>\n

3. finally hooked UDF into the fluid-circle (passive enabled), hydrofoil(passive disabled).<\/p>\n

then used time step of 10^-4. The problem is, the airfoil is not moving and showing same result as steady state case.  \"\"<\/p>\n

Can anyone please help me about this and thell me where I am making the problem? Is it about hooking the UDF or something else?<\/p>\n

<\/p>\n","protected":false},"template":"","class_list":["post-357501","topic","type-topic","status-closed","hentry","topic-tag-fluent-ansys-1"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t