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April 9, 2015, 22:04 |
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#21 |
Member
sanjeet Limbu
Join Date: Mar 2015
Posts: 91
Rep Power: 11 |
I am trying to simluate the compression stroke by a piston using 2D axisymetric.
Currently i am trial s fo rthe 2D planner mesh using the dynamic mesh - profile mode, I created the profile by using the time and velocity for 1440 points from matlab taking time step as 0.000041667s. But I am unable to get exact mesh motion. I got the zone motion correct. The piston has crevice shape- I made two cellzone- body which defoems and crevice - as moving mesh. I did the following: Cell zone- crevice .set as mesh motion type, and set write profile- having motion history points which also will be used for rigid bodies Piston – as moving wall in boundary condition(piston is of two part its inteface with body and crevice both moving) The dynamic mesh- piston as rigid body- profile selected, Body- as deforming layering only, unchecked the remeshing and smoothening Crevice as rigid body- profile selected. Please tell how to do mesh also move with same distance . I tried the UDF also but that also not working: sjows warning eror unable to read file: #include "udf.h" DEFINE_CG_MOTION(oscillate, dt, vel, omega, time, dtime) { Thread *t; face_t f; /* define the variables */ t = DT_THREAD(dt); /* get the thread pointer for which the motion is defined */ /* if (!Data_Valid_P()) /* return; /* check if the values of the variables are accessible before you compute the function */ begin_f_loop(f, t) /* loop over each face in the zone to create an array of data */ { if (time <= 0.02) vel[0] = (673* time); /* define the velocity of the moving zone---*/ else if (0.02 < time < 0.027) vel[0] = 14; else if (0.027 < time < 0.03) vel[0] = 3 - 2800*(time-0.03); else if (0.03 < time) vel[0] = 0; } end_f_loop(f, t) } |
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April 9, 2015, 22:07 |
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#22 |
Member
sanjeet Limbu
Join Date: Mar 2015
Posts: 91
Rep Power: 11 |
hi iam getting less dynamic motion than the zone motion preview
I am trying to simluate the compression stroke by a piston using 2D axisymetric. Currently i am trial s fo rthe 2D planner mesh using the dynamic mesh - profile mode, I created the profile by using the time and velocity for 1440 points from matlab taking time step as 0.000041667s. But I am unable to get exact mesh motion. I got the zone motion correct. The piston has crevice shape- I made two cellzone- body which defoems and crevice - as moving mesh. I did the following: Cell zone- crevice .set as mesh motion type, and set write profile- having motion history points which also will be used for rigid bodies Piston – as moving wall in boundary condition(piston is of two part its inteface with body and crevice both moving) The dynamic mesh- piston as rigid body- profile selected, Body- as deforming layering only, unchecked the remeshing and smoothening Crevice as rigid body- profile selected. Please tell how to do mesh also move with same distance . I tried the UDF also but that also not working: sjows warning eror unable to read file: #include "udf.h" DEFINE_CG_MOTION(oscillate, dt, vel, omega, time, dtime) { Thread *t; face_t f; /* define the variables */ t = DT_THREAD(dt); /* get the thread pointer for which the motion is defined */ /* if (!Data_Valid_P()) /* return; /* check if the values of the variables are accessible before you compute the function */ begin_f_loop(f, t) /* loop over each face in the zone to create an array of data */ { if (time <= 0.02) vel[0] = (673* time); /* define the velocity of the moving zone---*/ else if (0.02 < time < 0.027) vel[0] = 14; else if (0.027 < time < 0.03) vel[0] = 3 - 2800*(time-0.03); else if (0.03 < time) vel[0] = 0; } end_f_loop(f, t) } |
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