- **Fluent UDF and Scheme Programming**
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- - **udf interpretation successful but does't work**
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udf interpretation successful but does't workHi,
I need to compile a non-uniform heat flux boundary condition on a cylindrical target. The udf has been successifully interpreted in fluent and I can see the functions listed in the menu of the respecting boundary conditions. But after I chose them and run the simulation, the results did not present the effects of the B.C. I wonder if i missed some important set-up or if my udf was wrong in some way. Here are the codes: /*cylinder wall flux*/ #include "udf.h" #define a0 0.2262 #define a1 -0.173 #define b1 0.1471 #define a2 -0.04443 #define b2 -0.04578 #define a3 0.009039 #define b3 0.001342 #define a4 0.002360 #define b4 0.006975 #define w 19.87 DEFINE_PROFILE(outwall_flux1, t, i) { real x[ND_ND]; real l; face_t f; begin_f_loop(f, t) { F_CENTROID(x, f, t); l=x[0]; if(0 <= l <= 0.25) F_PROFILE(f, t, i)= (1e6)*(a0 + a1*cos(l*w) + b1*sin(l*w) + a2*cos(2*l*w) + b2*sin(2*l*w) + a3*cos(3*l*w) + b3*sin(3*l*w) + a4*cos(4*l*w) + b4*sin(4*l*w)); else F_PROFILE(f, t, i)=0; } end_f_loop(f, t) } /*bottom wall flux*/ #include "udf.h" #define a01 0.3031 #define a11 0.02634 #define b11 -0.02008 #define a21 -0.01549 #define b21 -0.01143 #define a31 -0.003358 #define b31 0.005991 #define w1 32.99 DEFINE_PROFILE(Bottomwall_flux2, t, i) { real x[ND_ND]; real y; real z; real r; face_t f; begin_f_loop(f, t) { F_CENTROID(x, f, t); y=x[1]; z=x[2]; r=sqrt(y*y+z*z); if(0 <= r <= 0.1) F_PROFILE(f, t, i)= (1e6)*(a01 + a11*cos(r*w1) + b11*sin(r*w1) + a21*cos(2*r*w1) + b21*sin(2*r*w1) + a31*cos(3*r*w1) + b31*sin(3*r*w1)); else F_PROFILE(f, t, i)=0; } end_f_loop(f, t) } I really appreciate it if someone could help! Best, Haoxin |

Hi,
I'm not really sure if it will work, but maybe try changing the condition in if statement Code:
`if(0 <= l <= 0.25)` Code:
`if(0 <= l && l <= 0.25)` Cheers, kornetka |

Quote:
It worked! Thanks a lot! I could have never realized this small trick on my own ;). Cheers, Haoxin |

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