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March 15, 2016, 11:41 

#41  
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When applying Discrete*Population Balance Model in ANSYS Fluent we have to put predefine boundary conditions values. For Example, phase.. Air.. Bins...7 Ratio Exponent...1.7 Minimum Dia...0.05cm then in boundary conditions... Velocity Inlet...Boundary Values*for setting*are.. Bin0fraction________ * Constant Bin1fraction_________ Constant Bin2fraction_________Constant Bin3fraction_________Constant Bin4fraction_________Constant Bin5fraction_________Constant Bin6fraction_________Constant How to set these values to get appropriate gas distribution ? How to set boundary condition values in Fluent Population Balance model ?  ResearchGate. Available from: https://www.researchgate.net/post/Ho..._Balance_model [accessed Mar 15, 2016]. 

March 15, 2016, 11:48 

#42  
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Quote:
When applying Discrete*Population Balance Model in ANSYS Fluent we have to put predefine boundary conditions values. For Example, phase.. Air.. Bins...7 Ratio Exponent...1.7 Minimum Dia...0.05cm then in boundary conditions... Velocity Inlet...Boundary Values*for setting*are.. Bin0fraction________ * Constant Bin1fraction_________ Constant Bin2fraction_________Constant Bin3fraction_________Constant Bin4fraction_________Constant Bin5fraction_________Constant Bin6fraction_________Constant How to set these values to get appropriate gas distribution ? How to set boundary condition values in Fluent Population Balance model ?  ResearchGate. Available from: https://www.researchgate.net/post/Ho..._Balance_model [accessed Mar 15, 2016]. 

March 15, 2016, 11:57 

#43  
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Quote:
When applying Discrete*Population Balance Model in ANSYS Fluent we have to put predefine boundary conditions values. For Example, phase.. Air.. Bins...7 Ratio Exponent...1.7 Minimum Dia...0.05cm then in boundary conditions... Velocity Inlet...Boundary Values*for setting*are.. Bin0fraction________ * Constant Bin1fraction_________ Constant Bin2fraction_________Constant Bin3fraction_________Constant Bin4fraction_________Constant Bin5fraction_________Constant Bin6fraction_________Constant How to set these values to get appropriate gas distribution ? How to set boundary condition values in Fluent Population Balance model ?  ResearchGate. Available from: https://www.researchgate.net/post/Ho..._Balance_model [accessed Mar 16, 2016]. 

April 6, 2016, 04:06 

#44  
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In a bubble column reactor two fluid air/ water is used. From the experiments and literature survey we*came to know the Mean Diameter is 4mm. Almost all previous researchers set 4mm air bubble diameter at INLET of bubble column. Here, We are using PBM too. For CFDPBM coupling we have 10 classes of different size distributions. We applied EuEu two phase models. Any guidances would be highly appreciated to tell how to set 4mm air bubble dia at INLET ? Regards How to set 4mm Initial Diameter of air bubble in Ansys Fluent ?  ResearchGate. Available from: https://www.researchgate.net/post/Ho...n_Ansys_Fluent [accessed Apr 6, 2016]. 

April 6, 2016, 04:32 

#45  
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April 6, 2016, 04:57 

#46  
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Error is : Divergence detected in AMG solver: bin2fraction Divergence detected in AMG solver: bin3fraction Divergence detected in AMG solver: bin4fraction Divergence detected in AMG solver: bin5fraction Divergence detected in AMG solver: bin6fraction Divergence detected in AMG solver: bin7fraction Divergence detected in AMG solver: bin8fraction Divergence detected in AMG solver: bin9fraction Divergence detected in AMG solver: bin2fraction Divergence detected in AMG solver: bin3fraction Divergence detected in AMG solver: bin4fraction Divergence detected in AMG solver: bin5fraction Divergence detected in AMG solver: bin6fraction Divergence detected in AMG solver: bin7fraction Divergence detected in AMG solver: bin8fraction Divergence detected in AMG solver: bin9fraction Divergence detected in AMG solver: bin2fraction Divergence detected in AMG solver: bin3fraction Divergence detected in AMG solver: bin4fraction Divergence detected in AMG solver: bin5fraction Divergence detected in AMG solver: bin6fraction Divergence detected in AMG solver: bin7fraction Divergence detected in AMG solver: bin8fraction Divergence detected in AMG solver: bin9fraction turbulent viscosity limited to viscosity ratio of 1.000000e+05 in 10690 cells Error at Node 0: floating point exception Error at Node 2: floating point exception 

April 6, 2016, 05:02 

#47  
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April 6, 2016, 05:04 

#48 
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April 6, 2016, 05:17 

#49 
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There could be several reasons for Divergence.
1. Check all BCs 2. Check initial condition 3. Check time step 4. Lean down the model. for e.g. do not activate nucleation, growth, agg, coalescence etc. just run the case from inlet conditions. Finally u should see no change in bubble size but 4 mm is spread in your domain based on flow. you can also reduce the classes to 5 may be first. no to turbulence. no to any complex process. just check the flow. 4. Step by step activate each phenomena 5. Check solver settings URF etc... it is important to run the model step by step and go forward to complete the model. 

April 6, 2016, 05:27 

#50  
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May 29, 2016, 06:18 

#51 
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rahgoshafan
Join Date: Jul 2009
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Hello All
I need simulation PBM in vessel mixture but i don't define PBM please help me with example file 

May 30, 2016, 02:02 

#52 
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May 30, 2016, 09:10 
hi every body

#53 
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fati
Join Date: May 2016
Posts: 3
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in my simulation, I should calculated the electric field intensity and so computing aggregation rate with writing udf in pbm model, becouse the electric field causes agregation. can I compute the electric field intensity with mhd model? and in writing udf,I do not need to calculate the field through the writing udf?
thanks 

May 31, 2016, 11:36 

#54 
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fati
Join Date: May 2016
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hi friends
I'm elementry in writing udf. can anyone help me to writing udf for aggregation rate, couse the electric field with AC flow in population balance model ? the equations for Ac field are available. thank Last edited by fatia; June 1, 2016 at 06:27. 

June 2, 2016, 09:44 

#55 
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rahgoshafan
Join Date: Jul 2009
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Hi furqanrk
I need help for define udf code for any model i need see sample file in fluent. i read any time PBM manual but don't learn how make pbm model 

June 3, 2016, 11:45 

#56 
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June 21, 2016, 13:50 

#57 
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rahgoshafan
Join Date: Jul 2009
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Hi All
I need tutorial for step of config and solve Population Balance Model . Thanks for help email is: rahgoshafan@yahoo.com 

July 18, 2016, 12:18 

#58 
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n kh
Join Date: Jan 2013
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hi every one i am trying to use pbm in fluent, and my fluent version is not licensed unfortunately.... how can i enable pbm in my fluent? thanks 

July 19, 2016, 08:18 

#59  
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The population balance module is loaded into ANSYS Fluent through the text user interface (TUI). The module can only be loaded when a valid ANSYS Fluent case file has been set or read. The text command to load the module is: define → models → addonmodule A list of ANSYS Fluent addon modules is displayed: > /define/models/addonmodule Fluent Addon Modules: 0. None 1. MHD Model 2. Fiber Model 3. Fuel Cell and Electrolysis Model 4. SOFC Model with Unresolved Electrolyte 5. Population Balance Model 6. Adjoint Solver 7. SinglePotential Battery Model 8. DualPotential MSMD Battery Model Enter Module Number: [0] 5 Select the Population Balance Model by entering the module number 5. During the loading process a scheme library containing the graphical and text user interface, and a UDF library containing a set of user defined functions are loaded into ANSYS Fluent. A message Addon Module: popbal...loaded! is displayed at the end of the loading process. Best of Luck 

July 19, 2016, 08:39 

#60  
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adnan
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Quote:
#include "udf.h" #include "dpm.h" #define ZERO 0.0000001 DEFINE_DPM_DRAG(dpm_gidaspow_drag,Re,p) { Thread *thread_g, *thread_s, *mix_thread; real x_vel_g, x_vel_s, y_vel_g, y_vel_s, abs_v, slip_x, slip_y, rho_g, rho_s, mu_g, dp, reyp, reyp1,void_g, void_s, cd, D; cell_t cell; real left_term; real dragcoefficient; /*find the cell index and thread of the cell that the particle is currently in*/ cell=P_CELL_THREAD(p); mix_thread=THREAD_SUB_THREAD(P_CELL_THREAD(p),0); /* find the threads for the gas (primary) */ thread_g = THREAD_SUB_THREAD(mix_thread,0);/* gas phase thread */ thread_s = THREAD_SUB_THREAD(mix_thread,1);/* solid phase thread */ /* find phase velocities and properties*/ x_vel_g = C_U(cell, thread_g); y_vel_g = C_V(cell, thread_g); x_vel_s=P_VEL(p)[0]; y_vel_s=P_VEL(p)[1]; slip_x = x_vel_g  x_vel_s; slip_y = y_vel_g  y_vel_s; rho_g = C_R(cell, thread_g); /*density*/ rho_s =P_RHO(p); mu_g = C_MU_L(cell, thread_g); /*laminar viscosity*/ dp =P_DIAM(p); /*compute slip*/ abs_v = sqrt(slip_x*slip_x + slip_y*slip_y); /*absolute value of slip velocity*/ void_g = C_VOF(cell, thread_g);/* gas vol frac*/ Message ("Voidage of gas phase %f \n", void_g); void_s = 1void_g;/*particle vol frac*/ /*compute reynolds number*/ reyp =rho_g*abs_v*dp/mu_g; /*no volume fraction???*/ reyp1 = void_g*reyp; if(reyp1<1000) cd=24/reyp1*(1+0.15*pow(reyp1,0.687)); else cd = 0.44; if (void_g <=0.8) { /* Ergun Drag Model */ D = 150.0*void_s*void_s*mu_g/void_g/dp/dp+1.75*void_s*rho_g*abs_v/dp; } else { /* Wen & Yu Model */ D = 0.75*cd*void_g*void_s*rho_g*abs_v/dp/pow(void_g,2.65); } left_term=rho_s*pow(dp,2)/mu_g; dragcoefficient=left_term*D/(abs_v+ZERO); return dragcoefficient; } 

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