# mass flow in is not equal to mass flow out

 Register Blogs Members List Search Today's Posts Mark Forums Read September 17, 2009, 10:08 mass flow in is not equal to mass flow out #1 New Member   anonymous Join Date: Sep 2009 Posts: 2 Rep Power: 0 Can anyone pls help me with this problem. My problem is mass flow in is not equal to mass flow out. thank you This is my model http://img183.imageshack.us/i/48217966.png/ This is my CCL infor: Code: ```# State file created: 2009/09/14 15:18:14 # CFX-12.0.1 build 2009.04.14-23.02 LIBRARY: CEL: EXPRESSIONS: DenH = (DenWater - DenRef) DenRef = 1.185 [kg m^-3] DenWater = 997 [kg m^-3] DownH = 0.68 [m] DownPres = DenH*g*DownVFWater*(DownH-y) DownVFAir = step((y-DownH)/1[m]) DownVFWater = 1-DownVFAir UpH = 0.78 [m] UpPres = DenH*g*UpVFWater*(UpH-y) UpVFAir = step((y-UpH)/1[m]) UpVFWater = 1-UpVFAir END END MATERIAL GROUP: Air Data Group Description = Ideal gas and constant property air. Constant \ properties are for dry air at STP (0 C, 1 atm) and 25 C, 1 atm. END MATERIAL GROUP: CHT Solids Group Description = Pure solid substances that can be used for conjugate \ heat transfer. END MATERIAL GROUP: Calorically Perfect Ideal Gases Group Description = Ideal gases with constant specific heat capacity. \ Specific heat is evaluated at STP. END MATERIAL GROUP: Constant Property Gases Group Description = Gaseous substances with constant properties. \ Properties are calculated at STP (0C and 1 atm). Can be combined with \ NASA SP-273 materials for combustion modelling. END MATERIAL GROUP: Constant Property Liquids Group Description = Liquid substances with constant properties. END MATERIAL GROUP: Dry Peng Robinson Group Description = Materials with properties specified using the built \ in Peng Robinson equation of state. Suitable for dry real gas modelling. END MATERIAL GROUP: Dry Redlich Kwong Group Description = Materials with properties specified using the built \ in Redlich Kwong equation of state. Suitable for dry real gas modelling. END MATERIAL GROUP: Dry Steam Group Description = Materials with properties specified using the IAPWS \ equation of state. Suitable for dry steam modelling. END MATERIAL GROUP: Gas Phase Combustion Group Description = Ideal gas materials which can be use for gas phase \ combustion. Ideal gas specific heat coefficients are specified using \ the NASA SP-273 format. END MATERIAL GROUP: IAPWS IF97 Group Description = Liquid, vapour and binary mixture materials which use \ the IAPWS IF-97 equation of state. Materials are suitable for \ compressible liquids, phase change calculations and dry steam flows. END MATERIAL GROUP: Interphase Mass Transfer Group Description = Materials with reference properties suitable for \ performing either Eulerian or Lagrangian multiphase mass transfer \ problems. Examples include cavitation, evaporation or condensation. END MATERIAL GROUP: Liquid Phase Combustion Group Description = Liquid and homogenous binary mixture materials which \ can be included with Gas Phase Combustion materials if combustion \ modelling also requires phase change (eg: evaporation) for certain \ components. END MATERIAL GROUP: Particle Solids Group Description = Pure solid substances that can be used for particle \ tracking END MATERIAL GROUP: Peng Robinson Dry Hydrocarbons Group Description = Common hydrocarbons which use the Peng Robinson \ equation of state. Suitable for dry real gas models. END MATERIAL GROUP: Peng Robinson Dry Refrigerants Group Description = Common refrigerants which use the Peng Robinson \ equation of state. Suitable for dry real gas models. END MATERIAL GROUP: Peng Robinson Dry Steam Group Description = Water materials which use the Peng Robinson equation \ of state. Suitable for dry steam modelling. END MATERIAL GROUP: Peng Robinson Wet Hydrocarbons Group Description = Common hydrocarbons which use the Peng Robinson \ equation of state. Suitable for condensing real gas models. END MATERIAL GROUP: Peng Robinson Wet Refrigerants Group Description = Common refrigerants which use the Peng Robinson \ equation of state. Suitable for condensing real gas models. END MATERIAL GROUP: Peng Robinson Wet Steam Group Description = Water materials which use the Peng Robinson equation \ of state. Suitable for condensing steam modelling. END MATERIAL GROUP: Real Gas Combustion Group Description = Real gas materials which can be use for gas phase \ combustion. Ideal gas specific heat coefficients are specified using \ the NASA SP-273 format. END MATERIAL GROUP: Redlich Kwong Dry Hydrocarbons Group Description = Common hydrocarbons which use the Redlich Kwong \ equation of state. Suitable for dry real gas models. END MATERIAL GROUP: Redlich Kwong Dry Refrigerants Group Description = Common refrigerants which use the Redlich Kwong \ equation of state. Suitable for dry real gas models. END MATERIAL GROUP: Redlich Kwong Dry Steam Group Description = Water materials which use the Redlich Kwong equation \ of state. Suitable for dry steam modelling. END MATERIAL GROUP: Redlich Kwong Wet Hydrocarbons Group Description = Common hydrocarbons which use the Redlich Kwong \ equation of state. Suitable for condensing real gas models. END MATERIAL GROUP: Redlich Kwong Wet Refrigerants Group Description = Common refrigerants which use the Redlich Kwong \ equation of state. Suitable for condensing real gas models. END MATERIAL GROUP: Redlich Kwong Wet Steam Group Description = Water materials which use the Redlich Kwong equation \ of state. Suitable for condensing steam modelling. END MATERIAL GROUP: Soot Group Description = Solid substances that can be used when performing \ soot modelling END MATERIAL GROUP: User Group Description = Materials that are defined by the user END MATERIAL GROUP: Water Data Group Description = Liquid and vapour water materials with constant \ properties. Can be combined with NASA SP-273 materials for combustion \ modelling. END MATERIAL GROUP: Wet Peng Robinson Group Description = Materials with properties specified using the built \ in Peng Robinson equation of state. Suitable for wet real gas modelling. END MATERIAL GROUP: Wet Redlich Kwong Group Description = Materials with properties specified using the built \ in Redlich Kwong equation of state. Suitable for wet real gas modelling. END MATERIAL GROUP: Wet Steam Group Description = Materials with properties specified using the IAPWS \ equation of state. Suitable for wet steam modelling. END MATERIAL: Air Ideal Gas Material Description = Air Ideal Gas (constant Cp) Material Group = Air Data, Calorically Perfect Ideal Gases Option = Pure Substance Thermodynamic State = Gas PROPERTIES: Option = General Material EQUATION OF STATE: Molar Mass = 28.96 [kg kmol^-1] Option = Ideal Gas END SPECIFIC HEAT CAPACITY: Option = Value Specific Heat Capacity = 1.0044E+03 [J kg^-1 K^-1] Specific Heat Type = Constant Pressure END REFERENCE STATE: Option = Specified Point Reference Pressure = 1 [atm] Reference Specific Enthalpy = 0. [J/kg] Reference Specific Entropy = 0. [J/kg/K] Reference Temperature = 25 [C] END DYNAMIC VISCOSITY: Dynamic Viscosity = 1.831E-05 [kg m^-1 s^-1] Option = Value END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 2.61E-2 [W m^-1 K^-1] END ABSORPTION COEFFICIENT: Absorption Coefficient = 0.01 [m^-1] Option = Value END SCATTERING COEFFICIENT: Option = Value Scattering Coefficient = 0.0 [m^-1] END REFRACTIVE INDEX: Option = Value Refractive Index = 1.0 [m m^-1] END END END MATERIAL: Air at 25 C Material Description = Air at 25 C and 1 atm (dry) Material Group = Air Data, Constant Property Gases Option = Pure Substance Thermodynamic State = Gas PROPERTIES: Option = General Material EQUATION OF STATE: Density = 1.185 [kg m^-3] Molar Mass = 28.96 [kg kmol^-1] Option = Value END SPECIFIC HEAT CAPACITY: Option = Value Specific Heat Capacity = 1.0044E+03 [J kg^-1 K^-1] Specific Heat Type = Constant Pressure END REFERENCE STATE: Option = Specified Point Reference Pressure = 1 [atm] Reference Specific Enthalpy = 0. [J/kg] Reference Specific Entropy = 0. [J/kg/K] Reference Temperature = 25 [C] END DYNAMIC VISCOSITY: Dynamic Viscosity = 1.831E-05 [kg m^-1 s^-1] Option = Value END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 2.61E-02 [W m^-1 K^-1] END ABSORPTION COEFFICIENT: Absorption Coefficient = 0.01 [m^-1] Option = Value END SCATTERING COEFFICIENT: Option = Value Scattering Coefficient = 0.0 [m^-1] END REFRACTIVE INDEX: Option = Value Refractive Index = 1.0 [m m^-1] END THERMAL EXPANSIVITY: Option = Value Thermal Expansivity = 0.003356 [K^-1] END END END MATERIAL: Aluminium Material Group = CHT Solids, Particle Solids Option = Pure Substance Thermodynamic State = Solid PROPERTIES: Option = General Material EQUATION OF STATE: Density = 2702 [kg m^-3] Molar Mass = 26.98 [kg kmol^-1] Option = Value END SPECIFIC HEAT CAPACITY: Option = Value Specific Heat Capacity = 9.03E+02 [J kg^-1 K^-1] END REFERENCE STATE: Option = Specified Point Reference Specific Enthalpy = 0 [J/kg] Reference Specific Entropy = 0 [J/kg/K] Reference Temperature = 25 [C] END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 237 [W m^-1 K^-1] END END END MATERIAL: Copper Material Group = CHT Solids, Particle Solids Option = Pure Substance Thermodynamic State = Solid PROPERTIES: Option = General Material EQUATION OF STATE: Density = 8933 [kg m^-3] Molar Mass = 63.55 [kg kmol^-1] Option = Value END SPECIFIC HEAT CAPACITY: Option = Value Specific Heat Capacity = 3.85E+02 [J kg^-1 K^-1] END REFERENCE STATE: Option = Specified Point Reference Specific Enthalpy = 0 [J/kg] Reference Specific Entropy = 0 [J/kg/K] Reference Temperature = 25 [C] END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 401.0 [W m^-1 K^-1] END END END MATERIAL: Soot Material Group = Soot Option = Pure Substance Thermodynamic State = Solid PROPERTIES: Option = General Material EQUATION OF STATE: Density = 2000 [kg m^-3] Molar Mass = 12 [kg kmol^-1] Option = Value END REFERENCE STATE: Option = Automatic END ABSORPTION COEFFICIENT: Absorption Coefficient = 0 [m^-1] Option = Value END END END MATERIAL: Steel Material Group = CHT Solids, Particle Solids Option = Pure Substance Thermodynamic State = Solid PROPERTIES: Option = General Material EQUATION OF STATE: Density = 7854 [kg m^-3] Molar Mass = 55.85 [kg kmol^-1] Option = Value END SPECIFIC HEAT CAPACITY: Option = Value Specific Heat Capacity = 4.34E+02 [J kg^-1 K^-1] END REFERENCE STATE: Option = Specified Point Reference Specific Enthalpy = 0 [J/kg] Reference Specific Entropy = 0 [J/kg/K] Reference Temperature = 25 [C] END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 60.5 [W m^-1 K^-1] END END END MATERIAL: Water Material Description = Water (liquid) Material Group = Water Data, Constant Property Liquids Option = Pure Substance Thermodynamic State = Liquid PROPERTIES: Option = General Material EQUATION OF STATE: Density = 997.0 [kg m^-3] Molar Mass = 18.02 [kg kmol^-1] Option = Value END SPECIFIC HEAT CAPACITY: Option = Value Specific Heat Capacity = 4181.7 [J kg^-1 K^-1] Specific Heat Type = Constant Pressure END REFERENCE STATE: Option = Specified Point Reference Pressure = 1 [atm] Reference Specific Enthalpy = 0.0 [J/kg] Reference Specific Entropy = 0.0 [J/kg/K] Reference Temperature = 25 [C] END DYNAMIC VISCOSITY: Dynamic Viscosity = 8.899E-4 [kg m^-1 s^-1] Option = Value END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 0.6069 [W m^-1 K^-1] END ABSORPTION COEFFICIENT: Absorption Coefficient = 1.0 [m^-1] Option = Value END SCATTERING COEFFICIENT: Option = Value Scattering Coefficient = 0.0 [m^-1] END REFRACTIVE INDEX: Option = Value Refractive Index = 1.0 [m m^-1] END THERMAL EXPANSIVITY: Option = Value Thermal Expansivity = 2.57E-04 [K^-1] END END END MATERIAL: Water Ideal Gas Material Description = Water Vapour Ideal Gas (100 C and 1 atm) Material Group = Calorically Perfect Ideal Gases, Water Data Option = Pure Substance Thermodynamic State = Gas PROPERTIES: Option = General Material EQUATION OF STATE: Molar Mass = 18.02 [kg kmol^-1] Option = Ideal Gas END SPECIFIC HEAT CAPACITY: Option = Value Specific Heat Capacity = 2080.1 [J kg^-1 K^-1] Specific Heat Type = Constant Pressure END REFERENCE STATE: Option = Specified Point Reference Pressure = 1.014 [bar] Reference Specific Enthalpy = 0. [J/kg] Reference Specific Entropy = 0. [J/kg/K] Reference Temperature = 100 [C] END DYNAMIC VISCOSITY: Dynamic Viscosity = 9.4E-06 [kg m^-1 s^-1] Option = Value END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 193E-04 [W m^-1 K^-1] END ABSORPTION COEFFICIENT: Absorption Coefficient = 1.0 [m^-1] Option = Value END SCATTERING COEFFICIENT: Option = Value Scattering Coefficient = 0.0 [m^-1] END REFRACTIVE INDEX: Option = Value Refractive Index = 1.0 [m m^-1] END END END END FLOW: Flow Analysis 1 SOLUTION UNITS: Angle Units = [rad] Length Units = [m] Mass Units = [kg] Solid Angle Units = [sr] Temperature Units = [K] Time Units = [s] END ANALYSIS TYPE: Option = Steady State EXTERNAL SOLVER COUPLING: Option = None END END DOMAIN: Domain 1 Coord Frame = Coord 0 Domain Type = Fluid Location = Assembly BOUNDARY: Boundary 1 Boundary Type = INLET Location = F98.104 BOUNDARY CONDITIONS: FLOW DIRECTION: Option = Normal to Boundary Condition END FLOW REGIME: Option = Subsonic END MASS AND MOMENTUM: Mass Flow Rate = 3 [kg s^-1] Option = Bulk Mass Flow Rate END END FLUID: air BOUNDARY CONDITIONS: VOLUME FRACTION: Option = Value Volume Fraction = UpVFAir END END END FLUID: water BOUNDARY CONDITIONS: VOLUME FRACTION: Option = Value Volume Fraction = UpVFWater END END END END BOUNDARY: Boundary 2 Boundary Type = OPENING Location = F100.104 BOUNDARY CONDITIONS: FLOW DIRECTION: Option = Normal to Boundary Condition END FLOW REGIME: Option = Subsonic END MASS AND MOMENTUM: Option = Opening Pressure and Direction Relative Pressure = DownPres END END FLUID: air BOUNDARY CONDITIONS: VOLUME FRACTION: Option = Value Volume Fraction = 0 END END END FLUID: water BOUNDARY CONDITIONS: VOLUME FRACTION: Option = Value Volume Fraction = 1 END END END END BOUNDARY: Boundary 3 Boundary Type = OPENING Location = F105.104,F108.104 BOUNDARY CONDITIONS: FLOW DIRECTION: Option = Normal to Boundary Condition END FLOW REGIME: Option = Subsonic END MASS AND MOMENTUM: Option = Opening Pressure and Direction Relative Pressure = DownPres END END FLUID: air BOUNDARY CONDITIONS: VOLUME FRACTION: Option = Value Volume Fraction = 1 END END END FLUID: water BOUNDARY CONDITIONS: VOLUME FRACTION: Option = Value Volume Fraction = 0 END END END END BOUNDARY: Domain 1 Default Boundary Type = WALL Location = \ F101.104,F102.104,F103.104,F106.104,F107.104,F109.104,F110.104,F111.10\ 4,F112.104,F113.104,F114.104,F83.104,F84.104,F85.104,F86.104,F87.104,F\ 88.104,F89.104,F90.104,F91.104,F92.104,F93.104,F94.104,F95.104,F96.104\ ,F97.104,F99.104 BOUNDARY CONDITIONS: MASS AND MOMENTUM: Option = No Slip Wall END END END DOMAIN MODELS: BUOYANCY MODEL: Buoyancy Reference Density = 1.185 [kg m^-3] Gravity X Component = 0 [m s^-2] Gravity Y Component = -9.8 [m s^-2] Gravity Z Component = 0 [m s^-2] Option = Buoyant BUOYANCY REFERENCE LOCATION: Option = Automatic END END DOMAIN MOTION: Option = Stationary END MESH DEFORMATION: Option = None END REFERENCE PRESSURE: Reference Pressure = 1 [atm] END END FLUID DEFINITION: air Material = Air at 25 C Option = Material Library MORPHOLOGY: Option = Continuous Fluid END END FLUID DEFINITION: water Material = Water Option = Material Library MORPHOLOGY: Option = Continuous Fluid END END FLUID MODELS: COMBUSTION MODEL: Option = None END FLUID: air FLUID BUOYANCY MODEL: Option = Density Difference END END FLUID: water FLUID BUOYANCY MODEL: Option = Density Difference END END HEAT TRANSFER MODEL: Fluid Temperature = 25 [C] Homogeneous Model = Off Option = Isothermal END THERMAL RADIATION MODEL: Option = None END TURBULENCE MODEL: Option = Laminar END END FLUID PAIR: air | water INTERPHASE TRANSFER MODEL: Option = None END MASS TRANSFER: Option = None END SURFACE TENSION MODEL: Option = None END END INITIALISATION: Option = Automatic FLUID: air INITIAL CONDITIONS: VOLUME FRACTION: Option = Automatic with Value Volume Fraction = UpVFAir END END END FLUID: water INITIAL CONDITIONS: VOLUME FRACTION: Option = Automatic with Value Volume Fraction = UpVFWater END END END INITIAL CONDITIONS: Velocity Type = Cartesian CARTESIAN VELOCITY COMPONENTS: Option = Automatic with Value U = 0 [m s^-1] V = 0 [m s^-1] W = 0 [m s^-1] END STATIC PRESSURE: Option = Automatic with Value Relative Pressure = 0 [Pa] END END END MULTIPHASE MODELS: Homogeneous Model = On FREE SURFACE MODEL: Option = Standard END END END MESH ADAPTION: Activate Adaption = On Domain Name = Domain 1 Save Intermediate Files = On Subdomain List = Assembly ADAPTION ADVANCED OPTIONS: Node Allocation Parameter = -2 Number of Adaption Levels = 2 END ADAPTION CONVERGENCE CRITERIA: Adaption Target Residual = 0.001 Maximum Iterations per Step = 100 Option = RMS Norm for Residuals END ADAPTION CRITERIA: Maximum Number of Adaption Steps = 2 Node Factor = 4 Option = Multiple of Initial Mesh Variables List = air.Conservative Volume Fraction END ADAPTION METHOD: Minimum Edge Length = 0.0 Option = Solution Variation END END OUTPUT CONTROL: RESULTS: File Compression Level = Default Option = Standard END END SOLVER CONTROL: ADVECTION SCHEME: Option = High Resolution END CONVERGENCE CONTROL: Length Scale Option = Conservative Maximum Number of Iterations = 100 Minimum Number of Iterations = 1 Timescale Control = Auto Timescale Timescale Factor = 1.0 END CONVERGENCE CRITERIA: Residual Target = 1.E-4 Residual Type = RMS END DYNAMIC MODEL CONTROL: Global Dynamic Model Control = Yes END END END COMMAND FILE: Version = 12.0.1 END``` Last edited by wyldckat; September 3, 2015 at 17:09. Reason: Added [CODE][/CODE] markers and disabled embedded image   September 18, 2009, 08:22 #2 Super Moderator   Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,260 Rep Power: 136    Your simulation is not converged. Have you looked here: http://www.cfd-online.com/Wiki/Ansys...gence_criteria Also output some backup files as the simulation progresses. You can load them in CFD-Post and it may help you diagnose what is wrong.   September 18, 2009, 09:07 #3 New Member   anonymous Join Date: Sep 2009 Posts: 2 Rep Power: 0 thank you. which tutorial should i look through, if i want to add lio into the flow?   March 19, 2018, 01:06 #4 New Member   Dave Join Date: Mar 2018 Location: United States Posts: 14 Rep Power: 6 Hey, I am in a same boat right now. Just in case if you know, please let me know - where can I find the function TO FIND the mass flow rate in ANSYS Fluent? Secondly, I want to know whether the fluid flow is distributed equally or not to my two outlets from one inlet pipe. If you know how to find the fluid distribution (that function in ANSYS fluent), please let me know. Thanks!   March 19, 2018, 04:14 #5 Senior Member   Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,662 Rep Power: 25 I would suggest to use CFX. This gives many more options in monitoring, like changing range and adding monitors on the fly.. Also, it automatically saves your monitors in your res files, whereas Fluent doesn't. Very frustrating in my opinion. But if you want to use Fluent and get the values at the end of your run, just go to Results > Reports > Fluxes > MassFlowRate at your boundaries. If you want to monitor them during your run, go to Report definitions and create the samething there and make sure you create a monitor.   March 19, 2018, 05:16 #6
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Dave
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 Originally Posted by Gert-Jan I would suggest to use CFX. This gives many more options in monitoring, like changing range and adding monitors on the fly.. Also, it automatically saves your monitors in your res files, whereas Fluent doesn't. Very frustrating in my opinion. But if you want to use Fluent and get the values at the end of your run, just go to Results > Reports > Fluxes > MassFlowRate at your boundaries. If you want to monitor them during your run, go to Report definitions and create the samething there and make sure you create a monitor.
Hi Gert, Thank you for your swift reply. I will certainly try in CFX. To be honest, I am bit new with CFD and hence, I am learning. I followed your instruction and indeed it was helpful. I can at least find the mass flow rate now - i.e. under Solution in ANSYS Fluent. However, the result for Mass Flow Rate that I got for my model is; At Inlet: 1.006 Kg/s and at outlet 1: -0.4291 kg/s and at outlet 2; -0.5767 kg/s. It seems, in my case I can see Mas in = Mass out

Is this result sufficient enough to tell me that the fluid flow is not distributed equally at outlet 1 and outlet 2 from single inlet pipe? Can you please explain? Your response will be highly appreciated. Thank you!   March 19, 2018, 05:22 #7 Senior Member   Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,662 Rep Power: 25 Fluent says so, so you might believe it. But It depends on your case, the accuracy and validity of your setup, the convergence, etc. Impossible for me to say based on the input you provided.   March 19, 2018, 05:30 #8
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Dave
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 Hi Gert, Thank you for your swift reply. I will certainly try in CFX. To be honest, I am bit new with CFD and hence, I am learning. I followed your instruction and indeed it was helpful. I can at least find the mass flow rate now - i.e. under Solution in ANSYS Fluent. However, the result for Mass Flow Rate that I got for my model is; At Inlet: 1.006 Kg/s and at outlet 1: -0.4291 kg/s and at outlet 2; -0.5767 kg/s. It seems, in my case I can see Mas in = Mass out Is this result sufficient enough to tell me that the fluid flow is not distributed equally at outlet 1 and outlet 2 from single inlet pipe? Can you please explain? Your response will be highly appreciated. Thank you!
In addition to my above statement - I mean I wanted to say;

Mass Flow Rate (M.F.R.) Results can tell me that whether the fluid flow is distributed equally or not at Outlets 1 and 2?

Because my M.F.R. result for outlet 1 = -0.429 kg/s
outlet 2 = -0.5767 kg/s

Does this value tells me that my fluid is not distributed equally?   March 19, 2018, 05:37 #9
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Dave
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 Originally Posted by Gert-Jan Fluent says so, so you might believe it. But It depends on your case, the accuracy and validity of your setup, the convergence, etc. Impossible for me to say based on the input you provided.
Thank you Gert for your patience as I might sound silly. But like I said, I am a new learner.

Well, I do understand that it truly depends upon my Boundary Conditions, my convergence, and so on. I totally agree with you on that front.

But let's assume, that my BC, convergence, and other criteria are perfect. So, then Mass Flow Rate will be sufficient enough to tell me whether my flow is distributed equally or not? As I mentioned above, in my case, I found two different values at outlets 1 and 2. So, should I consider that the flow is not distributed equally?

Secondly, Mass flow rate is the only way in ANSYS Fluent which can tell me the fluid flow is distributed properly or not?

Thank you so much Gert!   March 19, 2018, 05:39 #10 Senior Member   Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,662 Rep Power: 25 Yes of course. It tells you that it is not equally distributed. D.R likes this.   March 19, 2018, 06:00 #11 New Member   Dave Join Date: Mar 2018 Location: United States Posts: 14 Rep Power: 6 Thank you Gert, I have been breaking my head for whole day to find this. Watched many tutorials but couldn't find what I have been looking for. You save my time. One last question, with respect to the same enquiry! In order to find fluid distribution (i.e. equal or non-equal) in two or more pipes from one single pipe, I have set up my boundary condition which is as below: At Inlet, Velocity = 26 m/s At outlet 1, Outflow = 1 At outlet 2, outflow = 1 (flow rate weighing) So, I believe if I will keep outflow same, i.e outflow =1 for both outlets, then ANSYS Fluent will only figure out for the values at Outlet 1 and 2. (Likewise we keep pressure value = 0 at Outlet and then ANSYS Fluent tells us the pressure distribution throughout the body including at outlet - same concept I was thinking here to keep outflow = 1 for both. So, ANSYS will tell me whether my flow is going to be equal at outlets or not?) Please correct me if I am wrong! Just in case if you know, please let me know on this. Thank you so much!   March 19, 2018, 06:12 #12 Senior Member   Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,662 Rep Power: 25 Remember, this is CFX Forum, not the Fluent Forum. I know only a bit of Fluent. I don't know what "Outflow = 1" means. But it looks like a fraction to me. So I would use 0.5 for both outlets. Not? I always use pressure outlets or massflow outlets. If you use 2 massflow outlets you can also distribute the flow easily if you set the 1.006kg/s at your inlet.   March 19, 2018, 06:21 #13
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Dave
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 Originally Posted by Gert-Jan Remember, this is CFX Forum, not the Fluent Forum. I know only a bit of Fluent. I don't know what "Outflow = 1" means. But it looks like a fraction to me. So I would use 0.5 for both outlets. Not? I always use pressure outlets or massflow outlets. If you use 2 massflow outlets you can also distribute the flow easily if you set the 1.006kg/s at your inlet.
Oops I did not know that I am on a different platform and asking something else. Although you answered me for my enquiry, so, I truly appreciate you for your support mate. I am working on my Uni project and I am close to my deadline. Your information indeed saved my time. Thank you Gert!  Thread Tools Search this Thread Show Printable Version Email this Page Search this Thread: Advanced Search Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are Off Pingbacks are On Refbacks are On Forum Rules Similar Threads Thread Thread Starter Forum Replies Last Post andy P. Main CFD Forum 2 February 9, 2007 11:41 Masood FLUENT 0 May 22, 2005 01:32 michael FLUENT 4 February 21, 2005 04:48 Pravir Kumar Rai FLUENT 0 February 19, 2003 15:03 Pravir Kumar Rai FLUENT 0 February 17, 2003 20:23

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