Flow dependence on coordinate system?
I am working on modeling fluid structure interaction, and I have found that the flow changes whenever I move my model to a different location on the coordinate system. I literally selected everything...
View ArticleLift and Drag coefficients - 2D stationary turbulent k-epsilon flow
Hello, I am starting with COMSOL, and I have made a 2D flow simulation around a multi-element airfoil for a project at school. I used a turbulent k-epsilon flow for my model. After reading multiple...
View Articleheat exchanger
Hi Im trying to model a heat exchanger under Conjugate Heat Transfer module but i got an error. I attached the file. Would you please look at it and let me know where is my problem? Regards
View ArticleVelocity gradient expression in 2D-axisymmetric
Hello, the velocity gradient tensor for a 2D-axisymmetric problem presents, for the phiphi component, the following expression chns.graduDGphiphi = if(abs(r)<0.0010*h,d(u,r),u/r) does anyone know...
View ArticleMultiple-size particle tracing
Hello everyone I have a short question on the particle tracing module. Does anyone know that whether it is possible to simulat particles of different sizes in the same model. How to implement this...
View ArticleSurface evaporation, condensation
Hi, I want to model surface evaporation from a water flow at 40 Celsius and observe the consequent condensation on a cold surface. Can you help me with the model that I should use? I could not find...
View ArticleHow to set initial velocity in level-set method two phase flow for one phase
Hi guys, I am trying to set the initial velocity for a droplet as fluid 1, how can I set an initial velocity for the bulk of fluid (for example the the continuous phase or the drop) in level set...
View Articleparticle deformation througn a contrained channel
Hi there, I am doing COMSOL simulation to see the behavior of a particle flow through a microchannel. There is a area of the channel where particle size is greater than the cross section. So the...
View ArticleRunning FSI examples, "undefined value found"
Hi!, i am trying to run an fluid-structure example with use of the MEMS module, byt anytime i get the error "undefined value found..." for the variable mod1.v_solid. So i even downloaded the 2d fsi...
View ArticleError with the laminar flow inlet in plasma simulations
Hello! Using the laminar flow for plasma processes I have had some errors when the section of the inlet is small. I am trying to simulate a chamber where the inlet section has a radius of 0.0025 m, so...
View ArticleHow can I find the flow velocity of a specific coordinate point
Dear all, I would like to ask how can I find the flow velocity of a specific point (x=105, y=2.5) in my channel (it is shown in the picture). In the graph, if I click at any random point I got 3...
View ArticleConvergence behaviour in a stationary solver
Dear Comsol gurus, I have been dealing with a CFD/transport of diluted species (TDS) simulation for a while and I was hoping you could bring some light to the subject. I am simulating a flow in a micro...
View ArticleFluid flow channel in cantilever beam
Hello, My model is the following: a cantilever beam has one longitudinal channel containing a fluid flow. My goal is to find the effects of the fluid flow (viscosity, velocity, size of the channel) on...
View ArticleHow to find temperature variation for a single element in my model
My model has 7 elements as a whole. I am able to plot the temperature variations of the whole model but not for any separate element in the model. I request if somebody helps me know how to plot the...
View Articleold model cannot be reconstructed....
I am attempting to build on a model using Darcy's law to model solute transport under saturated conditions. The original model was built in COMSOL 3.5a, and I get an error message "Old model cannot be...
View ArticlePeristaltic Pump Model
Veryst's peristaltic pump model is practically identical to what I need to create (designing a muffin batter pump and would really like to model it)! Unfortunately I'm a student so I can't just hire...
View ArticleSessile droplet
I want to put a sessile droplet inside a channel. How to create a droplet of a specific material ? and how do I choose the model ? As a reference I was wondering about the model in one the Paper - A...
View ArticleAssigning material properties to an interior volume
I want to assign the empty volume within a closed container to be a fluid and assign material propertied to this fluid. I imported a closed 3D model that is made up of a number of solid parts contained...
View ArticleDifficulties with #985 Peristaltic Pump Model
Hi All (bear with me; I'm new) Working my way through the peristaltic pump tutorial and all has been a-okay thus far but once I get to the plot of the total volume (bottom of pg. 14) when I try to...
View ArticlePossible to export the streamline coordinates?
Hi, I am only using the laminar flow conditions, I have plotted the streamline after the simulation, is there anyway to get the streamline coordinate from the simulation? I like to export it if it is...
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