Quantcast
Channel: Latest Discussions - COMSOL Forums
Browsing all 26512 articles
Browse latest View live

modeling sessile droplet evaporation

Dear Firends, does any one has experience with modeling phase change from liquid to gas ? is there exists any tutorial ? I intended to model evaporation of single droplet pinned of relatively hot...

View Article


Animation Scale Factor

I'm trying to create an animation of my simulation. Every time I create it (under Report > Animation), the scale factor is reactivated to some arbitrary value EVEN if I deselect it or specifically...

View Article


Heat transfer simulation result is much larger than experimental result

I modelled the heat transfer through a hollow brick to calculate the equivalent thermal conductivity. So general heat transfer and weakly compressible Navier-Stokes modules were taken to build the...

View Article

Some comments on pA material absolute pressure and CFD gauge & reference...

For those interested in pressure definitions As I read often comments on the Forum, and I heard many questions on the last workshop at the Milan conference on CFD pressure, gauge, absolute, reference...

View Article

Magnetic field

Does anybody know how to write this expression on comsol ( ∇/B/^2 )? I meant expression that replace "the gradient of the magnetic field norm square". Thank you

View Article


Local Edge System

Hello, I'm trying to implement a "Predescribed Displacement" Condition on an Edge using the local Edge Coordinate system. But i have the Problem that i couldn't find a reference to the "Local Edge...

View Article

2D Power Density

Good Afternoon, I am having some trouble calculating what my power density should be in my 2-D model. I am modeling a cross sectional cut of a heated aluminum plate in air. In my experimental runs, the...

View Article

How to write Nabla function in comsol 3.4

Hello, Can anyone tell me how to write nabla function in comsol 3.4? What is the syntax for this function? I wanna use it for dielectrophoresis and there is a term where I need to find the gradient of...

View Article


Defining a Piecewise function of two variables

Hello, I am trying to model NMR diffusion in COMSOL 4.3 and need to define a function beta at three different time intervals as follows: beta = gyro*(g*x) (0 < t < 0.016s) beta = 0 (0.016s < t...

View Article


How to generate a "Join Data" set from parametric steps?

How to generate a "Join Data" set from two stationary and parametric steps? Hello everybody. Does anyone know how to merge two solutions when one of them is the continuation of the other? For instance,...

View Article

Simulation of the magnetic fied

Hi, I have one physical NdFeB magnet and I need to simulate this magnet in Comsol 4.2a, but I dont know exactly how to do it. I know these parameters of the magnet: Remanence Br = 1380 mT Coercivity...

View Article

Please help me find how to achieve this function.

It seems to be a simple problem but I can't figure out how to make it. Description: a 2d transient model of a square is built, the left, bottom, and right side is thermal insulation and the top side is...

View Article

Line maximum: tabulating data

I need to take a series of line maximums (for Temperature, say) from a regular array of parallel lines which are perpendicular to the y-z plane and pass through a bounding box in 3D space. The line...

View Article


Maxwell stress tensor integration

Hi everyone! I'm still trying to compare the electrostatic force calculated by the expression (F=0.5*epsilon*V^2*A/g^2) with the result coming by Maxwell stress tensor in COMSOL. I used the suggestion...

View Article

Please help! (error: Undefined value found)

Hello everyone, I’m working on the following model from Comsol library: Batteries and fuel cells>>ht_pem. When I change the geometry to a more complex one, for example using two or three...

View Article


Eigen-frequency analysis of metal grating

Dear all, For a metal grating (see attached Structure_Reference.jpg), now I would like to analysis the dispersion relationship of surface plasmon wave supported by a metal grating, which propagates...

View Article

Mie Scattering problem, Csmcol 4.2a

Dear Fellows, I want to find module about "Mie Scattering", but I can not access to this module.www.comsol.com/showroom/gallery/3459/ Is that module still exist in the gallery or not? Thank you for...

View Article


Heat Transfer in Soils

Hi, I am a comsol user and I want to have a 2d axisymmetric model. In my model, I have a soil sample that I put a steel bar in the soil. I want to heat the steel bar with a constant temperature 500(k)...

View Article

How to change equation during a transient solution in V4.3

Hello everybody, I am simulating a transient solution by using transport of dilute species. I would like to change the equation during a transient solution and use the initial value of simulation 2...

View Article

Thermal Conductivity as a function of temperature

Hi all, I am trying to include thermal conductivity as a function of temperature in my model but its giving me error 'inconsistent unit'..let us say the function is -1.27E-9*(T)^3+8.09E-6*(T)^2-...

View Article
Browsing all 26512 articles
Browse latest View live