COMSOL: Simulation of liquid nitrogen cooling (Help please)

In summary, a 10x10x0.5 mm InSb sample is attached to a cooled copper table with silver glue, while liquid nitrogen passes through the table. The sample is exposed to a beam of electrons, causing the surface to heat up at a temperature of 300 K and a pressure of 1 bar. The COMSOL modules used for simulations include heat transfer in solids, laminar flow, and multyphysics. However, it is not possible to calculate the heating during cooling. A nitrogen dynamic viscosity of 161,4 E-6 (Pa*s) is also mentioned. The conversation then moves on to simulations of heating with COMSOL, specifically for LN2, and it seems that the simulation was
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Engineer_Kosyakova
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TL;DR Summary
Simulation of electron beam heating (SEM) of an InSb sample with nitrogen cooling. It is not possible to calculate the heating during cooling in COMSOL. Maybe I'm using the wrong modules for cooling? Without cooling, the heating counts correctly.
The InSb sample (parameters 10x10x0.5 mm) is glued with silver glue to a cooled copper table. Liquid nitrogen passes through the table. While the model is at a temperature of 300 K and at a normal pressure of 1 bar. The sample is affected by a beam of electrons, which causes the surface to heat up. Modules used in COMSOL:
1. Heat transfer in Solids
2. Laminar Flow
3. Multyphysics (auto)
It is not possible to calculate the heating during cooling. Nitrogen Dynamic Viscosity - 161,4 E-6 (Pa*s)
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Good afternoon! Yes, it seems that everything turned out on a more powerful computer.
 

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FAQ: COMSOL: Simulation of liquid nitrogen cooling (Help please)

What are the key steps to set up a liquid nitrogen cooling simulation in COMSOL?

To set up a liquid nitrogen cooling simulation in COMSOL, you need to follow these key steps: 1. Define the geometry of your model.2. Select the appropriate physics interfaces, such as Heat Transfer in Solids and Fluid Flow.3. Specify the material properties, including those of liquid nitrogen.4. Set up boundary conditions, including cooling surfaces and initial temperatures.5. Mesh the geometry appropriately.6. Run the simulation and analyze the results.

How do I define the material properties for liquid nitrogen in COMSOL?

To define the material properties for liquid nitrogen in COMSOL, you need to enter the relevant thermophysical properties such as density, specific heat capacity, thermal conductivity, and viscosity. These can be input manually based on literature values or imported from a material library if available. Ensure that the properties are temperature-dependent if necessary.

What boundary conditions should I use for liquid nitrogen cooling simulations?

For liquid nitrogen cooling simulations, typical boundary conditions include specifying a convective heat flux or a heat transfer coefficient on surfaces in contact with the liquid nitrogen. You may also need to set inlet and outlet conditions for fluid flow if modeling the movement of liquid nitrogen. Initial temperature conditions for the materials being cooled should also be defined.

How can I ensure accurate meshing for my liquid nitrogen cooling model?

Accurate meshing is crucial for reliable simulation results. Use a finer mesh in regions with high temperature gradients or complex geometries. Adaptive meshing can also be beneficial. It’s often helpful to start with a coarser mesh to get preliminary results and then refine the mesh based on those results to ensure accuracy.

What post-processing steps are necessary to analyze the results of my simulation?

Post-processing steps include visualizing temperature distributions, fluid flow patterns, and heat fluxes. You can create plots and animations to observe cooling effects over time. Additionally, you may need to calculate derived values such as cooling rates or thermal stresses. COMSOL provides various tools for these analyses, including cut planes, isosurfaces, and probe points.

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