While working with rotating components, stability analysis is critical, as instability can lead to catastrophic failure. Rotating systems can lead to unstable responses due to asymmetrical inertia of the disk, asymmetrical stiffness of the shaft, or cross-coupling effects due to bearings. From the designer’s point of view, it’s important to ensure that the potentially unstable modes lie outside the operating range of the machine. Let’s explore how to predict the instability in rotor systems using the COMSOL Multiphysics® software.

Guest blogger Bojan Jokanović of SGL Carbon GmbH, one of the world’s leading manufacturers of carbon-based products, discusses the optimization of thermal processes in the carbon industry. Carbon products are used in many industries, including semiconductors, car manufacturing, ceramics, and metallurgy. Properties of graphite including high-temperature stability, good thermal and electric conducting behavior, and high chemical stability make this material unique. However, carbon manufacturing is an energy-intensive industry. We must build digital process chains to optimize processes and minimize costs.

In a previous blog post, we discussed the paraxial Gaussian beam formula. Today, we’ll talk about a more accurate formulation for Gaussian beams, available as of version 5.3a of the COMSOL® software. This formulation based on a plane wave expansion can handle nonparaxial Gaussian beams more accurately than the conventional paraxial formulation.

We have already discussed the factors that make a high-quality mesh and how to prepare a CFD model geometry for meshing. In this follow-up blog post, learn about physics-controlled meshing, adaptive mesh refinement, and how to use a variety of meshing tools in the COMSOL Multiphysics® software for your fluid flow simulations.

The quality of a computational fluid dynamics (CFD) model is often determined by the quality of the mesh used to solve the problem. A good mesh facilitates convergence, reduces memory requirements, and results in accurate solutions. It is therefore worthwhile to invest time and thought into creating the mesh when solving a CFD problem. In this blog post, we describe the factors of a quality mesh and how to prepare a fluid flow model geometry for meshing.

Following up on a previous blog post about glacier flow modeling, we are going to delve a bit further into a crucial component of geophysics modeling in general: parameterizing numerical models using observations. Let’s see how we can quantify sensitivity and infer unknown parameters through indirect observations using the COMSOL Multiphysics® software and add-on Optimization Module.

Say you want to compute thermal expansion and stresses in an object. You provide the heat fluxes and temperature constraints on the boundaries, compute, and get a convergence error. Often, this result comes from a lack of displacement constraints. However, it is not trivial to provide constraints that do not induce artificial stresses. Today, we showcase the Rigid Motion Suppression feature in the COMSOL Multiphysics® software, which you can use to automatically figure out the constraints you need.

A thorough analysis of a loudspeaker driver is not limited to a frequency-domain study. Some desirable and undesirable (but nonetheless exciting) effects can only be caught by a nonlinear time-domain study. Here, we will discuss how system nonlinearities affect the generated sound and how to use the COMSOL Multiphysics® software to perform a nonlinear distortion analysis of a loudspeaker driver.

In a previous blog post, we explained how to run a job from the COMSOL Multiphysics® software on clusters directly from the COMSOL Desktop® environment, without any interaction with a Linux® operating system terminal. Since this terminal is sometimes treated with excessive respect, the ability to start a cluster job directly from the graphical user interface is one of the most useful features in the COMSOL® software. Plus, there’s more to it… Enter the Cluster Sweep node.

If you want to create an animation from your simulation results, the COMSOL Multiphysics® software offers a variety of powerful and flexible options. In this blog post, we will explore the idea of creating a nontrivial animation by combining slices along the azimuthal direction for a 3D model.