## Understand Phenomena in the Viscous Catenary Problem via Simulation

##### Bridget Cunningham March 22, 2017

The viscous catenary problem has generated a lot of theoretical and experimental interest in recent years. This is due to the industrial importance of the rich phenomena that occur within it. Using the flexibility of the COMSOL Multiphysics® software, we can gain fundamental insights into complex problems like the viscous catenary problem and determine the validity of the assumptions made in previous analyses.

### Comparing Hydrodynamic Bearings with Rotordynamics Analyses

##### Bridget Cunningham March 1, 2017

To provide sufficient support for a rotating shaft or journal, it is important to choose a hydrodynamic bearing design with the right load capacity. If the applied loads are greater than a bearing design can handle, it can cause excessive wear and instability. With the Rotordynamics Module, an add-on product to the COMSOL Multiphysics® software, you can compare the load capacities for different types of hydrodynamic bearings and determine which one is best suited for your particular application.

### How to Analyze Beam Sections Using the Beam Section Calculator

##### Rémi Magnard February 28, 2017

When modeling a structure with beam elements, we don’t use the actual 3D geometry. Instead, we use a line model, which represents the other two dimensions through defining a set of cross-section properties. With the Beam Section Calculator simulation app, we can easily find the properties for a wide range of beam sections from European and American standards. The app also makes it simple to accurately compute the stress distribution for a given set of applied moments and forces.

### Perform Rotordynamic Analyses of a Reciprocating Engine’s Crankshaft

##### Bridget Cunningham January 2, 2017

When a reciprocating engine’s crankshaft is under rotation, self-excited vibrations occur. These vibrations result from the eccentricity of the crank pin and balance masses on the mechanical part. Here, we’ll accurately study the response of the rotors and the orbits of the mass balances on the shaft with the Rotordynamics Module, a new add-on product to the COMSOL Multiphysics® software and Structural Mechanics Module. From these results, you can improve a crankshaft’s design to reduce vibrations, while optimizing engine performance.

### Simulation Delivers Reliable Results for Piezoresistive Pressure Sensors

##### Bridget Cunningham December 26, 2016

Designing MEMS devices, such as piezoresistive pressure sensors, comes with challenges. For instance, accurately describing the operation of these devices requires the integration of various physics. With the COMSOL Multiphysics® software, you can easily couple multiphysics simulations in order to test a device’s performance and generate reliable results. Today, we’ll look at one example that showcases such capabilities.

### Can a Stiffness Be Negative?

##### Henrik Sönnerlind December 5, 2016

In finite element modeling, you may encounter formulations where a force does not monotonically increase with displacement. You can see this property in many material models that include degradation of the material. Such behavior is represented by a negative stiffness. In this blog post, we discuss some examples of negative stiffness, including the physical backgrounds and numerical implications. These ideas are not confined to mechanical analysis, even though the term stiffness originates in that field.

### Identify a Cricket Bat’s Sweet Spots with Structural Mechanics Analysis

##### Caty Fairclough November 11, 2016

In the highly competitive world of professional cricket, every swing is important. To deliver powerful shots, a batsman needs a well-designed bat and knowledge of how to best use it. One way to improve a player’s batting skills, and perhaps design better bats, is to locate their so-called “sweet spots”. A research team from the University of the West Indies achieved this by performing a structural analysis with the COMSOL Multiphysics® software.

### How to Reuse a Deformed Shape as a Geometry Input

##### Temesgen Kindo September 1, 2016

Suppose you take a piece of metal — a thin sheet, for example — and apply some mechanical loads. The metal will deform and take on a new shape that differs from the original undeformed configuration. Say you now want to use this deformed object as part of a new geometry construction. You can then solve another physics problem on the new composite domain. Today, we’ll demonstrate how to use a deformed object as an input to a geometry sequence.

### How to Model Adhesion and Decohesion in COMSOL Multiphysics

##### Henrik Sönnerlind July 28, 2016

In the latest version of COMSOL Multiphysics® — version 5.2a — we bring you new features designed to enhance your structural mechanics contact modeling. You can, for instance, simulate objects that stick together once they come in contact (adhesion) as well as those that pull apart (decohesion), including full cohesive-zone modeling. Learn how to address each of these scenarios using the new functionality in COMSOL Multiphysics.

### Evaluating an Insulin Micropump Design for Treating Diabetes

##### Bridget Cunningham July 21, 2016

In any form of treatment, it is always desirable to minimize the level of discomfort that the treatment process causes patients, while ensuring overall safety and effectiveness. For diabetes patients, insulin injections remain an important form of treatment, but the process itself can be painful. With the help of multiphysics simulation, a team of researchers from the University of Ontario Institute of Technology sought to develop a MEMS-based micropump that could administer insulin injections in a safe and painless way.

### GTI Streamlines Gas Pipeline Maintenance Procedures with Simulation

##### Brianne Costa July 11, 2016

For gas pipeline maintenance standards, the adage “rules are meant to be broken” may not apply, but “rules are meant to be updated” certainly does. Specifically, the generous distance requirements between pipeline squeeze-off locations and pipe fittings cause potentially unnecessary digging. This prompted Operations Technology Development (OTD), a partnership of natural gas distribution companies, to initiate a project with Gas Technology Institute (GTI), where researchers used simulation to investigate the standard distance requirements for streamlined and safe pipeline maintenance.