## How to Integrate Functions Without Knowing the Limits of the Integral

##### Walter Frei April 30, 2014

We all know that COMSOL Multiphysics can take partial derivatives. After all, it solves partial differential equations via the finite element method. Did you know that you can also solve integrals? That alone shouldn’t be very surprising, since solving finite element problems requires that you integrate functions. The COMSOL software architecture allows you to do a bit more than just evaluate an integral; you can also solve problems where you don’t know the limits of the integral! Here’s how.

Read More##### Bettina Schieche April 29, 2014

If you use finite element simulation software, such as COMSOL Multiphysics, you will come across the expression “weak form” at some point. When you do, you may wonder what this expression means. Weak form is actually a very powerful concept. Here, you will learn about its basic ideas and corresponding benefits.

Read More##### Mark Fowler April 28, 2014

A recent discovery indicates that certain particles can be drawn into crystalline structures through the controlled use of ultraviolet light and chemistry. This discovery can eventually lead to the possibility of creating color-changing surfaces and materials for reasons of dynamic camouflaging.

Read More##### Mark Fowler April 25, 2014

Born 140 years ago today, Guglielmo Marconi was a Nobel Prize-winning electrical engineer and an Italian inventor who is best known for pioneering long-distance radio transmission and the commercial success of radio.

Read More##### Phillip Oberdorfer April 24, 2014

In the second part of our Geothermal Energy series, we focus on the coupled heat transport and subsurface flow processes that determine the thermal development of the subsurface due to geothermal heat production. The described processes are demonstrated in an example model of a hydrothermal doublet system.

Read More##### Alexandra Foley April 23, 2014

Magnetic fields are fundamental forces in the universe. Without them, planetary orbits, electricity, and elementary particles could not exist. Helmholtz coils are used by scientists to generate uniform magnetic fields to study electromagnetism and its characteristics. They are used in MRI, spectroscopy, magnetoresistance measurements, and equipment calibrations. Here, we’ll look at what Helmholtz coils are, why they are important, and how can they be modeled.

Read More##### Guest Nagi Elabbasi April 22, 2014

Today, we invite guest blogger Nagi Elabbasi of Veryst Engineering to share a modeling example of immersed beams. When thin structures such as beams, plates, or shells are immersed in a fluid, their natural frequencies are reduced. The fluid also affects their mode shapes and is a source of damping. This phenomenon affects structures across a wide range of industries and sizes, from micro-scale structures (e.g. MEMS actuators) to larger structures (e.g. ships).

Read More##### Clemens Ruhl April 21, 2014

The Wall Distance interface is used to calculate the distance to a wall in the turbulent flow interfaces available in COMSOL Multiphysics. It can be combined with any other interface and comes in handy when we need to calculate the distance to the nearest wall or detect, as part of a dynamic model, when a moving object will hit a wall. Today, we will study how the Wall Distance interface works and how other interfaces can benefit from its capabilities.

Read More##### Fanny Littmarck April 18, 2014

Did you know that you can use MATLAB® functions in your COMSOL Multiphysics® models? Well, you can, and in this video tutorial we will show you how, using LiveLink™ for MATLAB®.

Read More##### Edmund Dickinson April 17, 2014

What’s a penny made of? Though they appear to be solid copper coins, they actually don’t contain much copper at all these days. Instead, the U.S. Mint saves money by applying only a veneer of valuable metal onto a less expensive one. Have you ever thought about the manufacturing process by which this is achieved? Let’s find out.

Read More##### Lorant Olasz April 16, 2014

The geometric kernel is the software component responsible for handling geometry in COMSOL Multiphysics®. You may be wondering what this means or how and why you would use it when modeling. Let’s find out.

Read More