Heat Transfer Blog Posts

Predicting Microwave Drying of Potatoes
You may not think of reheating food in the microwave as a drying process, but as we saw at the COMSOL Conference 2013 Boston, microwave technology — the same technology used in domestic microwave ovens — can be used for drying fruits and vegetables. One poster presented at the conference featured microwave drying of potatoes and how the heat and mass transfer that occurs can be modeled to predict the drying process.

Thermal Modeling of Surfaces with Wavelength-Dependent Emissivity
Whenever we are solving a thermal problem where radiation is significant, we need to know the emissivities of all of our surfaces. Emissivity is a measure of the ability of a surface to emit energy by radiation, and it can depend strongly upon the wavelength of the radiation. This is very relevant for thermal problems where the temperature variation is large or when there is exposure to a high-temperature source of radiation such as the sun. In this post on […]

Coupling Transport and Solid Mechanics Models for Better Puffed Rice
In my work at COMSOL, it’s always interesting to see how broad the field of heat transfer can be. Far from being limited to steel ingots and CPU fans, researchers often use COMSOL Multiphysics to study heat transfer in food manufacturing. One good example of this is the study of thermal and mechanical effects in the production of puffed rice, which was presented at the COMSOL Conference 2013 in Boston.

Mersen Simulates Joule Heating in Busbars and Fuses
Joule heating is a fairly standard type of simulation for COMSOL users nowadays. It involves solving for electrical voltage and temperature fields simultaneously with highly temperature-dependent material properties. Controlling Joule heating is very important when designing and manufacturing electrical systems components. The electric protection group at manufacturing company Mersen France used to base their busbar and fuse designs on trial-and-error, but these days they turn to COMSOL Multiphysics.

Exploring the Leidenfrost Effect
The Leidenfrost effect, also known as film boiling, occurs when a liquid comes into contact with a solid that is at a temperature well above the liquid’s boiling point. Upon contact, a layer of vapor forms between the liquid-solid interface, creating a barrier between the two. There are many examples of this phenomenon, ranging from something you may have seen in your kitchen (water “dancing” around in a pan) to things you shouldn’t try at home (dipping your hand into […]

The Advantages of Mechatronic Simulation at KOSTAL
For 60 years, the technology manufacturer KOSTAL Group has been implementing various electrical systems in cars, making your driving experience more enjoyable. For instance, the Automotive Electrical Systems division of KOSTAL placed indicator switches near the steering wheel and created integrated-function push buttons. Over the years, their patents and designs have become more complex and revolutionary. Currently, they are working on optimizing the design of their roof modules for premium cars using mechatronic simulation.

MEMS Energy Harvester for Reusing Waste Heat
Today we welcome another guest post from Kyle Koppenhoefer of AltaSim Technologies, a COMSOL Certified Consultant. In this entry he will discuss modeling MEMS energy harvesting devices. During our recent webinar with COMSOL on thermal-structure interaction modeling, we at AltaSim Technologies demonstrated modeling of a MEMS energy harvester that scavenges waste heat. Examples of sources for waste heat range from microprocessor chips, to internal combustion engines, to chemical processing plants. If the waste heat generated from these cases could be […]

How to Model a Shell and Tube Heat Exchanger
Shell and tube heat exchangers are one of the most widely used type of heat exchanger in the processing industries (65% of the market according to H. S. Lee’s book, Thermal Design) and are commonly found in oil refineries, nuclear power plants, and other large-scale chemical processes. Additionally, they can be found in many engines and are used to cool hydraulic fluid and oil. There are a variety of different configurations for these heat exchangers, but their basic concept can […]