Modeling Aeroacoustics with the Linearized Navier-Stokes Equations

Mads Herring Jensen July 25, 2017

Detailed modeling of the complex interaction of flow and acoustics is achieved in the COMSOL Multiphysics® software and add-on Acoustics Module using the linearized Navier-Stokes interfaces. With the release of version 5.3, the capabilities were further extended with the addition of a new stabilization scheme. This allows robust simulations of systems with acoustic properties that are modified by or depend on a turbulent background flow; e.g., automotive exhaust systems. Here, we introduce important modeling concepts and present application examples.

Read More

Bridget Cunningham July 17, 2017

On the morning of March 22, 2006, NASA launched their Space Technology 5 mission. For about three months, miniaturized satellites explored Earth’s magnetic fields collecting high-quality measurements. Beyond gathering scientific data, the mission represents a turning point. Instead of large traditional satellite missions, miniaturized technology is taking precedence in space exploration. And within these systems, MEMS technology could serve as a means of active thermal control. Further improvements are already taking shape with the help of multiphysics simulation.

Read More

Prashant Srivastava July 12, 2017

Vibration in rotating machinery is very sensitive to the geometric, structural, and inertial properties of the various rotating and stationary components interacting with each other. These properties include the location of the mounted components and their inertial properties, bearing characteristics, and shaft properties. To understand the effects of these parameters, start with a simple model and perform various analyses to correlate the rotor response within the same model. Let’s demonstrate this process with a simply supported beam rotor example.

Read More

Bridget Cunningham July 10, 2017

Of the 72 million potential hearing aid users around the world, each needs a device fitted to meet their needs. In-the-ear measurements are performed to ensure both comfort and effectiveness. These measurements require the use of a microphone — the size of which can cause issues. The device can be too large to fit into the measured sound field. Alternatively, it can be too big compared to the wavelength and disturb the acoustic field. One solution is a probe tube…

Read More

Bridget Cunningham July 4, 2017

Many manufacturing processes already benefit from selective laser melting. The potential for combining this technique with high-melting materials is clear, but there are challenges to consider. For instance, these materials have a much narrower processing window. To better understand their behavior in selective laser melting, one research group built a model to analyze the thermal and fluid dynamics of laser beam-matter interaction. Their results generated further momentum in extending the use of this technique to process refractory metals.

Read More

Claire Bost June 14, 2017

When ambient air flows through porous media, it carries moisture. In this process, temperature and moisture are coupled: The vapor saturates depending on the temperature conditions, while latent heat effects due to evaporation and condensation modify the temperature. We discussed heat and moisture transport in air in a previous blog post. Let’s address the specific transport processes we need to consider in pores and how to model heat and moisture transport in porous media with the COMSOL Multiphysics® software.

Read More

Bridget Cunningham June 12, 2017

In the last seven years, the output of the manufacturing industry has increased by a total of around 10–20%. This growth is partly thanks to technologies and processes that save on time and costs, such as 3D printing and, as is described here, powder compaction. To model this process, we can use the new porous plasticity models in the latest version of the COMSOL Multiphysics® software.

Read More

Claire Bost June 9, 2017

Whenever ambient air is considered in an engineering context, temperature and moisture are intrinsically related. Vapor reaches a saturation point depending on the temperature and pressure conditions, while the action of latent heat modifies temperature distribution. These phenomena must be considered to optimize processes affected by phase changes, particularly when trying to prevent condensation occurring in devices. Let’s see how to model heat and moisture transport in air with the COMSOL Multiphysics® software.

Read More

Bridget Paulus June 8, 2017

Solar-grade silicon is becoming more popular for applications such as communications and photovoltaics. While it’s important to keep up with this growing demand, the current method of producing solar-grade silicon is energy intensive and expensive. To find a more efficient process, researchers at JPM Silicon GmbH explored a novel method using a microwave furnace. By simulating the internal processes, they aim to optimize their microwave furnace design to produce low-cost solar-grade silicon.

Read More

Bridget Cunningham May 30, 2017

Every year, over 40 million fire sprinkler systems are fitted worldwide. These systems are effective due to their piping designs, which are resistant to high heat and mechanical damage. A popular choice for such designs is threaded steel pipe. But analyzing a complex pipe design is challenging because of the detailed geometry. What approach can we take to efficiently combine accurate geometrical designs with reliable stress analyses? Version 5.3 of the COMSOL® software offers functionality for this purpose.

Read More

Prashant Srivastava May 25, 2017

Rotating components are important elements in machines such as gas turbines, turbochargers, pumps, compressors, electric generators, and motors. Designing such a component requires studying its critical speed, which is the speed at which the amplitude of the vibration in the system becomes large — often leading to failure. Let’s explore how to find the critical speeds for a wide range of rotors via the Rotor Bearing System Simulator, created using the COMSOL Multiphysics® software.

Read More


Categories


Tags

1 2 3 32