Pipe Flow Module
New App: Geothermal Heat Pump
Geothermal heating is an environmentally friendly and energy-efficient method to supply modern and well insulated houses with heat. Heat exchangers placed at a sufficient depth in the ground below the house utilize subsurface heat, where temperatures are almost constant throughout the year.
The Geothermal Heat Pump design app studies different pipe configurations of a ground heat exchanger. It provides information on the performance of ground-coupled heat exchangers for different specifications (depth, pattern, pipes configuration, and heating conditions); temperature conditions; soil thermal conductivity; and temperature gradient.
The heater can also be turned off if the daily heat demand is achieved, and then turned on again after 24 hours. The temperature at the pipe’s outlet can be controlled and compared to the minimum temperature required in the heat exchanger specifications.
Temperature field computed by the Geothermal Heat Pump app from the operating settings defined by the user.
New App: Organ Pipe Design
The Organ Pipe Designer allows you to study the design of an organ pipe, and then play the sound and pitch of the changed design in a user-friendly app. The pipe sound includes the effects of different harmonics with different amplitudes.
The organ pipe is modeled using the Pipe Acoustics, Frequency Domain interface in COMSOL Multiphysics. The simulation app allows you to analyze how the first fundamental resonance frequency varies with the pipe radius and wall thickness, as well as with the ambient pressure and temperature.
Using the app, you can find the full frequency response, including the fundamental frequency and the harmonics. With a Java® code written method, the app will detect the location and amplitude of all harmonics in the response, thus extending the analysis beyond the built-in functionality of the COMSOL Multiphysics user interface.
User interface for the Organ Pipe Design app, showing the SPL response.
Improved Pipe Flow Interface
The Pipe Flow interface has been amended with an inertial term. This means that gradually diverging or converging pipe sections properly account for a pressure change due to the velocity change (Bernoulli effect). Also, sudden expansions and contractions properly account for the Bernoulli effect. The updated stabilization and element shape functions now allow compressible flows for Ma < 0.3. Models created in previous versions of COMSOL Multiphysics open using the old interface with a notification. For new models, only the new interface is available in the physics interface list.