What is Sliding/Moving Mesh?
When a time-accurate solution for rotor-stator interaction (rather than a time-averaged solution) is desired, you must use the sliding mesh model to compute the unsteady flow field. The sliding mesh model is the most accurate method for simulating flows in multiple moving reference frames and is the most computationally demanding. As was mentioned, the sliding mesh model is theoretically the most accurate method for simulating rotating flows, and it can correctly describe the whole transient startup. However, it is also the most computationally demanding. This technique, applied to the specific case, results in two cell zones created separately. Each cell zone is bounded by an interface that meets the opposing cell zone. The two cell zones will slide relative to one another along the mesh interface in discrete steps. The AMI (arbitrary mesh interface) operates by projecting one patch’s geometry onto the other. In other words, the two sub-domains are geometrically separated but numerically connected by the AMI, ensuring that the values of a generic field are the same on both sides of the interface. The external cell is a simple steady partition in which the mesh does not move during the calculations. Instead, the internal partition, the cylindrical one, is a cell zone that rotates during the simulations. After each step, the internal mesh is rotated at a prescribed angle. The advantage of this technique is that it ensures the best accuracy avoiding, at the same time, mesh deformation.
ANSYS Fluent has various modules for modeling and simulating the moving objects (moving reference frame, moving mesh, dynamic mesh, moving wall). Each module has its limitation, advantage, and disadvantage, and in most problems, only one and a special module can correctly model the system of interest. For example, we can model HAWTs by both MRF and moving mesh modules, and the result of both modules would be the same. However, due to the high computational time of the moving-mesh module, it’s more economical to use the MRF module, and we prefer to model HAWT by the MRF method. But for VAWT, it is impossible to model it with the MRF model because the wind turbine blade situation VS wind direction will change over time. Therefore, VAWTs must be simulated using a moving mesh module.
To expand your knowledge about this method and its application in the industry and academic fields, you can enter the Moving Mesh tab by clicking on the link to find more projects. For instance, the following simulation models a Twing Screw Pump using this method.
MR-CFD, an Expert in the Field of Sliding/Moving Mesh Simulations
With several years of experience simulating a wide range of problems in various CFD fields using ANSYS Fluent software, the MR-CFD team is ready to offer extensive modeling, meshing, and simulation services. Simulation Services for Moving/sliding mesh are categorized as follows:
- Various types of horizontal and vertical axis wind turbine
- Various types and situations of Tidal turbines (two and three and four-bladed)
- Simulation of turbomachinery includes (pumps, compressors, etc.)
- Airplane propeller CFD simulation
- Simulation turbofan and AFT fan
- Simulation of cavitation in Francis, Kaplan, and Pelton turbine
- Simulation of the rescue helicopter
You may find the related products in the categories mentioned above in our CFD shop by clicking on the following link:
Our services are not limited to the mentioned subjects, and the MR-CFD team is ready to undertake different and challenging projects ordered by our customers. You can consult with our experts freely and without charge and order your project by sending the problem details to us using the following address.
By outsourcing your project to the MR-CFD as a CFD simulation freelancer, you will not only receive the related project’s files (Geometry, Mesh, …), but also you will be provided with an extensive tutorial video demonstrating how you can create the geometry, mesh, and define the needed settings(pre-processing, processing and post-processing) in the ANSYS Fluent software all by yourself. Additionally, post-technical support is available to clarify issues and ambiguities.