Moving Reference Frame (MRF) – ANSYS Fluent Training Package, 10 Practical Exercises for BEGINNERS

Description

Moving Reference Frame (MRF) ANSYS Fluent CFD Simulation Training Package for BEGINNER Users

This training package includes 10 practical Moving Reference Frame (Frame Motion) exercises using ANSYS Fluent software. MR CFD suggests this package for BEGINNER users who tends to learn the simulation process of MRF problems without any strong background.

Wind Turbine

Project number 1 deals with the airflow on the HAWT blades, so the purpose of the problem is to study the distribution of velocity and pressure on the surface of the blades and their body. There is an area around the blades, in the front of the blades, and behind the blades. The airflow behaves normally in the front and behind the blades, while in the area around the blades, the rotational motion of the blades causes the rotational flow.

Project number 2 will simulate an airflow field close to a standard horizontal axis wind turbine. The geometry included a rotary zone for the turbine walls and a stationary zone for the rest of the domain. The inlet is considered to wind with 1 m/s, and the turbine zone rotates with 16 RPM. This study aims to investigate the behavior of airflow and pressure distribution and study drag force.

Project number 3 studies an incompressible isothermal airflow close to a standard horizontal axis wind turbine considering turbine BASE, modeled in three dimensions. The geometry is a wind turbine with a 30-meter base inside a 300-meter wind tunnel. Also, we select the maximum speed of 1 m/s is for the wind and the turbine velocity of 30 RPM.

Recently, an entirely new small-scale wind turbine design named Liam-F1 Urban Wind Turbine can operate at approximately 80% of the Betz Limit, or 47.4% overall efficiency, which states the theoretical maximum efficiency of any wind turbine is only 59.3%. Project number 4 will simulate an airflow field adjacent to Liam F1 wind turbine. The geometry included a rotary zone for the turbine walls and a stationary zone for the rest of the domain. The inlet is considered 3 m/s, and the turbine zone rotates with 300 RPM.

Compressor (Moving Reference Frame)

Project number 5 is to simulate a centrifugal compressor with a diffuser. This Compressor uses positive pressure while using centrifugal force to compress the gas. With the compressor impellers’ rotation, low-pressure air is sucked from the central axis, and its pressure increases the cause of the diffuser in the air path, leaving each blade is an increase in air pressure. When the fluid exits the central part of the Compressor, it has kinetic energy and potential. Since the amount of pressure changes in the passing fluid is inversely related to the square of the fluid velocity (according to the Bernoulli relation), it should be tried to reduce the compressor blades’ output velocity to increase the amount of outlet fluid pressure.

Project number 6 simulates the airflow inside a four-row Multistage Compressor. The Compressor designed in this simulation is of axial type and consists of four rows, including two rows of stator and two rows of the rotor. In general, Axial Flow Compressors are compressors whose airflow is parallel to the axis of rotation. Axial compressors consist of two main parts: the rotor and the stator. The Compressor consists of a series of rows with airfoil cross-sections called rotor and stator.

Blower

Project number 7 simulates a Centrifugal Blower. The blower is a device for blowing high-pressure air, which generally has applications such as dust cleaning. The rotational motion of the blades at high speed causes the airflow to rotate. The centrifugal force increases the air pressure and, consequently, the airflow’s velocity. Finally, this high-pressure air is directed to the outside environment through a duct installed on the blower’s outer body.

Rotating Cylinder

Project number 8 will simulate airflow in a rectangular channel. A dimpled cylindrical object is placed in the channel. The airflow enters the rectangular channel at a horizontal velocity of 0.45 m / s, colliding with the cylindrical body. The cylindrical body rotates at an angular velocity of 20 radians per second (rad/s) around the central axis; thus, the Moving Wall must be defined. Therefore, the fluid simulation area is divided into two parts, which include the rotating area (having a cylinder with a constant angular velocity) and the area of the fluid (the inner space of the rectangular channel other than the cylinder).

Project number 9 simulates the heat transfer and cooling of a wall from a model with a semi-cylinder shape. The model rotates around a particular axis (model z-axis) at a speed equivalent to 400 rpm. Therefore, to define this rotational motion in the model, the Frame Motion technique with a rotational speed of 400 rpm has been used. The exterior sectional wall of the model under constant heat flux is equal to 1000 W.m-2, and on the outer surface of this sectional wall, there are five ducts for airflow.

Fan (Moving Reference Frame)

In Project number 10, steady airflow is investigated between two 3-bladed series Fans that rotate at an angular velocity of 300 rpm. Rotation of fans generates air suction at the inlet boundary with a flow rate equal to 2.95755 m3/s. The air velocity reaches values up to 25 m/s on the domain centerline; however, maximum air velocity in the domain is equivalent to 47.05 m/s, which is captured downstream of the first fan.

You can obtain Geometry & Mesh file and a comprehensive Training Movie that presents how to solve the problem and extract all desired results.