Turbomachines are devices within which the conversion of the total energy of a working medium into mechanical energy and vice versa. Turbomachines are generally divided into two main categories. The first category is used primarily to produce power. It includes, among others, steam turbines, gas turbines, and hydraulic turbines. The primary function of the second category is to increase the total pressure of the working fluid by consuming power. It includes compressors, pumps, and fans. Pumps and turbines have many different types due to their applications; however, the most popular ones in the industry are axial and centrifugal. Optimizing turbomachines is very important in the industry as they consume a lot of energy. Therefore, better performance reduces energy consumption and will finally help us have a cleaner environment.
How to Improve Turbomachines using CFD simulations?
The basic theory behind the Turbomachinery modeling process can be explained through the transmission of the kinetic energy of the fluid flow to the turbomachine itself or vice versa. In the two categories mentioned earlier, for turbomachines like turbines, a flow having a specific pressure and momentum hits the blades of the mentioned turbine, therefore transmitting its energy to the turbine, causing its shaft to rotate inside a generator and produce various forms of energy such as electricity. However, in machines like pumps and compressors, electricity is needed to rotate such devices’ impellers to transmit power to fluid for secondary targets.
Creating more effective turbo devices necessitates a deeper comprehension of the performance-influencing elements and their fine-tuning. Today’s computer-aided simulations make it simpler and more affordable than ever to offer solutions for optimizing the design and performance of Turbomachinery.
CAE engineers can easily optimize the design (blade geometry, flow angles, mass flow rate, and pressure drop) to increase the performance starting from the early stage of the design with the use of specific information on the flow pattern inside compressor’s turbines, pumps, and blowers.
In order to propose alternatives and effective design concepts, simulation-driven design for Turbomachinery aids in identifying the critical aspects affecting the device performance. The number of prototype testing is drastically decreased, but the number of virtual prototypes is limitless when using virtual computational fluid dynamics simulations. By reducing the number of measurements, CFD enables engineers working on Turbomachinery to develop new products more quickly.
CFD on Simulation of Radial Blowers
A blower is a specific tool used to blow high-pressure air, which typically has uses like dust-cleaning etc. A blower, for instance, is used to clean computer hardware and components. With its rotational motion, the device’s center motor generates significant air pressure, which is then directed out of the outlet portion of the device. Centrifugal blowers were used in the creation of this modeling. The centrifugal blower may take in air from its center, and this airflow then enters the impellers, which are in the shape of fin discs located in the center. The airflow rotates as a result of the blades’ rapid circular action.
The air pressure rises due to the centrifugal force, which also accelerates the airflow. Finally, a duct on the blower’s outer body directs this high-pressure air to the outside environment.
Early on in the design process, CFD can analyze several CAD models, decrease the need for physical prototypes and costly testing, and optimize the design for maximum performance.
CFD usage for the Vertical Axis Wind Turbine(VAWT)
Small wind turbines and urban wind energy are two study fields that frequently cross over. According to their axis of rotation, wind turbines in the wind industry can be divided into two categories: horizontal axis wind turbines and vertical axis wind turbines. Large-scale testing has shown the horizontal axis wind turbine design to be mature, effective, and economical; however, it is wind direction-dependent. Additionally, a yaw mechanism is required. A small HAWT performs poorly in the constructed environment due to the flow inclinations. In this regard, the VAWT idea has several benefits in an urban environment.
Cavitation inside the Turbomachines using CFD
Cavitation has been a key issue for pump system engineers for the past fifty years. Cavitation is the process whereby vapor bubbles develop in low-pressure areas of a flow. This occurrence typically occurs when the pressure within the pump’s flow route falls below the vapor pressure, which is the pressure that a vapor exerts when it is in thermodynamic equilibrium with its liquid at a given temperature. This typically occurs when there is insufficient pressure at the pump’s suction.
In regions where the pressure drops below the vapor pressure corresponding to that fluid temperature, cavitation appears as the production of gas bubbles. Pressure builds up as the liquid flows toward the pump’s exit, forcing the bubbles to implode and produce powerful shock waves that erode the metal surfaces, producing vibration and mechanical damage.
It still remains one of the most difficult subjects for CFD engineers to study, and it happens in various industries, including pumps, torpedoes, hydrofoils, and marine propellers.
This post just looked at a few CFD applications that can help improve Turbomachinery. The Mechanical business has many CFD applications, ranging from Pelton Wheel Turbine to modeling a 3-Blade Horizontal Axis Wind Turbine and Cavitation in a Radial Flow Pump to assess the main parameters such as velocity, temperature, and pressure, all of which are key challenges in the industry.
Most aspects of the Turbomachinery industry rely on fluid dynamics. Although physical prototypes are required for later phases of development, CFD studies may significantly speed up design and optimization in the early stages.
The MR-CFD team conducted numerous outsourcing simulation projects for industrial and researched Turbomachinery applications. With several years of experience simulating various problems in various CFD fields using ANSYS Fluent software, the MR-CFD team is ready to offer extensive services of simulation configurations. For example, Pelton Wheel Turbine simulation is freelanced and carried out to achieve the solution’s key parameters.
The Pelton turbine is the only impact hydraulic turbine currently in use. According to Newton’s second law, this turbine uses a fluid jet to generate energy. This turbine is hit by a pressurized water nozzle tangentially to the bucket connected to the runner and rotates the runner. The buckets are pairs so that the momentum is transferred smoothly and efficiently in addition to the balance of force that is applied. The pellets are in different sizes. Large sizes are used in dams because these turbines are specifically designed for large heads, and small sizes are used to generate electricity in remote areas.
ANSYS Fluent software simulates a small Pelton turbine with a diameter of 300 mm and 15 buckets in this project. Also, this project aims to get the amount of torque produced in this turbine.
The following research deals with the airflow on the HAWT blades, so the problem’s purpose is to study the distribution of velocity and pressure on the surface of the blades and their body. There are three areas around the blades for airflow. There is An area around the blades, an area in the front of the blades, and an area behind the blades. The airflow behaves normally in the front and behind the blades, while the rotational motion causes the rotational flow in the area around the blades.
The cavitation phenomenon occurs when the pressure of a liquid falls below its vapor pressure at a constant temperature. In this case, the particles turn from liquid to vapor, forming a bubble. This process is called cavitation. Now, if these bubbles are transferred to the high-pressure parts of the pump, they will collapse. This collapse of the bubble creates a vacuum locally, as a result of which the liquid particles around the bubble move towards the empty space at a very high speed and pressure.
The present problem simulates the cavitation phenomenon inside a radial flow pump using ANSYS Fluent software. This pump is of the centrifugal pump (radial flow) type; In this way, the desired fluid enters it parallel to the central axis and exits it radially or perpendicular to the inlet path. These types of pumps are commonly used to create high pressures at low flow rates and are also the most common type among pumps.
MR-CFD, an Expert in the Field of Turbomachinery Simulations
With several years of experience in simulating various problems in different CFD fields using ANSYS Fluent software, the MR-CFD Company is ready to offer extensive modeling, meshing, and simulation services. Our simulation Services for Turbomachinery simulations are categorized as follows:
- Simulation of different types of Turbines (HAWT, VAWT, Kaplan, Liam, etc.)
- Acoustic analysis and noise reduction of turbomachinery devices
- Investigation of the effect of cavitation inside the turbomachines
- Simulation of different types of pumps and compressors
- Simulation of multi-stage compressors
- Simulation radial blowers
- Simulation cross-flow blowers
- Wind farms Simulation
You may find the related products to the Turbomachinery simulation category in Training Shop.
Our services are not limited to the mentioned subjects, and the MR-CFD is ready to undertake different and challenging projects in the Turbomachinery Engineering modeling field ordered by our customers. We even accept carrying out CFD simulation for any abstract or concept design you have in your mind to turn them into reality and even help you reach the best design for what you may have imagined. You can benefit from MR-CFD expert consultation for free and then order your project to be simulated and trained.
By outsourcing your project to the MR-CFD as a CFD simulation freelancer, you will not only receive the related project’s resource files (Geometry, Mesh, Case & Data, …), 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.