A major challenge faced by pump and fan designers is to predict the performance across a range of operating conditions. Prototype-benchmark testing is a technique that has been used for many years in the industry, but is time consuming and expensive. Many companies have discovered the benefits of Virtual prototyping, and have leveraged CAE tools to reduce costs and time to market. Autodesk Simulation CFD contains many powerful tools for simulating the performance of fans and pumps, and users have found that they can improve their design system through their use.
There are two primary classifications of turbomachines:
These devices are different from positive displacement pumps and gear pumps. The flow rate is closely related to the rotational speed, and depends on a pressure differential instead of a displacement volume. A turbomachine must be rotating to maintain a pressure difference, whereas a positive displacement pump maintains a pressure difference due to fluid trapped in its internal passages. Use the Linear and Angular Motion capabilities to simulate devices such as positive displacement pumps and gear pumps.
Examples of common turbomachines include:
The techniques presented in this topic focus primarily on centrifugal pumps, axial fans, and hydraulic turbines. These have been developed by Blue Ridge Numerics Engineers and applied to a large number of different machines. While these work for most applications, there are situations in which some customization may be required.
Note also that these techniques are fairly conservative, and in some cases it may be possible to achieve convergence quicker than the recommended techniques. As experience is developed with a specific application, feel free to optimize these techniques to achieve results using the most efficient process possible.