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Meet our aerodynamics specialist

Written by Vostermans Ventilation | Nov 5, 2021 10:29:42 AM

After studying for 5 years, Robin wanted nothing more than to put his knowledge into practice. An open application in 2013 turned out to be the golden ticket to our Research & Development (R&D) department. But why is someone with a University Aerospace Engineering background working for a fan manufacturer?

"The University course consisted of several parts. Although aerospace does have something magical about it, I soon found that my interest was triggered by the complexity of helicopter rotors and experimental aerodynamics. While its a very theoretical field, it is precisely the connection with practice that I find interesting. It’s therefore not at all surprising that I am now putting my knowledge into practice at a fan manufacturer; validating theoretical calculations in our own wind tunnel, and performing measurements myself on a test site in a greenhouse.

My first project was to get the current V-FloFan working. A number of engineers had come up with a fan that had to move air in a completely new way. The airflow would be blown down through a dome and then sucked back into the fan. However, they couldn't get the airflow to go around. It took us a year to get the product working properly. Then you feel quite proud when you see that these fans are appreciated by customers all over the world. A competitor recently tried to copy the product. Of course, we tested the performance of the copied product in our R&D department. I must confess that I did slightly enjoy seeing that they did not manage to get the airflow to go around nicely.

Aerodynamics is often undervalued. After all, you cannot see with the naked eye how good an impeller is. A counterfeit product may look almost the same as an original Multifan fan, and just like a fan at home, air comes out of that too. However, it doesn’t say anything about the efficiency and effectiveness of the product, while in the agricultural sector that can be essential. I once visited a customer who was experience issues with noise. I found that air was being sucked into the fan at an angle because of a disturbance in airflow. The fan was therefore loaded unevenly, which caused a disturbing noise. Such a small environmental factor can make the customer think that the product is not working properly, while it is usually environmental factors that cause these kinds of issues.

Developing a new impeller is time-consuming and complex. On top of that, the perfect impeller does not exist. In fact, the shape of the blade depends on the fan application. For example, in an environment where there is no backpressure, it is best to use an impeller with slender blades, while in an area with a lot of pressure, a wide blade is more effective. Then you still have to take into account noise, power, and air volume. A complex puzzle akin to developing an F1 car.  

What is interesting nowadays, is that you can quickly have a prototype 3D printed and then tested in our own automatic wind tunnel. This allows you to validate the theoretical calculations in practice directly. Finally, we measure each impeller using an impeller measurement tool. By measuring the length, width, straightness and wrongness, we determine whether the impeller actually turned out the way we imagined it. In recent years, we have invested a great deal in this in order to raise our complete range of impellers to a higher level.

Where will we be in 10 years? I think aerodynamics will become increasingly important. After all, its a means of making our fans more energy efficient without having to work with sensitive electronics, something that is often avoided in the agricultural sector. Additionally, I believe that in recent years we have laid the foundation to make more improvements in this area in the near future. Although it is of course still important that our customer cleans the fan every now and then, otherwise I may have done my work for nothing."