Determining RC EDF Motor Parameters

[Jdo300]

Hello All,

I am new to the field of electrical ducted fan (EDF) jets and am currently working on a new aerodynamic design using SolidWorks and Flow Simulation for aerodynamics testing. For my computer model, I can enter data for a fan that I would like to use for the thrust of my models, and my intent is to use one of the many, readily available RC EDF units available online.

However, the problem is that my model requires the fan data to be entered in terms of the volumetric flow rate and pressure differential created by the fan, but the only manufacturer data available for most RC fans is the thrust, max power, and maybe efficiency in some cases. I'm wondering if there may be any ways to estimate what the max volumetric flow rate and pressure difference could be knowing the max thrust of the ducted fan and the diameter of the fan itself?

NOTE: I am actually an electrical engineer by trade and am just getting more into the field of aerodynamics so please forgive my ignorance.

Thank you all for any advice/insights you can offer,

- Jason O

 

[Achy47]

Hello Jason,

Thank you for reaching out to the community for advice on your EDF jet project. As a scientist with experience in aerodynamics and fluid dynamics, I can offer some insights and suggestions for your situation.

Firstly, it is important to understand that the thrust, power, and efficiency data provided by manufacturers for RC EDF units are typically measured under ideal conditions and may not accurately represent the performance of the fan in your specific design. Therefore, it is necessary to estimate the volumetric flow rate and pressure differential based on the available data.

One approach you could take is to use the fan's thrust and efficiency to calculate the power input, and then use that power input along with the fan's diameter to estimate the maximum volumetric flow rate. This can be done using the equation for power (P) in terms of thrust (T) and velocity (V):

P = TV

Then, assuming the fan is operating at its maximum efficiency, you can use the power input to estimate the maximum velocity and, subsequently, the maximum volumetric flow rate.

As for estimating the pressure differential, this can be more challenging as it is influenced by a variety of factors such as the shape and design of the fan blades, the airfoil profile, and the ducting. One approach you could take is to use computational fluid dynamics (CFD) software to simulate the airflow through your model and analyze the resulting pressure distribution. This would give you a more accurate estimate of the pressure differential created by the fan.

Additionally, you may also want to consider conducting some physical tests on the fan in a controlled environment to gather more accurate data for your model. This could involve using a flow bench to measure the volumetric flow rate and pressure differential at different fan speeds.

I hope this helps and good luck with your project!