The R&D project involved a range of aerodynamic simulations for a new generation electric flight design. The project focused on optimizing multirotor three-bladed propellers’ efficiency within impeller ‘barrel’ geometry with further DFM.
A hi-tech company involved in new-generation flight designs conducted a series of bench tests of its three-bladed propellers (both single and twin-rotor) and contacted EnCata to optimize its overall efficiency. Such propellers, embedded in a stationary impeller, are designated to increase the air pressure within a ‘barrel’ and are sometimes called “Bartini well.”
EnCata’s simulation engineers faced a task where the engine type (size, power, and torque) and three-bladed props were pre-defined. We needed to start with these parameters and develop a new impeller design/shape and optimize the distance between the two propellers.
Our Role
CFD numerical simulations
Applied research
CAD design
Design for manufacturability (DFM)
3D printing
Documentation development
Technologies Used
FEA/FEM analysis
3D printing topology optimization
CFD simulations / analysis
For Enterprises
• R&D + design + manufacturing under ONE roof • Scale up and down your team • Intergrated hardware + software development • New technologies and research
Initially, the research team had to build the simulation model with adequate accuracy to verify the experimental data. Much effort was put into the validation of the testing procedures to reproduce test bench results.
While single-prop set-up is somewhat easy to optimize, the twin-rotor design required optimization for both the distance between the propellers and ‘barrel’ shape / wall-tip separation. Upon running a large set up of stationary aerodynamic simulations, the EnCata simulations engineers determined optimal rotor positioning and measured the set-up’s max efficiency with two propellers.
Further work encompassed CAD and DFM works to enable 3D-printing of the new impeller walls. The challenge here lied in the impeller size (nearly 0.6 meters in diameter). A 3D CAD model had to be adopted for assemblability (we used some ‘honeycomb’ structure to reduce weight) without compromising structural rigidity.
Experimental validation of the CFD analysis is the key in any similar project. The data obtained through the aerodynamic simulations must be validated and verified through tests, and physical tests should provide necessary boundary conditions and inputs for computer simulations.
Results and Benefits
This early-stage development project involved a range of aerodynamic simulations intended to design an essential module for a new generation electric flight design, along with CAD and DFM work.
The customer left EnCata with the designed module and CAD documentation, which was ready to be embedded in their flight demonstrator. Our CFD simulations and aerodynamic expertise provided the definite answer on how to position the multirotor propellers within its impeller.
This project was a good example of incorporating EnCata’s R&D research competence into novel flight design.
1.77 kg
impeller weight achieved
24.6%
thrust efficiency gain achieved at 3000 rpm by optimising the propeller placement within the “aerodynamic well”