Computer Aided Engineering
Physical model > Digital model > FEA/CFD > New digital model > New physical model
Why use Computer Aided Engineering?
Simulate your design in different scenarios without making physical changes to your model. Computer Aided Engineering has been widely applied to various engineering applications, and Physical Digital offers analysis on components as designed, as manufactured and as a comparison between the two.
The amount of data generated by Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) can be enormous. Analysis and interpretation of the results are challenging tasks, requiring good engineering knowledge and understanding of the problem. The results from FEA/CFD analyses can be used in:
- Conceptual studies of new designs
- Detailed product development
The CFD can help to answer the following questions:
- What is the overall flow pattern?
- Is there flow separation?
- Where do shock layers form?
- Calculate: Lift, Drag and Torque.
The FEA can be used to:
- Optimise designs
- Understand failures and help to solve problems
- Calculate deflection, loads, stresses and life of mechanical components
Some of the Computer Aided Engineering projects completed by Physical Digital include:
1. Scanning, Reverse Engineering and Aerodynamic Analysis of a King Air.
Figure 1: King Air – pressure distribution.
Figure 1 shows pressure distribution around The King Air. The Aircraft was 3D scanned and reverse engineered by our team. The King Air was simulated at Mach 0.6 - the simulation had to account for compressibility as well as turbulence effects. CFD enabled the client to investigate many different scenarios without flying the aeroplane, such as with flaps open and closed, and different angles of attack, speed and altitude. The client also gained further knowledge about the aircraft and the Computer Aided Engineering gave them a good indication how the plane can be modified and still operate safely.
2. Aerodynamic Analysis of a Wind Turbine Blade.
Figure 2: Structured mesh around a wind turbine aerofoil.
Figure 2 shows an aerofoil of a Wind Turbine Blade. A structured mesh was created to provide the best possible results. Physical Digital determined:
- Thickness to chord ratio
- Lift to drag ratio
- Insensitivity to roughness
3. Aerodynamic Analysis of a Filtered Air Supply System.
Figure 3: Filtered Air Supply System.
Figure 3 shows results from a Filtered Air Supply system. Using Computer Aided Engineering, Physical Digital simulated the internal flow in order to determine the filtered air volume flow rate, the pressure loss in the HEPA filter and the pressure increase generated by the fan.
4. Modal Analysis of a Micro satellite.
Figure 4: Micro satellite - modal analysis.
Figure 4 shows results from analysis of micro satellite vibration characteristics. All components were strong enough to cope with the stresses during a take-off but the client wanted to check the effect of vibrations from the rocket engines. The satellite had to meet natural frequencies of 45Hz and 90Hz.
100 modes were extracted capturing over 70% of total mass, the 10 most dominant modes in each direction were found and critical components for each mode were identified. It was found that the satellite had to be redesigned, because the natural frequencies of the satellite caused constructive superposition with the engine’s vibrations.
5. Aerodynamic Analysis and Design Optimization of a Truck.
Streamlines in Figure 5 and vectors in Figure 6 highlight large area of low pressure, flow separation and recirculation. Physical Digital was asked to use Computer Aided Engineering to advise on possible changes to the truck to reduce drag and increase efficiency.
Figure 5: Velocity streamlines around a truck.
Figure 6: Flow recirculation
6. Stress Analysis of a box beam.
Figures 7 and 8 show numerical and experimental results from bending a steel box beam. Physical Digital carried out a Computer Aided Engineering investigation of how to strengthen the beam without significantly increasing its mass. It was found that thin carbon fibre plate attached to the tensile flange of the beam increased the strength by over 30% with negligible mass increase.
Figure 7: FEA - beam.
Figure 8: FEA, validation of the results