AirShaper

For more information, visit https://www.airshaper.com or email info@airshaper.com
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In this video we’ll explain flow separation (or boundary layer separation).
In our previous video on boundary layers, we saw that the air close to the surface will stick to it, forming a boundary layer. But in some cases, it can become too difficult for the air to follow the curvature of the surface, causing it to detach. Let’s have a look at why this can happen.

When you look at air flowing across a flat plate, as in our previous video, the free stream velocity remains constant. Because of Bernoulli’s equation, which states that pressure changes with velocity, this means the pressure gradient in the X-direction is more or less to zero. Also, the pressure is imposed onto the boundary layer and so doesn’t really change much in the direction perpendicular to the surface either. That means the pressure gradient in both the x and y direction are close to zero.

But when the air flows around a curved surface, it speeds up and slows down. Take the flow around a cylinder for example: at the front, the pressure is the highest as the air comes to a complete standstill – this is the stagnation point. As the air then curves around the cylinder, it speeds up and this creates a drop in pressure. As the pressure goes down with increasing x, this is a negative pressure gradient, which is good: the air is being pushed downstream, overcoming the friction in the boundary layer, which gradually builds up.

The maximum velocity is reached somewhere around the midpoint of the cylinder, after which the air starts to slow down again. This means the pressure gradient is now reversed: as the air travels across the surface, the pressure goes up. This is what is called an “adverse” pressure gradient and the air is no longer driven but obstructed by the pressure difference: it has to flow into regions with higher pressure.

If the pressure gradient is positive or zero, as in the case of the flat plate, then the velocity gradient perpendicular to the wall is positive: the further you move away from the wall, the higher the velocity. But when the air travels against an adverse pressure gradient, the velocity profile is pushed back and this reduces the velocity gradient at the wall.

At some point, the velocity gradient becomes zero, which is the point where the flow separates or detaches. Beyond this point, the velocity profile is zero both at the wall, because of the no-slip condition, and at the inflection point, which is where the velocity crosses from negative into positive. In the negative velocity region, between the surface and the inflection point, the air flows in a direction opposite to the main flow  – this is called a recirculation. The separated flow will now surf on top of this recirculation flow and the boundary layer and wake will continue to grow, which can have a negative effect on drag.

In reality, shapes can be much more complex than cylinders and flows can detach and reattach in various locations. Even on a smooth wing, the flow can detach and reattach. So, this is very much a 3-dimensional challenge and getting it right requires a careful analysis and optimization of local and global pressure gradients.

Also, keep in mind that flow separation can happen in both laminar and turbulent boundary layers. Turbulent boundary layers, however, carry more momentum and will typically stay attached to the surface further downstream compared to a laminar one – just check our video on golf ball dimples or vortex generators to learn more.

Flow Separation - Boundary layer separation explained

For more information, visit https://www.airshaper.com or email info@airshaper.com
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In this video, we explain what a boundary layer is.

Let’s look at two extremes first:
No-slip condition: no matter how smooth the surface is, the flow will always stick to it, having a flow velocity of zero on the surface of the object.
Free stream velocity: the velocity of the undisturbed air, far away from the object

To understand what happens in between these two extremes, let’s look at air flowing across a flat plate. As the undisturbed air meets the leading edge of the plate, it will locally stick to it because of the no-slip condition. As the air moves or slides across the plate, this layer or air sticking to it will grow thicker. This region, where the air moves slower than the free stream velocity, is called the boundary layer and it is mainly determined by the viscous forces. Outside of the boundary layer, the viscous forces are much less important and sometimes even ignored in fluid modeling

You can have a laminar boundary layer, with layers of air moving parallel to the surface, or a turbulent boundary layer, filled with vortices featuring velocity variations in all directions.
If the incoming airflow is laminar itself and if there are no disturbances that can trip the flow, the boundary layer will start off as laminar. As the air continues to move along the plate, so does the distance traveled from the leading edge. If we use this distance to calculate the Reynolds number, it’s clear that the Reynolds number will continue to rise as we move further down the plate. 

When the Reynolds number crosses a critical value, which can be different for each application or geometry, the laminar boundary layer will start to transition into a turbulent one. The velocity profile of both types is very different and can have a large impact on the total friction & pressure force on the object.

In applications like airplanes, where shapes are smooth and streamlined, the goal is to maintain a laminar boundary layer as long as possible: a turbulent boundary layer increases the friction drag and typically is thicker than a laminar one, which increases the effective thickness and thus the pressure drag of the wing.

In applications with less streamlined shapes, like sports athletes or golf balls, it can be beneficial to trip the boundary layer and make it turbulent: turbulent boundary layers carry more momentum and will push the separation point further downstream – that’s the reason golf balls have dimples and athletes wear special suits or even shin tape, reducing the wake they leave behind.

What is a Boundary Layer - Laminar and Turbulent boundary layers explained

The boundary layer is a thin region of slow-moving air next to the surface of an aerodynamic body and can be the main source of friction drag.

What is a Boundary layer?

To learn more about:
- Boundary layers: https://youtu.be/TwOxa9rAOfE
- Flow separation: https://youtu.be/HfICmKv9SzE
- Golf ball aerodynamics: https://youtu.be/KzXcglAhxps

In this video, we'll explain the aerodynamics behind curved free kicks, corners, and so on! Want to bend it like Beckham? Then stay tuned!

When you kick the ball off center, you'll give it a spin around the vertical axis. At one side, the surface is spinning against the airflow, so the relative velocity between the surface and the air is increased. This slows down the air and also moves the separation point upstream.

At the other side, the surface is spinning in the same direction as the airflow, reducing the relative velocity. This reduces friction and boundary layer buildup and pushing the separation point further downstream.

First way to explain the force - Bernoulli:
the faster moving air will feature lower pressure, creating a suction effect bigger than on the other side. This generates a net lateral force.

Second way to explain the force - momentum:
the wake behind the soccer ball is pulled towards the side of the forward spinning side. Because of Newton's law of action and reaction, this generates an equal but opposite effect on the ball.

The effect described in this video is called the magnus effect.


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The AirShaper videos cover the basics of aerodynamics (aerodynamic drag, drag & lift coefficients, boundary layer theory, flow separation, reynolds number...), simulation aspects (computational fluid dynamics, CFD meshing, ...) and aerodynamic testing (wind tunnel testing, flow visualization, ...).

We then use those basics to explain the aerodynamics of (race) cars (aerodynamic efficiency of electric vehicles, aerodynamic drag, downforce, aero maps, formula one aerodynamics, ...), drones and airplanes (propellers, airfoils, electric aviation, eVTOLS, ...), motorcycles (wind buffeting, motogp aerodynamics, ...) and more!

For more information, visit www.airshaper.com

Soccer aerodynamics - How to curve a ball

Part 1: https://youtu.be/K2jgsgihZ_w
Tuft testing on a Vokswagen Beetle: https://youtu.be/CGmqdXKgBiQ

In this second video on the Porsche Taycan Aerodynamics, we’ll take the car to the street to compare tuft movement to simulation data.
Special thanks to the Porsche Centre in Mechelen, Belgium, for letting us play with this fantastic car 😊
https://www.porsche.com/belgium-mechelen

In our last video, we had equipped the Porsche Taycan with a number of tuft

Rear window & spoiler

On the rear window and spoiler, none of the tufts move. This is because the flow in that area stays nicely attached & laminar. There is some slow-down of the flow due to the “negative” curvature of the window, but this doesn’t lead to separation.

Rear wheels
The rear wheels create a turbulent zone which extends downwind (causing a lot of movement of the tufts on the rear bumper) and also upward (creating movement above the wheel arch as well). The latter extends all the way to the rear spoiler.

A-pillar and side window
As the air makes its way from the front wind shield to the side window, it curves around the A-pillar. In doing so, a vortex is created which locally pushes the air upward, just behind the A-pillar. This upward motion extends further downwind at the top of the side window as well.

Front wheels
The front wheels also create a turbulent zone which splashes out upward. Further downstream, this zone is countered by the air coming off the front hood, which creates a zone of attached air curving downward on the flanks.

Headlamps
The headlamps are located in a “pocket” in the bodywork. As the air jumps out of this pocket, it locally separates from the bodywork and leaves behind a local bubble of separated, turbulent flow. This can be seen in both simulation & tuft movement.


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The AirShaper videos cover the basics of aerodynamics (aerodynamic drag, drag & lift coefficients, boundary layer theory, flow separation, reynolds number...), simulation aspects (computational fluid dynamics, CFD meshing, ...) and aerodynamic testing (wind tunnel testing, flow visualization, ...).

We then use those basics to explain the aerodynamics of (race) cars (aerodynamic efficiency of electric vehicles, aerodynamic drag, downforce, aero maps, formula one aerodynamics, ...), drones and airplanes (propellers, airfoils, electric aviation, eVTOLS, ...), motorcycles (wind buffeting, motogp aerodynamics, ...) and more!

For more information, visit www.airshaper.com

Porsche Taycan Aerodynamics Part 2: Road testing

For part 2, check this link: https://youtu.be/kyHjWGnrByQ

In this video, we will go over the aerodynamic features of the Porsche Taycan and prepare it for road testing! Special thanks to the Porsche Centre in Mechelen, Belgium, for letting us play with this fantastic car 😊
https://www.porsche.com/belgium-mechelen

In our last video, we had optimized the rear of the Porsche Taycan using our Aerodynamic Shape Optimization technique (to have it generate more downforce), In this video, we get up close with all the other special features of this car (underfloor, diffuser, wheels, …)


Underfloor

At the front splitter, the air jumps underneath the car and accelerates as it gets into the channel formed by the road surface and the underfloor of the car. This increased velocity will reduce the pressure, creating a suction force pulling the car downward (which is good for handling).
On electric cars, the underfloor can be made very smooth & flat, as it sits below the battery pack and as they have very little exposed components. So the air maintain its velocity and connect with the diffuser at the rear, where it connects to the wake behind the car, reducing drag, increasing downforce and so on.


Wheels
Wheels are a major source of aerodynamic drag on cars. They are large, unshielded elements rotating through the air, acting like a mixer. Not only do they generate drag themselves, they also create turbulent air downstream, which can increase drag / reduce performance elsewhere.

Porsche has fitted the car with air curtains, which are channels in the front bumper. The opening at the front accepts the high pressure are at the nose of the car which is then sped up to exit at high velocity through a slot at the rear of the front bumper, just ahead of the front wheel. This creates a curtain, shielding the turbulent air coming off the rotating wheel.

Another feature are the aerodynamic rims. To limit their drag, they created a rim which is more “covered” than a regular rim. Secondly, the profile of the spokes has been designed in such a way that the air nicely slides across the spokes, instead of being pushed away by more blunt spoke shapes.

And finally, Porsche also air deflectors in front of the wheels: these are small “ramps” that divert the air so it doesn’t hit the wheels directly (where it would create a large wake). These are present both at the front & the rear wheels.


Rear spoiler
The active rear spoiler will automatically extend when you are going fast enough to improve downforce & aero balance of the car.


Coolers
Air is forced through the coolers and this represents an energy loss. So when you don’t need full cooling power, it’s good for efficiency to (partially or fully) close the entrance to the coolers. This will reduce the energy lost on air going through the coolers and will make the air go around the car instead.


Ride height
The Porsche Taycan has an extremely low drag coefficient of 0.22 and one of the tricks to achieve this is to lower the ride height of the car. Lowering the ride height at low speeds would be impractical towards ground clearance, speed bumps etc, so it is lowered dynamically as the car picks up speed. A lower ride height also has a positive impact on the handling of the car, as downforce typically increases with reduced ride height.


Tufts
We equipped the car with tufts, which are small strands of wool that will align themselves with the local orientation of the airflow. This allows us to analyse flow patterns and see where the air has detached and/or has become turbulent.


Next video
Stay tuned for our next video, where we’ll take the car for a ride and compare the tuft patterns with what we saw in simulations!


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The AirShaper videos cover the basics of aerodynamics (aerodynamic drag, drag & lift coefficients, boundary layer theory, flow separation, reynolds number...), simulation aspects (computational fluid dynamics, CFD meshing, ...) and aerodynamic testing (wind tunnel testing, flow visualization, ...).

We then use those basics to explain the aerodynamics of (race) cars (aerodynamic efficiency of electric vehicles, aerodynamic drag, downforce, aero maps, formula one aerodynamics, ...), drones and airplanes (propellers, airfoils, electric aviation, eVTOLS, ...), motorcycles (wind buffeting, motogp aerodynamics, ...) and more!

For more information, visit www.airshaper.com

Porsche Taycan Aerodynamics Part 1: aero features explained

For more about measurement techniques, check this series on how wind tunnels work:
- Part 1: https://youtu.be/L1AYo9Mk1EI
- Part 2: https://youtu.be/qqYiz1eo-F4
- Part 3: https://youtu.be/yA9FdqJdiKk


Pitot tubes are small devices used on aircraft, turbo machinery and even Formula One cars to measure flow velocity, or rather, measure pressure to calculate flow velocity.

Basic theory
The Bernoulli stated that the pressure goes gown as the velocity goes up, when following a particle along its flow path. For incompressible fluids, this can be stated using the following equation:

P_static + 0.5*rho*v² = P_total

P_static: this is the static pressure, which is the pressure you would feel when traveling along with the flow without disturbing it.
0.5*rho*v²: this is the dynamic pressure, which basically relates to the kinetic energy of the fluid.
P_total: this is the total pressure, which is the pressure you would measure when you bring the flow to a complete standstill – therefore, it’s also called the stagnation pressure.

The interesting thing about this equation is that we can reshuffle it to calculate the velocity based on the static pressure and total pressure:
V = sqrt( (2*(P_total-P_static) ) / (rho) )


Measurement probes
So how do we measure the static and total pressure? Well, you guessed it – we can use a pitot tube!
At the front of the pitot tube, which points directly into the wind, the air comes to a complete standstill. This means that the pressure measured there equals the total pressure.
At the side of the pitot tube, the openings are parallel to the flow and so it is not slowed down. A “static ring” as it is called is often used in these kinds of probes.  The pressure measured here equals the static pressure.

Logging the pressure difference
The next step is to obtain the difference between the static pressure and the total pressure to calculate the dynamic pressure. You can do this in an analogue way, by connecting both tubes coming from the measurement openings to a manometer or a membrane. The difference in water height or membrane deflection can then be used to calculate the pressure delta and then the velocity. Or you can hook the tubes to a pressure transducer and use the electric output signal to log the data.

Limitations
Keep in mind that a pitot tube can only measure the relative wind speed, so the difference in velocity between the object and the air (called the airspeed in aviation terms). So if you want to know the absolute speed of your object versus the real world (called the ground speed in aviation), you’ll also need to measure the velocity of the wind itself. Or cheat, and use your GPS 😊
Also important is to keep the pitot tube pointing straight into the wind, although more advanced versions are able to measure not just wind speed but also the angle of attack of the wind. –7
Pitot tubes come in various shapes and forms, like this elbow version I got from the lovely Katharina Kreitz of Vectoflow – they actually make pitot tubes using 3D laser sintering to create complex internal channels for custom applications.

Use in applications
Pitot tubes are used in countless applications. Airplanes are the most obvious, where they log the airspeed. But they are also used on the front of Formula One cars, to have a good reference velocity to compare to wind tunnel data. They’re also key to measure & calibrate the wind speed of wind tunnels, just ahead of the test section. And I’ve been told pitot tubes have even been used to measure the airflow in kitchen cooker hoods – not kidding you!

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The AirShaper videos cover the basics of aerodynamics (aerodynamic drag, drag & lift coefficients, boundary layer theory, flow separation, reynolds number...), simulation aspects (computational fluid dynamics, CFD meshing, ...) and aerodynamic testing (wind tunnel testing, flow visualization, ...).

We then use those basics to explain the aerodynamics of (race) cars (aerodynamic efficiency of electric vehicles, aerodynamic drag, downforce, aero maps, formula one aerodynamics, ...), drones and airplanes (propellers, airfoils, electric aviation, eVTOLS, ...), motorcycles (wind buffeting, motogp aerodynamics, ...) and more!

For more information, visit www.airshaper.com

Pitot Tubes - Measuring Flow Velocity

To see actual show cases of adjoint shape optimization:
- Porsche Taycan render: https://youtu.be/-fBXwx_n10I
- Aptera optimization: https://youtu.be/WpFNwfHwFn4

In this video, we'll discuss Aerodynamic Shape Optimization using the adjoint technique.


Aerodynamic Optimization
In aerodynamic simulations, the airflow around an object is chopped up in small pieces called cells within a mesh. The surface of the object is also chopped up into small pieces called surface cells with nodes on the corners.

To obtain the total drag or lift of the object, we need to integrate the pressure & friction forces on all these local surface cells to get the total value. This indicates that the position of each individual node has an influence on the final drag & lift on the object.

The objective function, therefore, has thousands if not millions of input variables: the X, Y and Z coordinate of each individual node. To obtain the local gradient, you would need to move one node individually and then re-run the entire calculation to calculate the local gradient. With that information, you know whether to push the node inward or outward to increase or decrease the objective function. Once you have obtained all these local gradients, you can put them together into what is called a surface sensitivity map.

As you can imagine, re-running the entire simulation for each node displacement can become very expensive. Luckily, there is something called the adjoint technique.

Adjoint
The adjoint technique allows you to calculate all of these local gradients, or sensitivities, in one single simulation. Here's how this works:

- Normal aerodynamic simulation (primal or forward simulation):
After the computational mesh has been generated, the flow field is typically initialized using a fixed value (zero or something else). Then, the properties defined at the boundary conditions (like an inlet flow velocity for a virtual wind tunnel) propagate through the domain. After enough small time steps, the solution will have converged to a stable flow field.

- Adjoint simulation (dual or backward simulation)
Starting from the aerodynamic simulation data, the adjoint simulation will take small "time" steps. It calculates backward from the objective function to see how each node position affects this objective function. Based on these results, we can then calculate all the local gradients and construct the sensitivity map.

So instead of running a full aerodynamic simulation for each local gradient calculation, which would be prohibitively expensive, we can now calculate all the gradients with just two simulations: the normal (primal) and the adjoint (dual) simulation.

Morphing
The next step is to use the input of the sensitivity map and start implementing it: move the surface inward or outward based on what the map tells you. Once you have morphed the 3D object, you can re-run the aerodynamic simulation to see how much the objective value has changed. You can then also re-run the adjoint simulation to create a new sensitivity map and to the morphing again.

With each cycle, you will get closer to the most optimal shape for your object. You can do this for the entire object or you can define a design space in which the algorithm can operate.

Porsche Taycan
Interestingly enough, the adjoint optimization technique - when asked to increase downforce - starts to create the iconic ducktail spoiler that Porsche has been applying for years.

For more information or to run your own optimization project, just contact AirShaper at info@airshaper.com


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The AirShaper videos cover the basics of aerodynamics (aerodynamic drag, drag & lift coefficients, boundary layer theory, flow separation, reynolds number...), simulation aspects (computational fluid dynamics, CFD meshing, ...) and aerodynamic testing (wind tunnel testing, flow visualization, ...).

We then use those basics to explain the aerodynamics of (race) cars (aerodynamic efficiency of electric vehicles, aerodynamic drag, downforce, aero maps, formula one aerodynamics, ...), drones and airplanes (propellers, airfoils, electric aviation, eVTOLS, ...), motorcycles (wind buffeting, motogp aerodynamics, ...) and more!

For more information, visit www.airshaper.com

Aerodynamic Shape Optimization - The Adjoint CFD Method

Learn more about:
- Reducing pickup truck drag: https://youtu.be/E0ass_AxloM
Road testing the Porsche Taycan: https://youtu.be/kyHjWGnrByQ

How to use coastdown testing for drag measurement

What is coastdown testing?
A coastdown test is one of the most common tests in the automotive industry. It is a way of measuring the mechanical and aerodynamic resistance that acts on a vehicle. 
The vehicle is accelerated to a particular speed and once constant, the clutch is engaged. The vehicle is then allowed to slow or ‘coast’ down in neutral. By recording the distance travelled and the time taken, the aerodynamic drag can be calculated (see also: https://airshaper.com/videos/what-is-aerodynamic-drag/video/DbIIw-WryHY)

How to calculate the drag coefficient
See also: https://airshaper.com/videos/what-is-a-drag-coefficient/video/bEgoZ_dAg7o
For simplicity, let’s assume the vehicle is slowed down by only two forces: 1) mechanical resistance and 2) aerodynamic resistance. Mechanical resistance is primarily due to the rolling resistance of the tyres and therefore remains constant, regardless of the vehicle’s velocity. Whereas aerodynamic resistance changes with the square of speed. In other words, drag force has less of an affect at low speeds, but a large affect at high speeds.

Newtons 2nd law states that the acceleration of an object is directionally proportional to the sum of the forces acting on it. Applying this to our simplified coastdown test, we get an equation which includes a rolling resistance coefficient, Crr and a drag coefficient, Cd.
So how do you calculate the value of two coefficients from a single equation with only one measurement? First, let’s look at two extremes:

1)   No aerodynamic resistance
If the vehicle completed a coastdown test in a vacuum, where there was no air resistance, then only the mechanical resistance would slow it down. Therefore, the car would decelerate at a constant rate, resulting in a linear deceleration curve.

2)   No mechanical resistance
If the vehicle had no rolling resistance and so only the aerodynamic resistance was slowing it down, then the deceleration curve would be non-linear. The car would decelerate faster at high velocity and slower at low velocity.

In reality, the measured curve from your coastdown test would be a combination of both. You can then adjust the coefficients to alter the shape of the curve until the measured curve matches the predicted curve. This process is called least squares regression. Overall, you will end up with a value for aerodynamic drag and a value for mechanical resistance.

As ever in aerodynamics, it is unfortunately not that easy. In reality, the equations mentioned above are much more complex. They need to account for factors such as mechanical resistance in the drivetrain, ambient conditions, wind direction, gravitational force and rotational inertia.

Yet, despite its complexity, coastdown tests are an industry standard for determining the performance of a vehicle. So, if you want to find out the drag coefficient of your car, why not use your cell phone’s GPS and some Excel magic to conduct your own coastdown test?

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The AirShaper videos cover the basics of aerodynamics (aerodynamic drag, drag & lift coefficients, boundary layer theory, flow separation, reynolds number...), simulation aspects (computational fluid dynamics, CFD meshing, ...) and aerodynamic testing (wind tunnel testing, flow visualization, ...).

We then use those basics to explain the aerodynamics of (race) cars (aerodynamic efficiency of electric vehicles, aerodynamic drag, downforce, aero maps, formula one aerodynamics, ...), drones and airplanes (propellers, airfoils, electric aviation, eVTOLS, ...), motorcycles (wind buffeting, motogp aerodynamics, ...) and more!

For more information, visit www.airshaper.com

Drag Measurement  - Coastdown Testing

How to use coastdown testing for drag measurement

For more videos on how wind tunnels work:
- Part 1: https://youtu.be/L1AYo9Mk1EI
- Part 2: https://youtu.be/qqYiz1eo-F4

In this third video in our series "How Wind Tunnels Work" we look at wind tunnel measurement techniques - both some of the most widely used as well as some innovative ones.

Forces & moments
One of the most important output parameters of a wind tunnel test are the forces & moments on the object. To obtain these, the object is typically connected to a 3D force balance, which is a device that can measure the forces and moments around three perpendicular axes.

It's important to make sure that the influence of the connection part does not disturb the airflow too much, which is why they're often given an aerodynamic profile.

Surface pressure measurement
To measure the static pressure on the surface, you can use pressure taps. These are small holes drilled perpendicularly to the surface with a tube fitted to each hole in the model. These tubes are then sent to a pressure transducer which is typically located outside the wind tunnel, where the pressures are measured & logged.

If you want to measure the pressure on many locations on the surface of your object, you'll quickly end up with a huge set of cables that needs to be led outside. This is something you need to take into account during the design of your prototype.

Alternatively, you can work with miniaturized pressure transducers that fit within your model and then convert the measurements into digital data which is then sent to the outside world via a single cable to save space.

3D flow measurement
- Smoke: one of the oldest & most common techniques is to release smoke upstream of the object to trace the path of the air. This can lead to very insightful information in terms of where the separation point is located, what the size is of certain vortex structures and so on. But it's quite difficult to determine local flow velocities, so over the years, a number of alternatives have been developed.
- PIV - particle image velocimetry: tracer particles are released upstream of the area of interest. The size, density, ... of these particles are chosen in such a way that they follow the real flow nicely, without dropping to the ground or disturbing the flow pattern. They are then illuminated, typically in a 2D plane, using a laser. Then, they're filmed perpendicularly to that plane by high-speed cameras. By tracking & tracing the position of the individual particles between consecutive shots, one can reconstruct their path and calculate the velocity vector and flow field.
- 3D measurement probes: by measuring the differential pressures at the head of these multi-hole probes, you can obtain the static pressure and total pressure, the angle of attack and the velocity. If you then trace the position of the probe itself in 3D, you can reconstruct a 3D flow field.

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The AirShaper videos cover the basics of aerodynamics (aerodynamic drag, drag & lift coefficients, boundary layer theory, flow separation, reynolds number...), simulation aspects (computational fluid dynamics, CFD meshing, ...) and aerodynamic testing (wind tunnel testing, flow visualization, ...).

We then use those basics to explain the aerodynamics of (race) cars (aerodynamic efficiency of electric vehicles, aerodynamic drag, downforce, aero maps, formula one aerodynamics, ...), drones and airplanes (propellers, airfoils, electric aviation, eVTOLS, ...), motorcycles (wind buffeting, motogp aerodynamics, ...) and more!

For more information, visit www.airshaper.com

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