How do you explain the aerodynamic benefits of your vehicle designs? ?

1 Drag and Lift

Drag is the force that opposes the motion of your vehicle through the air. It reduces your speed, increases your fuel consumption, and generates heat and noise. Lift is the force that acts perpendicular to the direction of your vehicle's motion. It can either push your vehicle up or down, depending on the shape and angle of your vehicle's body and wings. Lift can improve your handling and cornering, but too much lift can make your vehicle unstable and prone to flipping. Your goal as an automotive designer is to balance drag and lift to achieve the best performance and safety for your vehicle.

2 Coefficient of Drag

One way to measure how aerodynamic your vehicle is, is to use the coefficient of drag (Cd). This is a dimensionless number that represents the ratio of drag force to the dynamic pressure of the air. The lower the Cd, the less drag your vehicle experiences. The Cd depends on factors such as the shape, size, surface roughness, and orientation of your vehicle. Some common ways to reduce the Cd of your vehicle are to streamline its body, minimize its frontal area, smooth its edges, and use spoilers, diffusers, and undertrays to control the airflow around and under your vehicle.

3 Pressure Distribution

Another way to understand how aerodynamics affects your vehicle is to look at the pressure distribution on its surface. Pressure is the force exerted by the air molecules on your vehicle. High pressure means more force, and low pressure means less force. The difference between high and low pressure areas creates a net force on your vehicle, which can be either drag or lift. For example, if the air pressure is higher at the front than at the rear of your vehicle, you have a drag force. If the air pressure is lower above than below your vehicle, you have a lift force. You can use pressure distribution diagrams to visualize how the air flows around your vehicle and how it creates different forces on different parts of your vehicle.

4 Boundary Layer

The boundary layer is the thin layer of air that sticks to the surface of your vehicle due to friction. The boundary layer can be either laminar or turbulent, depending on how smooth or rough the surface is and how fast the air flows over it. Laminar boundary layer means that the air flows in parallel layers with little mixing. Turbulent boundary layer means that the air flows in irregular and chaotic patterns with more mixing. Generally, laminar boundary layer creates less drag than turbulent boundary layer, but it can also detach from the surface more easily, creating a large wake behind your vehicle and increasing drag. You can use devices such as vortex generators, dimples, or grooves to control the transition from laminar to turbulent boundary layer and reduce drag and wake.

5 Reynolds Number

The Reynolds number (Re) is another dimensionless number that characterizes the flow of air over your vehicle. It depends on the density, viscosity, velocity, and length of the air and your vehicle. The higher the Re, the more turbulent the flow. The lower the Re, the more laminar the flow. The Re can help you predict how the air will behave around your vehicle and how it will affect the drag and lift forces. You can use the Re to compare different vehicles or different conditions of the same vehicle, such as speed, altitude, or temperature.

6 Wind Tunnel Testing

Wind tunnel testing is a method of simulating the aerodynamic conditions of your vehicle in a controlled environment. You can use wind tunnel testing to measure the drag, lift, and pressure distribution of your vehicle, as well as to observe the flow patterns and boundary layer behavior. Wind tunnel testing can help you validate your design choices, identify potential problems, and optimize your vehicle's aerodynamics. You can also use wind tunnel testing to demonstrate the aerodynamic benefits of your vehicle to your clients, colleagues, or potential buyers, by showing them how your vehicle performs under different scenarios and how it compares to other vehicles.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?