The drag coefficient is a common measure in automotive design as it pertains to aerodynamics. Drag is a force that acts parallel and in the same direction as the airflow. Reducing the drag coefficient in an automobile improves the performance of the vehicle as it pertains to speed and fuel efficiency.
Which car has the best aerodynamics?
- Audi A6: 2011-present (Cd 0.26)
- BMW i8: 2014 (Cd 0.26)
- Mazda3 Sedan: 2012-present (Cd 0.26)
- Mercedes-Benz B-Class: 2012-present (Cd 0.26)
- Nissan GT-R, 2011â€“present (Cd 0.26)
- Peugeot 508, 2011â€“present (Cd 0.25)
- Hyundai Sonata Hybrid, 2013-present (Cd 0.25)
- Toyota Prius, 2010-present (Cd 0.25)
Automotive aerodynamics is the study of the aerodynamics of road vehicles. Its main goals are reducing drag and wind noise, minimizing noise emission, and preventing undesired lift forces and other causes of aerodynamic instability at high speeds.
drag is the wind resistance (force) that acts against the car as it is moving forward. Less drag means higher speeds, more drag means lower speeds. On a race car downforce is good because it is a force created through aerodynamics that pushes that car in a vertical direction towards the race track.
Drag is the force of wind or air resistance pushing in the opposite direction to the motion of the object, in this case, the cyclist and the bike. The two types of aerodynamic drag that act against a cyclist are: pressure drag. skin friction drag.
Therefore, the easiest method of decreasing drag is to lower the coefficient of drag of the car . Therefore, vehicle designers change specific aspects of the shape of the body of the vehicle in order to reduce the total aerodynamic drag and thus increase fuel economy.
We can also think of drag as aerodynamic resistance to the motion of the object through the fluid. There is an additional drag component caused by the generation of lift. Aerodynamicists have named this component the induced drag. It is also called "drag due to lift" because it only occurs on finite, lifting wings.
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid.
In fluid dynamics, the drag coefficient (commonly denoted as: , or ) is a dimensionless quantity that is used to quantify the drag or resistance of an object in a fluid environment, such as air or water. The drag coefficient is always associated with a particular surface area.
The drag equation states that drag D is equal to the drag coefficient Cd times the density r times half of the velocity V squared times the reference area A. For given air conditions, shape, and inclination of the object, we must determine a value for Cd to determine drag.
|Cd||Drag Coefficient||No units|
|r||Density of air||kg/m3|
The drag coefficient Cd is equal to the drag D divided by the quantity: density r times half the velocity V squared times the reference area A. The drag coefficient then expresses the ratio of the drag force to the force produced by the dynamic pressure times the area.
Induced Drag is an inevitable consequence of lift and is produced by the passage of an aerofoil (e.g. wing or tailplane) through the air. Air flowing over the top of a wing tends to flow inwards because the decreased pressure over the top surface is less than the pressure outside the wing tip.
The terminal velocity depends on the weight, the drag coefficient, the air density and the reference area. The air density has a typical value of 1.229 kg/cu m. Typical values of drag coefficient for a parachute is about 1.75, compared to 0.75 for a typical model rocket.
Drag depends directly on the mass of the flow going past the aircraft. The drag also depends in a complex way on two other properties of the air: its viscosity and its compressibility. These factors affect the wave drag and skin friction which are described above.
Cycling Aerodynamics & CdA - A Primer. A riders aerodynamic drag is a critical factor in the speed he can achieve at a given level of power output and therefore a given level of fitness.
Use the terminal velocity formula, v = the square root of ((2*m*g)/(ρ*A*C)).
- m = mass of the falling object.
- g = the acceleration due to gravity.
- ρ = the density of the fluid the object is falling through.
- A = the projected area of the object.
- C = the drag coefficient.
The lift coefficient (CL, CN or Cz) is a dimensionless coefficient that relates the lift generated by a lifting body to the fluid density around the body, the fluid velocity and an associated reference area. A lifting body is a foil or a complete foil-bearing body such as a fixed-wing aircraft.
Pressure drag is caused by the air particles being more compressed (pushed together) on the front-facing surfaces and more spaced out on the back surfaces. This is caused when the layers of air separate away from the surface and begin to swirl – this is called turbulent flow.
The drag coefficient is a number which aerodynamicists use to model all of the complex dependencies of drag on shape, inclination, and some flow conditions. The drag coefficient Cd is equal to the drag D divided by the quantity: density r times reference area A times one half of the velocity V squared.