What happens if u run with your car into a wall..??!!
Well actually we all can imagine what happens then.but to stop such a retarded step we just apply brakes…just like that all when we drive our car,a wall stops our smooth drive i.e., air flow.. through which we need to break through..
Imagine…u are driving with speed say 80kmph in your topless car..we experience a lot of friction of air through our body right..this same friction is responsible for slowing down the car we are driving at that speed..this friction is called drag..this is also called air resistance and our cars have been designed to overcome that resistance….
We have our solution right in the heart of concept..AERO DYNAMICS..which is helping us to design cars to pass through that air wall..By reducing that resistance we can improve the fuel efficiency,speed,easy acceleration for the same amount of speed we travelled earlier..
For example..decorating our car with a stylish spoiler also have its part in aero dynamics by reducing the effect of air to lift the tyres of cars at higher speeds..hence some of the new cars have integrated spoilers as shown….
The above is an integrated spoiler design of a car
What is drag?
Drag is generated when a solid object moves through a fluid medium such as water or air. Drag increases with velocity — the faster the object travels, the more drag it experiences.. Drag has a direct effect on acceleration. The acceleration (a) of an object is its weight minus drag (D) divided by its mass (m)..
a = (W – D) / m
As an object accelerates, its velocity and drag increase, eventually to the point where drag becomes equal to weight — in which case no further acceleration can occur.. This means that as the car travels faster and faster, more and more air pushes against it, limiting how much more it can accelerate and restricting it to a certain speed….
How does all of this apply to car design? Well, it’s useful for figuring out an important number — drag coefficient. This is one of the primary factors that determine how easily an object moves through the air. The drag coefficient (Cd) is equal to the drag (D), divided by the quantity of the density (r), times half the velocity (V) squared times the area (A). To make that more readable:
Cd = D / (A * 0.5 * r * V^2)
The aerodynamic abilities of a car are measured using the vehicle’s coefficient of drag. Essentially, the lower the Cd, the more aerodynamic a car is, and the easier it can move through the wall of air pushing against it..
Let’s look at a few Cd numbers. Remember the boxy old Volvo cars of the 1970s and ’80s? An old Volvo 960 sedan achieves a Cd of .36….
The newer Volvos are much more sleek and curvy, and an S80 sedan achieves a Cd of .28 ..This proves something that you may have been able to guess already — smoother, more streamlined shapes are more aerodynamic than boxy ones..
Many have questioned the “unique” looks of the Toyota Prius hybrid, but it has an extremely aerodynamic shape for a good reason….
Among other efficient characteristics, its Cd of .26 helps it achieve very high mileage. In fact, reducing the Cd of a car by just 0.01 can result in a 0.2 miles per gallon (.09 kilometers per liter) increase in fuel economy..
At starting days of research on car designs, engineers experimented with different designs, knowing that streamlined shapes could help their cars go faster and handle better at high speeds. That eventually evolved into a very precise science of crafting the most aerodynamic race car possible. Front and rear spoilers, shovel-shaped noses, and aero kits became more and more common to keep air flowing over the top of the car and to create necessary downforce on the front and rear wheels..
This is the basic information about why cars have their design like that and about their drag coefficient’s necessity….
Lets learn about effect of height of Ferrari on its speed,effect of its box shape of our desi car WagonR on mileage and lots more..until then keep guessing your theories about the height and shape and speed relations..
All the best guys….
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