Crumple zone difference in a collision

In summary, according to the speaker, newer cars have tighter crumple zones, which results in more damage to the car in a frontal offset collision.
  • #1
mike_J25
2
0
Hi there!

I would like to ask about different crumples zones in cars.

The thing is that modern cars have tighter crumple zones, which makes new cars decelerate faster than old ones in a crash of the similar speeds, in fact at 64km/h frontal offset crash test the new car might deform somthg like 50 cm, whereas the old one would crumple more than a meter. I was looking at a real life frontal offset car collisions and what i have noticed is that for example if two similar weight modern cars collide at the same speed, say 55 km/h - there would be one amount of damage, most of the time it is the same for both cars. But if we replace the second car with the old one of the similar weight, say produced in 1990, then we get something very different, at least that's what i have noticed. Even if the old car would be designed to withstand an offset collision at a 55km/h with another car of the similar weight and crumple so that passenger cell of the old car wouldn't deform, the very different picture can be observed in a collision with a modern car. It seems like when the old car collides with the new one of the similar weight, the crumple zone of the old car is being "eaten" by the new one and that results in more damage to the old car and less to the new one, which might be something like damage in a ~50km/h collision against a wall for the new car and ~60km/h for the old one instead of 55km/h for both.

Well as i think of it-it's like in an offset collision the crumple zone is one front side of the car. That front side might weigh something like 7-10 percents of the whole car's weight. So in a collision that side has a relatively small inertia, which means that it stops relatively fast and then acts like a spring or peace of rubber placed between two cars. And as that front side of the old car is softer than the new car's side - both cars use it as mutual crumple zone, which leaves the old car with smaller stopping time and the new one with a longer, than they both were originally designed to at such speeds- hence more damage to old one and smaller to the new one.

Is it a realistic scenario and am i right about that mutual crumple zone? because it really seems to me like that...
 
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  • #2
I think your explanation is plausible. "Equal and opposite reactions" would say that the resistance from a crumple zone on one car would act to slow the other car down. It would be interesting to try a simplified experiment to test this - perhaps toy cars with some sort of bumper made of aluminum foil or paper etc.
 
  • #3
thx.
 

FAQ: Crumple zone difference in a collision

How do crumple zones work in a collision?

Crumple zones are designed to absorb the impact of a collision by deliberately deforming or "crumpling" in a controlled manner. This helps to reduce the force of the impact on the passengers inside the vehicle.

What is the difference between a front and rear crumple zone?

The main difference between a front and rear crumple zone is their location on the vehicle. Front crumple zones are typically located in the front bumper and hood of a car, while rear crumple zones are found in the rear bumper and trunk. They are designed to absorb impact from different directions in a collision.

Can crumple zones prevent injuries in a collision?

Crumple zones can help to reduce the severity of injuries in a collision, but they cannot prevent them entirely. The purpose of crumple zones is to absorb the impact and distribute it over a larger area, which can help to protect the passengers inside the vehicle.

Are all vehicles equipped with crumple zones?

Most modern vehicles are equipped with crumple zones, but it is not a requirement for all vehicles. It is important to research the safety features of a specific vehicle before purchasing to ensure it has crumple zones and other safety measures in place.

How effective are crumple zones in reducing the severity of collisions?

Crumple zones have been proven to be effective in reducing the severity of collisions. In fact, studies have shown that vehicles with crumple zones have a 20-30% lower fatality rate compared to those without them. However, the effectiveness of crumple zones may vary depending on the speed and angle of impact in a collision.

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