Passing by a semi truck on a highway
So I’m driving down the highway in my sedan on a speed of lets say 60 mph. Why is it that my car sways just before it passes or it passes me? Almost always where the semis first tire is (closest to the hood)? What forces are acting upon it? What could be a possible explanation to why it happens? Why is it only at that spot that the car sways?
automotive-engineering airflow car
edited 10 hours ago
Mahendra Gunawardena
4,46531752
asked 10 hours ago
Sal
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So I’m driving down the highway in my sedan on a speed of lets say 60 mph. Why is it that my car sways just before it passes or it passes me? Almost always where the semis first tire is (closest to the hood)? What forces are acting upon it? What could be a possible explanation to why it happens? Why is it only at that spot that the car sways?
automotive-engineering airflow car
edited 10 hours ago
Mahendra Gunawardena
4,46531752
asked 10 hours ago
Sal
82
New contributor
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
the truck can also shield you from the natural cross wind...
– Solar Mike
3 hours ago
add a comment |
So I’m driving down the highway in my sedan on a speed of lets say 60 mph. Why is it that my car sways just before it passes or it passes me? Almost always where the semis first tire is (closest to the hood)? What forces are acting upon it? What could be a possible explanation to why it happens? Why is it only at that spot that the car sways?
automotive-engineering airflow car
edited 10 hours ago
Mahendra Gunawardena
4,46531752
asked 10 hours ago
Sal
82
New contributor
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
So I’m driving down the highway in my sedan on a speed of lets say 60 mph. Why is it that my car sways just before it passes or it passes me? Almost always where the semis first tire is (closest to the hood)? What forces are acting upon it? What could be a possible explanation to why it happens? Why is it only at that spot that the car sways?
automotive-engineering airflow car
automotive-engineering airflow car
edited 10 hours ago
Mahendra Gunawardena
4,46531752
asked 10 hours ago
Sal
82
New contributor
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 10 hours ago
Mahendra Gunawardena
4,46531752
asked 10 hours ago
Sal
82
New contributor
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 10 hours ago
Mahendra Gunawardena
4,46531752
edited 10 hours ago
Mahendra Gunawardena
4,46531752
edited 10 hours ago
Mahendra Gunawardena
4,46531752
4,46531752
asked 10 hours ago
Sal
82
New contributor
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 10 hours ago
Sal
82
asked 10 hours ago
Sal
82
82
New contributor
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Sal is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
the truck can also shield you from the natural cross wind...
– Solar Mike
3 hours ago
add a comment |
the truck can also shield you from the natural cross wind...
– Solar Mike
3 hours ago
the truck can also shield you from the natural cross wind...
– Solar Mike
3 hours ago
the truck can also shield you from the natural cross wind...
– Solar Mike
3 hours ago
add a comment |
2 Answers
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As far as I understand a semi track travelling on highway has at least three different zones of interest. They are:
- Front
- Middle
- Back
Below are the three regions pictorially.
In order for the truck to pass through it diverts outwards air in front of the semi truck. The empty area middle (between the tractor and rear wheels) it creates vacuum which is reason sometime small car like the sedan get dragged toward the semi. The back of the semi also creates air void thus and air gets pulled in thus a small sedan could swayed into the lane the semi is travelling.
answered 9 hours ago
Mahendra Gunawardena
4,46531752
add a comment |
A truck speeding down a highway creates an envelope stream of high pressure air surrounding it.
This is basically a wake, composed of layers of high pressure shockwaves, created when the front of the truck, hood and cabin penetrate the still air and push it open.
This shockwave moves with the truck and after turning into a small turbulent tail at the backside dissipate slowly.
When you drive near a truck in passing, or it passes by you, your car cuts into the boundary of this wake.
Depending on your car's aerodynamics and your driving habits, the impact of incursion may become more pronounced at a certain point and angle. Some times this impact may be strong enough to steer the car closer to the truck. Or you my lose control by trying to avoid the collision.
I keep away from the big trucks as much as I can, or else try to anticipate the shock and be prepared.
answered 9 hours ago
kamran
3,6141410
add a comment |
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2 Answers
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active
oldest
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2 Answers
2
active
oldest
votes
active
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active
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votes
As far as I understand a semi track travelling on highway has at least three different zones of interest. They are:
- Front
- Middle
- Back
Below are the three regions pictorially.
In order for the truck to pass through it diverts outwards air in front of the semi truck. The empty area middle (between the tractor and rear wheels) it creates vacuum which is reason sometime small car like the sedan get dragged toward the semi. The back of the semi also creates air void thus and air gets pulled in thus a small sedan could swayed into the lane the semi is travelling.
answered 9 hours ago
Mahendra Gunawardena
4,46531752
add a comment |
As far as I understand a semi track travelling on highway has at least three different zones of interest. They are:
- Front
- Middle
- Back
Below are the three regions pictorially.
In order for the truck to pass through it diverts outwards air in front of the semi truck. The empty area middle (between the tractor and rear wheels) it creates vacuum which is reason sometime small car like the sedan get dragged toward the semi. The back of the semi also creates air void thus and air gets pulled in thus a small sedan could swayed into the lane the semi is travelling.
answered 9 hours ago
Mahendra Gunawardena
4,46531752
add a comment |
As far as I understand a semi track travelling on highway has at least three different zones of interest. They are:
- Front
- Middle
- Back
Below are the three regions pictorially.
In order for the truck to pass through it diverts outwards air in front of the semi truck. The empty area middle (between the tractor and rear wheels) it creates vacuum which is reason sometime small car like the sedan get dragged toward the semi. The back of the semi also creates air void thus and air gets pulled in thus a small sedan could swayed into the lane the semi is travelling.
answered 9 hours ago
Mahendra Gunawardena
4,46531752
As far as I understand a semi track travelling on highway has at least three different zones of interest. They are:
- Front
- Middle
- Back
Below are the three regions pictorially.
In order for the truck to pass through it diverts outwards air in front of the semi truck. The empty area middle (between the tractor and rear wheels) it creates vacuum which is reason sometime small car like the sedan get dragged toward the semi. The back of the semi also creates air void thus and air gets pulled in thus a small sedan could swayed into the lane the semi is travelling.
answered 9 hours ago
Mahendra Gunawardena
4,46531752
answered 9 hours ago
Mahendra Gunawardena
4,46531752
answered 9 hours ago
Mahendra Gunawardena
4,46531752
answered 9 hours ago
Mahendra Gunawardena
4,46531752
4,46531752
add a comment |
add a comment |
A truck speeding down a highway creates an envelope stream of high pressure air surrounding it.
This is basically a wake, composed of layers of high pressure shockwaves, created when the front of the truck, hood and cabin penetrate the still air and push it open.
This shockwave moves with the truck and after turning into a small turbulent tail at the backside dissipate slowly.
When you drive near a truck in passing, or it passes by you, your car cuts into the boundary of this wake.
Depending on your car's aerodynamics and your driving habits, the impact of incursion may become more pronounced at a certain point and angle. Some times this impact may be strong enough to steer the car closer to the truck. Or you my lose control by trying to avoid the collision.
I keep away from the big trucks as much as I can, or else try to anticipate the shock and be prepared.
answered 9 hours ago
kamran
3,6141410
add a comment |
A truck speeding down a highway creates an envelope stream of high pressure air surrounding it.
This is basically a wake, composed of layers of high pressure shockwaves, created when the front of the truck, hood and cabin penetrate the still air and push it open.
This shockwave moves with the truck and after turning into a small turbulent tail at the backside dissipate slowly.
When you drive near a truck in passing, or it passes by you, your car cuts into the boundary of this wake.
Depending on your car's aerodynamics and your driving habits, the impact of incursion may become more pronounced at a certain point and angle. Some times this impact may be strong enough to steer the car closer to the truck. Or you my lose control by trying to avoid the collision.
I keep away from the big trucks as much as I can, or else try to anticipate the shock and be prepared.
answered 9 hours ago
kamran
3,6141410
add a comment |
A truck speeding down a highway creates an envelope stream of high pressure air surrounding it.
This is basically a wake, composed of layers of high pressure shockwaves, created when the front of the truck, hood and cabin penetrate the still air and push it open.
This shockwave moves with the truck and after turning into a small turbulent tail at the backside dissipate slowly.
When you drive near a truck in passing, or it passes by you, your car cuts into the boundary of this wake.
Depending on your car's aerodynamics and your driving habits, the impact of incursion may become more pronounced at a certain point and angle. Some times this impact may be strong enough to steer the car closer to the truck. Or you my lose control by trying to avoid the collision.
I keep away from the big trucks as much as I can, or else try to anticipate the shock and be prepared.
answered 9 hours ago
kamran
3,6141410
A truck speeding down a highway creates an envelope stream of high pressure air surrounding it.
This is basically a wake, composed of layers of high pressure shockwaves, created when the front of the truck, hood and cabin penetrate the still air and push it open.
This shockwave moves with the truck and after turning into a small turbulent tail at the backside dissipate slowly.
When you drive near a truck in passing, or it passes by you, your car cuts into the boundary of this wake.
Depending on your car's aerodynamics and your driving habits, the impact of incursion may become more pronounced at a certain point and angle. Some times this impact may be strong enough to steer the car closer to the truck. Or you my lose control by trying to avoid the collision.
I keep away from the big trucks as much as I can, or else try to anticipate the shock and be prepared.
answered 9 hours ago
kamran
3,6141410
answered 9 hours ago
kamran
3,6141410
answered 9 hours ago
kamran
3,6141410
answered 9 hours ago
kamran
3,6141410
3,6141410
add a comment |
add a comment |
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the truck can also shield you from the natural cross wind...
– Solar Mike
3 hours ago