Timoj

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i know this would add some complexity to the making the vehicle but think about the spoiler of a model x. how it comes out and then hides with the body. imagine if there was something like this for the cybertruck. a wiper hidden on the top of the hood towards the end of the windshield and when it rains or you want to use the wiper it would come out like the model x spoiler and onto the windshield. i think this would be cool.
A spoiler at the bonnet/windscreen interface could also create a air curtain to require less wiping.

 

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From lights to apex is a flat surface, no where to hide…
did you miss the long discussion on the compartment needed between the forward wind deflector and the windscreen?
 


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The length of the BAW in a stowed vertical position will not add drag enough to be worth mentioning. This is because the dominant form of drag in a wheeled vehicle velocity range is "form drag" (from the shape and frontal area) and not "skin drag" (from the length of the vehicle exposed to airflow). The vertical wiper however might have a secondary effect in that it doesn't allow for more laminar flow over the a pillar edge, resulting in more turbulence where the the airflow recombines behind the vehicle, which in turn will add to form drag. Just like the mirrors do now too.

I wonder how many extra batteries they need to add since the wiper and mirrors have been added back on the CT? 2-5%? That could be up to a grand of extra batteries, all just to compensate for the loss of range. :(
 
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Timoj

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The length of the BAW in a stowed vertical position will not add significantly to drag enough to be worth mentioning.
Ok, so why have they folded it in half like switchblade?
 

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Ok, so why have they folded it in half like switchblade?
They didn't, they just took off the top part like I said a few times, for whatever reason. Maybe so we talk about it for free publicity? :)

I suppose at least the mirrors are removable for that reason to reduce drag.

I'm sure the "half BAW" its not to reduce drag though, I could run it through my fluid dynamics simulation, but I'm not sure if it will even show much of a difference. The frontal area of the BAW is causing the drag regardless, especially so as it's sitting in the accelerated airflow from the hood etc. as well as the overall frontal area of the CT that extends all the way back to the roof apex,

CT CFD Aero.PNG
 
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Tinker71

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They didn't, they just took off the top part like I said a few times, for whatever reason. Maybe so we talk about it for free publicity? :)

I suppose at least the mirrors are removable for that reason to reduce drag.

I'm sure the "half BAW" its not to reduce drag though, I could run it through my fluid dynamics simulation, but I'm not sure if it will even show much of a difference. The frontal area of the BAW is causing the drag regardless, especially so as it's sitting in the accelerated airflow from the hood etc. as well as the overall frontal area of the CT that extends all the way back to the roof apex,

CT CFD Aero.PNG
Very cool. Thanks for sharing. I assume this model shown is without the BAW and mirrors? So does Coefficient of drag account for the secondary disruption in air flow? CD is good for comparing different vehicles of similar size, but I suspect a more absolute standard measurement for comparison would be better, maybe watts to overcome wind resistance at 100 kph.?

Those 2 tailpipe looking things look horrible. Are they? Anyway to reduce them?
 

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Would be interesting to put the CT and RV(with air) through windtunnel testing to work out the optimal heights of each.
 


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Ok, so why have they folded it in half like switchblade?
If they did, it might reduce the aerodynamic cost of the BAW.

Those 2 tailpipe looking things look horrible. Are they? Anyway to reduce them?
What tailpipe things? The towhooks?

-Crissa
 

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Very cool. Thanks for sharing. I assume this model shown is without the BAW and mirrors? So does Coefficient of drag account for the secondary disruption in air flow? CD is good for comparing different vehicles of similar size, but I suspect a more absolute standard measurement for comparison would be better, maybe watts to overcome wind resistance at 100 kph.?

Those 2 tailpipe looking things look horrible. Are they? Anyway to reduce them?
Sorry, that picture is not my actual CFD simulation that I did a few years back now, I just found it on my phone and used it to demonstrate the flow over the a-pillars where the BAW is mounted.

The tailpipes as well as the other "cloud" looking things are turbulent airflow. The rear of the CT is a typical Kammbach design which is meant to keep airflow on the rear roof and bed laminar, by having abrupt edges where that airflow suppresses the more turbulent rear low pressure zone.

There are two interesting features of the airflow you can't see on that picture. One is the front air dam created by the flat nose configuration that actually helps seperate airflow around the nose of the vehicle making it appear round to the airflow, and two the way the airflow going up the windscreen is sucked around to the back roof and bed and helps keep the rear flow laminar. The rest is pretty standard fair really, that roof apex makes things harder than they need to be, something round up there would help. But will stay that way for aesthetics.
 

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If they did, it might reduce the aerodynamic cost of the BAW.


What tailpipe things? The towhooks?

-Crissa
From the airflow model there are 2 turbulence areas that stick way off the back. They look like tailpipe emissions. Obviously not tho. I assume since there are 2 it is from air rejoining after going underneath and around the wheels.
 

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From the airflow model there are 2 turbulence areas that stick way off the back. They look like tailpipe emissions. Obviously not tho. I assume since there are 2 it is from air rejoining after going underneath and around the wheels.
Which airflow model?

Grab a screenshot, please. Sometimes a picture really is a thousand words.

-Crissa
 

 
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