Comment by zamadatix
19 days ago
Very peculiarly, everyone seems to actually agree the handles are a little more aerodynamic. It's the possibility the manufacturer's teams (except marketing, apparently) could ever have also considered this as one of several benefits when choosing the design which is at such levels of doubt. Moreso, people are willing to dismiss it saying they'd want a certain type of source instead rather than just seeing whether that kind of source does also agree.
To complete the loop on the latter: Tesla's 2012 handle patent https://patents.google.com/patent/US9103143B2/en
> Conventional door handle designs typically have less than desirable aerodynamics due to protrusion of the exterior door handle from the surface of the door and the recessed area over which it spans. As the vehicle moves, these conventional door handles interrupt the smooth surface of the door and thereby increase the overall drag of the vehicle. Depending on the size, depth, and overall shape of the recessed area, for example, the corresponding area under the door handle further contributes to reduced aerodynamics of the vehicle. Designers have not focused on improving aerodynamics in this area as the exterior door handle seems relatively small and inconsequential.
> 104 in the retracted position provides both a smooth appearance and advantageous aerodynamic qualities when the vehicle is in motion
I'm starting to wonder if an interview with David Wheeler (what a name for a car patent) et al would even be believed here at this point.
If you read this thread, no one has claimed flush handles aren't more aerodynamic. What was claimed is that the aerodynamic benefits are negligible and as a result, that's not actually a serious consideration in choosing them.
Even the aero study done by range rover doesn't claim they're a meaningful improvement. It claims the handles came from the product design vision first.
> Depending on the size, depth, and overall shape of the recessed area, for example, the corresponding area under the door handle further contributes to reduced aerodynamics of the vehicle. Designers have not focused on improving aerodynamics in this area as the exterior door handle seems relatively small and inconsequential.
Aerodynamics is complicated. You should measure the actual impact rather than guess. "just make it smooth" is a rule of thumb, not a law. If we're following rules of thumb, my copy of Theory and Applications of Aerodynamics for Ground Vehicles specifically says this on the subject:
This is after the section where it recommends flush, airplane style handles as optimal, because again the original claim is that the magnitude of the improvement is negligible.
> If you read this thread, no one has claimed flush handles aren't more aerodynamic. What was claimed is that the aerodynamic benefits are negligible and as a result, that's not actually a serious consideration in choosing them.
I'm not sure how this differs from when I had previously started "Very peculiarly, everyone seems to actually agree the handles are a little more aerodynamic. It's the possibility the manufacturer's teams (except marketing, apparently) could ever have also considered this as one of several benefits when choosing the design which is at such levels of doubt".
Regardless, I continue to find myself in complete agreement w.r.t. this.
> Even the aero study done by range rover doesn't claim they're a meaningful improvement. It claims the handles came from the product design vision first.
My argument remains flush handles in the automotive industry are about more than just one thing alone (more specifically, that drag is indeed also one of those things). Hence I find myself rather lost as to how lack of being the first reason for Range Rover should strike drag as having already been shown as one of their other listed reasons. As far as I can conceive, being about more than one thing alone inherently necessitates some of those reasons are not always to be given as a first reason. Similarly, I don't follow why only the first reason might be held as non-negligible.
> Aerodynamics is complicated. You should measure the actual impact rather than guess. "just make it smooth" is a rule of thumb, not a law.
Other engineers in the field are well aware aerodynamics is a fickle beast and they are not commonly guessing their vehicle aerodynamics by rule of thumb, as you already seem to be very familiar with based on mentioning the Range Rover aero study. Of course, I don't like to leave such a claim uncited or unsourced (regardless how familiar it seems to all already) so here is an SAE paper backing claims Tesla did indeed extensively test the aerodynamics of every external component (for the same vehicle the patent is referring to) rather than guess the impact of exterior elements by rule of thumb https://www.researchgate.net/profile/Robert-Palin/publicatio...:
"Aerodynamic optimization is a major contributor to the overall efficiency of an electric vehicle and the close integration of the Design and Engineering groups at Tesla Motors was specifically arranged to process design iterations quickly and enable the fully informed development of the exterior surfaces at a very rapid pace... Following aerodynamic optimization at the overall shape level, focus switched to optimization of production parts, and every external component of the Model S has been examined in great detail searching for aerodynamic performance, since areas that may seem insignificant in isolation can rapidly accumulate to have a substantial impact on the whole."
> If we're following rules of thumb, my copy of Theory and Applications of Aerodynamics for Ground Vehicles specifically says this on the subject...
We're not just following rule of thumb, but everything in the comments prior still appears to align with this passage anyways. One indeed does not need to make the door handle optimally flush to make a design choice which is aerodynamically beneficial. Clearly, however, the additional possible efficiency is not completely negligible (or an ignored factor) in flush door handle design consideration by many manufacturers in order to make exclusive way for reasons other than drag. One does not even need to conclude this from any of the evidence, to repeat the relevant portion of the prior citation instead:
"Following aerodynamic optimization at the overall shape level, focus switched to optimization of production parts, and every external component of the Model S has been examined in great detail searching for aerodynamic performance, since areas that may seem insignificant in isolation can rapidly accumulate to have a substantial impact on the whole."
.
Again, I'm not trying to argue drag is the only reason (or even that it's the primary reason). Just that claims the additional drag is negligible or saying that flush handles aren't about drag does not redefine what the auto makers themselves say about drag being a reason.