Aerodynamics of a Camper Trailer Through CFD
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- Опубликовано: 18 окт 2023
- Something a bit different. Following of from my hatchback model studies in CFD, this camper trailer suffered from a similar characteristic. At the rear there is significant drag caused by the lift through the idea of induced drag. Placing a flap or spoiler at the rear reduced the drag by a large 13%. Further modifications managed to produce a drag reduction of 30-35%. There is probably a little more left in it but this is the bulk of it.
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Out of curiosity, would it be possible to run a simulation on a car, with some of the windows partially rolled down, and see how would that compare against a fully rolled down window. For example, I like to roll down the passenger and rear passenger window 2 inches down while driving on a highway. The air doesn't blow into my face, and actually wrap around the rear interior of the car and blows gently into my neck.
Possible is, but the simulation will become highly heavy to process. I think this guy has a powerful Pc to run this simulations (3D simulation is, itself, heavy). Do it with all interior and details will require a very big and refined mesh.
Please do a video on roof luggage boxes, as some argue it is more fuel efficient to fit them with the slim side (conventionally at the rear) at the front. It would make die an interesting test I think. Thanks!
A while back I saw that someone had run a simulation of a boat on a trailer, the form drag was pretty low for a trailer but it made a lot of induced drag.
I just love your videos. Thanks for sharing!
Very nice. There are very few camping trailers looking like this on the roads of europe though, would be interesting to see a more common design.
This isn't really a mass market design. Most want a house like trailer, this is really just an insulated tent. To me an insulated tent sound pretty good.
That's really cool! If I had the software I'd look into how much of a difference having roof bars fitted would make, my ones even have vortex generator lookin nubs on the top of them!
Hi Nelson I just finished building the rear wing you mentioned on the hatch back design video... I had to put a lot of extra cross strength in it, as it was producing to much down force on the outer edges. We've done a fair bit of testing and fettling with it, and it works pretty good now.
I'd love to see an image... throw a link into the back of a long thread under an old video. I'll reply and then you can bin it, if that works.
What cfd software do you use?
These videos are so good. Exactly what I would do if I had this skill to model this out.
Supper interesting mate. I have always wondered what the turning vanes would do. I have a bullbar to fit to my fridge shaped 80s f150 and was looking at extending the trailing edge of the side and top round bar profile into a turning wing. If i ever do it ill do half at a time and string the crap out of it to see what it does.
One of the most unexpected serious cdf video ever hahaha
Hello Nelson! How do you manage to increase the visibility of the surface LIC. I mean, when i try to check the viscous lines with surface LIC and moreover with a variable, it´s hard to see how the viscous lines looks like. Thank you and your videos are terrific!!!
this where I learnt it, time stamped
ruclips.net/video/sjTH09Bc53M/видео.html
I've thought about making vortex generators along the top of mine to keep the airflow attached.
Good timing I’d had on my list to do a side by side comparison of airstream vs a typical European caravan we had a 25ft “white box” which even with anti sway on a breezy day was hell on wheels vs the airstream with it’s “implied” aero benefits ( there are no slab sides for a start) so although dragging maybe another ton with the toys we bring along these days the fuel economy is only 1-2 mpg less - airstream’s collar with Porsche recently touched on one solution we see in other caravans in Europe (eriba) drop the roof height to a “pop top” ala vw campervans and I think with their on board batteries they had reintroduced the flat underfloor cladding to shroud the chassis which older airstreams had. And can I ask what cfd package you are using? And yes teardrops are not particularly common in Europe but TAB who are one of the major suppliers used to make a larger twin axle version and I can see in a world of EV restricted tow weights the balance of aero/volume-size of a caravan vs range is really going to be a issue
openfoam
If you put vortex generators along the front sides would that help at all? They're much easier to come by... curious if sealing part of the trailer wheel wells would help too
The problem with drag on the caravan needs another solution.
If you pull a caravan with a normal car, the drag is high, If you have a high car like a SUV or Van, the drag is less. That is the reason, why trucks have spoilers or these aero tops on the roof and aero parts at the end of the cabin. These parts make the wind go other lines. if you can use a spoiler at the end of the car, that leads the wind high, the drag on the front of the trailer is less hard. The spoiler on the trailer will be great to have a better handling on the trailer caused by the downforce.
May you make a video on Split Spoilers?
rather than the wings on the corners, could you just use fences/endplates to prevent the flow spilling over?
The size of the fences would need to be as large as there is a pressure gradient. The fences could be tapered inwards to increase the pressure on the outside of the fences. but, this video is the smallest solution other than creating a radius on the corners
What program do you use for your aerodynamic simulations?
openfoam
@@nelsonphillips Thanks
Its very interesting i have built a teardrop for myself years ago very similar to the one you have modeled
I built it to the rear box dimensions of my 62 ej holden panelvan as thats the car i was towing with it
I averaged 110kmh with 14L to 100km with the teardrop in tow
And it really wasn't noticeable towing so i never bothered to improve the design as i jagged it first time
without teardrop average speeds of 110kmh with mileage of 12L to 100km
Now i still have the same teardrop and i have a new tow car a 74 Holden 1 tonner and i can really tell the difference between the two tow cars as far as drag both cars have the same engine so power levels are the same
I am putting this down to a lot lower roof line
A large empty tray thats creating a huge high Pressure point on the front of the van at speed
Would it be possible to have a closer look at the wings you developed for the sides id like to make and test something similar for my teardrop
As i noted my highway milage with camper at 19L 100km at 90 100kmh
Without camper i get higher crusing speeds of around 110kmh but mileage of 10lt 100km
So the teardrop is causing huge issues with drag id like to fix
yeah this makes sense. The panelvan covers most of the frontal area of the trailer, but for the ute its like driving two cars. There is also probably poor interaction with the trailer and the ute that are making thing worse.
hi, which program are you using to creat your models?
it just a basic solid modelling CAD software. Catia it is not
I saw you modeling your own F1. Can you pls lead me to where to start? Should I use catia?
@@rkoburakevo5596 i have never used catia but its the go to for surface modelling., however it is very expensive apparently. It depends on how you want to learn. there are plenty of decent yt tutorials.
@@nelsonphillips thank you
Caravan manufacturers don't seem do a lot for aero. Seems like a lot opportunity given how many there are on the road. A 30% reduction would do a lot for fuel consumption.
I assume manufactures do some, this is for the home builder that definitely do none
men will look at this and say "hell yeah"