Jump to content
Science Forums

Idea Release: vehicle efficiency


Recommended Posts

And,.....your point?

 

A bit remiss of me there.

 

Many years ago I had a small motorbike which I rode long distances. Overtaking large trucks doing over 80km/hr was a minor study in truck aero dynamics.

 

Dutchdivco, you have touched on the front and rear of the truck though have you considered the possible side forces of the prevailing winds ? and re the bike, I have a vague memory of hitting a major pressure wave/ increased wind speed (?) about a fith of the way back from the front of the truck (bike overtaking from the rear) On some occasions my underpowered bike could barely overcome the increase in wind.

Link to post
Share on other sites
It may be better to attach a sharks tail to the truck

 

Might make the steering a little giggle headed when the tail caught the wind :)

 

Sharks mouth and gills...Hmmm.

 

I wonder if there is much energy in the heat of the road ? (clear sky, full sun) Make the road one 'side' of the tunnel perhaps - Ground hugging skirts length ways between the tyres...

Link to post
Share on other sites
I do see that formula 1 racecars regularly incorporate such a tunnel in there designs. I also see that after someone put a fan in the tunnel, they outlawed putting any kind of mechanical device in there, which leads me to think it must have given an advantage. I find this hopeful.My truck is not anything like a formulae 1 race car, aerodynamiclaay. its about the opposite. As I say, I'm hoping, maybe, thats a good thing. I'll have a significant sized negative pressure zone, with a, I hope, significant amount of negative pressure.

 

With a bit of digging I can say that what they banned from formula 1 is ground effect. See lotus 78 in wikipedia. Short version is that with creating low pressure below the car helped the car stay pinned to the ground in even the fastest corners. So some later models used a vent to additionally vent the air out ot from the underside.

 

Also, I dont see any point of creating a tunnel trough the truck. The only thing it may do is create more drag. If you want to stick to the road create a low pressure below trough lowering it, but that would basically eliminate all the clearance :).

 

The areas on the truck that do most to the aerodynamics are front and back section.

Aerodynamic improvements & flow control boost fuel efficiency in heavy trucks

Link to post
Share on other sites

Again though, you would most likely loose more energy overcoming the added drag from the 'skirts' than you would gain from the device.

In all of the above ideas, you are adding weight and/or drag.

For example, the OP idea of getting 100lbs of lift for the vehicle. How much weight would be required for the structure, and how much additional drag? As a practiical issue, would you be adding any width to the vehicle, and if so, how much?

Link to post
Share on other sites

Not sure I'm following some of the points,here.The amount of weight I'm adding is very little.Certainly less than 100 lbs.Not using "skirts", though I am lowering the truck some, it won't be a "lowrider", tho! Anyway, its an experiment and I'll see whether it improves things, or not.I still THINK, at a minimum, it should reduce drag. I must admit tho, when i start researching aerodynamics at a certain point my eyes glaze over.Jim

Link to post
Share on other sites
Not sure I'm following some of the points,here
I must admit tho, when i start researching aerodynamics at a certain point my eyes glaze over

 

Dont worry, plod on.

 

Speaking of things aerodynamic - it was a couple of push bike mechanics who first designed and flew a heavyer then air flying machine. At the time there was a 'scientific' aircraft design effort going on involving large floating launch barges on rivers etc...

Link to post
Share on other sites

Not sure why you say I'm making it too complicated on myself. I maybe didn't explain; I raised the body off of the frame, for other modifications I was committed to making, and looking at the frame, and some of the other things I'm doing, it just kinda seemed to naturally fit in with it.Without going into a lot more detail, suffice to say, the tunnel or duct isn't that much work, time money or additional weight.So, if it doesn't give me much benefit at all, it won't be a terrible loss. Jim

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...