MR2 Owners Club Forum banner

Status
Not open for further replies.
41 - 60 of 178 Posts

·
Administrator
Joined
·
42,296 Posts
I have always suspected that the 84-86 front nose was more aerodynamic then the 87-89. The 87+ nose "looks" more aero and has a more pleasing shape, but the slant looks to show that the 'leading edge' of the bumper has a big effect on the flow later on down the line.
I am certain that by adding the sunshade over the back window that will seriously effect flow over the butress and the flow out of the engine bay.

What is the measurement of the rear deck to the bottom of the rear deck wing? I believe working off of memory that it is 1"-1 /12".
 

·
Registered
Joined
·
1,051 Posts
How long does it take to run a simulation on a simple model like the one being used?

Is it possible to run some sort of CFD analysis on detailed model like mine?



I've really got to get some updated, nicer renders.
 

·
Registered
Joined
·
1,051 Posts
Right now the model is being held for carolina new be who's made me an offer for the rights to use to model. It would be unfair to share the model freely.

It's got 224,108 poly's when it's all smoothed for rendering. The model superpilun is using cant be more then a few hundred, right? Would it crash the program trying to run an analysis on something like this? The low poly model is only a few thousand poly's (and modeling details irrelevant to airflow could be deleted or simplified to lower the poly count)
Heres an idea what the unsmoothed mesh looks like:
 

·
Registered
Joined
·
1,051 Posts
The lights pivot up and down on a slider in 3ds max, I just had them up in the renders to show the detail.
Heres another one with them down


Theres no underbody/engine bay structure right now, because I didnt model it with CFD analysis in mind, but it would be very easy for me to model. I have done full interiors/engine bays before.
Another Toyota, the GT-one I modeled with full engine bay (still semi-in progress)

 

·
Administrator
Joined
·
42,296 Posts



1. top of spoiler is fast moving air flow being pulled along faster by the 'reverse' flow that is at the second arrow point.
Move the spoiler back aka Plumley Spoiler and you increase the pull of the flow over the top of the spoiler because you are putting the spoiler in that sweet spot low pressure (blue) area at the second arrow.

2. This section is way off. I think by altering number 4 you will reverse flow to the back.

3. Installing the sun shield here should move the super low pressure area (front of roof - Blue) back a bit and increase low pressure area over the engine lid thus helping to suck out engine bay air.

4. That area drops down too far in your rendering.

5. Look at the blue low pressure area right there. That is where we cut the hood for the PapaL style hood vent. That would help suck the air out of the radiator area in a big way. This proves that the front of the hood is a better place for a vent then more traditional area like the middle of the hood like the MK2 guys do.

6. The high pressure area developed by the 1984-1986 flat bumper is pushing up the flow of air early. keeping it smoth over the eyes and helping to create the low pressure area over the hood. Wonder how much effect the turn signal holes have on this...

7. Anyone remember my ill fated rear radiator install? Look at the air flow... the air is being pushed BACK into the license plate. This is bad and is what led to the lack of flow out of the trunk. This has also made me question my mounting of the exhaust pipes for my V8 MR2 in this area.
 

·
Premium Member
Joined
·
10,238 Posts
We need to get someone to completely redo the Mk I model. I think that some of the conclusions we're drawing may be a little more complicated than the accuracy of the model is good for. I think if we're going to be drawing these sort of conclusions we should remake the model to the best scale possible.

I'd like to say I can do it but my trial version of SW expired and I can only use it at school, which is 45 mins from my home during the summer. I've been thinking about buying a student version, but I probably won't use it for anything else, since we will be using CATIA exclusively for FSAE this fall.

Anyone have any suggestions? Also, does anyone know if Cosmos (specifically FloWorks) comes with the student version? That would suck if it didn't.
 

·
Registered
Joined
·
6 Posts
Cross posted from http://forums.twobrutal.com/showthread.php?t=8538 where this thread is also being watched with great interest:

Very interesting thread you've got there Bill - like you I'd love to see the effect of a Plumley spoiler and papal vent, as the trackday car I'm currently building has both those features

The high pressure area ahead of the front skirt makes me hopeful the other aero mod I've got planned will be useful too - a horizontal plate splitter fitted to the underside of the nose, extending maybe 100-150mm forward of the front skirt and rearward to maybe 150mm behind the base of the radiator. Don't know if it'll unbalance the car at speed though, with the added front downforce ( or reduced lift anyway ) not being matched by a similar change at the rear, unless the Plumley is a lot more effective than the standard location. My Plumley has its leading edge about 20mm behind the edge of the bootlid ( pics here http://forums.twobrutal.com/showthre...?t=7581&page=3 ) - if I do get an excess of front downforce I may try fitting a Gurney flap to the rear spoiler too.

It would also be interesting to see the effect of a rear diffuser - though as you've already pointed out the rear underbody on the model is far to low, and should really be curved to mimic the exhaust silencer.

Lots of food for thought though
 

·
Administrator
Joined
·
42,296 Posts
bentheswift said:
We need to get someone to completely redo the Mk I model. I think that some of the conclusions we're drawing may be a little more complicated than the accuracy of the model is good for. I think if we're going to be drawing these sort of conclusions we should remake the model to the best scale possible.

I'd like to say I can do it but my trial version of SW expired and I can only use it at school, which is 45 mins from my home during the summer. I've been thinking about buying a student version, but I probably won't use it for anything else, since we will be using CATIA exclusively for FSAE this fall.

Anyone have any suggestions? Also, does anyone know if Cosmos (specifically FloWorks) comes with the student version? That would suck if it didn't.
I agree.
I have access to supercomputers that could do this modeling for us if we have all the data prepared. I work for the University of Virginia and we have a pretty damn good Engineering department http://www.mae.virginia.edu/ . I have loads of contacts there. I am willing to bet that if we can get all the data together I can go over there one evening and use the supercomputer with help from either Faculty or students and get the data in a form we can post.
 

·
Premium Member
Joined
·
2,106 Posts
Discussion Starter #57
ben the swift, on my trial student version of sw 2005, all i have to do to use it is change the date in windows to less than a year after the date i installed it. If you want to more accurately model the car, I'll be more than happy to flow it in FloWorks.
 

·
Registered
Joined
·
1 Posts
Ive come accross from Twobrutal aswell :)

I dont know much about These AreoDynamic Programs or the physics about it but im posting on here to see what happens if someone can put the Eurosport Front on





And this rear bumper on.



http://rpmlab.com/images/rearside.JPG

With that front on and that back on it might help a little.

I would like to see it anyway
 

·
i overtake on roundabouts
Joined
·
3,775 Posts
indeed, would love to know how to and more importantly understand the results those programs/sims show.
would be interesting to see the feral put through it.
 

·
Registered
Joined
·
1,434 Posts
ive got a copy of the latest version of the model (thanks to superpilun :)) but he is using a later version of solidworks than i have access to, so i cant use it :(

and unfortunately im still not getting the original model to calculate, i think theres something wrong with my floworks setup as opposed to the model itself. so il either have to abandon my efforts, or attempt to get the original model working

if i do get it working, i intend to do a lot more looking at modified solutions than at the standard airflow, so if people want to investigate things like bonnet vents, bodykits, splitters, wings, etc il look into those. but it might be a while before i can get this sodding thing to work!!
 
41 - 60 of 178 Posts
Status
Not open for further replies.
Top