Vs BMW F10 5er vs Mercedes Benz W212 E-Klasse Body Rigidity

[Sunny]

And no the F10 got 3rd Place in 2010, read the Link next time:

You seriously cannot read can you or you are just deliberately just trolling. The link clearly says winners as in plural (not singular) and lists 5 cars. Like all 5 won, they just listed BMW 3rd. Can some mod seriously ban this troll. This has to be trolling cause I refuse to believe someone can be this bad at reading comprehension and still use internet. Or maybe not.

 

[K-A]

Dude, you are hilarious. Thank you for amusing me.

No, you're wrong again (or making stuff up again).

Here you go, read the link.

Audi A8 bags this year’s Euro Car Body Award

Here’s the summary: (1st to 14th)

1.Audi A8
2.Lexus LFA
3.BMW 5 Series
4.Volkswagen Sharan
5.Alfa Romeo Giulietta

6.Opel Meriva
7.Aston Martin Rapide
8.Volvo S60
9.Honda CR-Z
10.Ferrari 458 Italia

11.Citroën C4
12.Ford Grand C-Max
13.Saab 9-5
14.Samsung SM5

.... With this, and you "misreading" the W212's 180MPa figure being there only to tell the reader that 75% of it's HSS is GREATER THAN 180MPa.. well.. it speaks for itself.

 

[Zafiro]

Guys, still arguing? Lets go the circus together...

Anyway, you guys can throw the Automotive Circle International to the garbage. It doens't mean much anyway since the 5-series wasn't one of the contenders back in 2009. If it was the 5er could have won (or lose) but we will never know though. Therefore it fails for a comparison between 5-series and E-class.

 

[K-A]

Somewhat, but it did handily beat out the 5 GT, which is very similar to the F10. Who knows if the F10 could have won, but fact is that the W212 did win, and it's a good supporting claim as to how well and advanced the body on that car is.

 

[Sunny]

Guys, still arguing? Lets go the circus together...
.

Not any more, that troll is on my ignore list.

 

[Zafiro]

Somewhat, but it did handily beat out the 5 GT, which is very similar to the F10. Who knows if the F10 could have won, but fact is that the W212 did win, and it's a good supporting claim as to how well and advanced the body on that car is.

Its already in the garbage can and you need a better argument before I pick it up the comparison between 5er and E-class have failed.
I think you guys need to stop this and move on

 

[K-A]

Sunny officially bowed out and as I expected, I claim victory.

After a call out on fabricating two things: F10 "tying" for the Award, and the W212 laughably only using 180MPa steel (when the exact Article line was in fact stating that 75% of the car uses STRONGER than 180MPa), I think the best bet is to ignore me.

 

[Zafiro]

Sunny officially bowed out and as I expected, I claim victory.

Thats not very mature now is it. Sunny did the right thing since neither of you are going to convince each others who is right or wrong.

 

[K-A]

Well, the irony was worth pointing out. But, I'll give him that, in that we weren't gonna convince each other of anything, so it's best to just let it go.

Note that when I did make mistakes, I admitted it, and I did ask questions in my quest to learn more about this, but answers back weren't very helpful, leading me to believe that my studies in this field and evidence to support my claims, are at least enough for me to not doubt my "verdict", between these two cars.

 

[Centurion]

This is what I was saying. I feel that torsional rigidity is more related to the CHASSIS strength, which I believe the F10 has more of. My belief, based on what I can gather, is that the body rigidity, which is what we see from the Crash Test data (the IIHS Pictures, roof Strength Stats, etc.), and what the EuroBody Award appears to focus on, is what I believe the W212 has over the F10, based on the information at hand.

I see what you mean but these days very few cars have a chassi frame and thus the drive train components are just bolted onto the body frame.

 

[K-A]

I would also like to point out, that Sunny was wrong in claiming that the 5 GT uses steels that are 1550-1700 MPa.

See here:

http://members.steel.org/AM/Templat...NTENTID=38294&TEMPLATE=/CM/ContentDisplay.cfm

The STRONGEST steels the 5 GT uses are 1000 MPa, while the STRONGEST steels the W212 uses are 1500 MPa.

Not to mention, the 5 GT only uses 48% of HSS (1000 MPa included in that), while the W212 uses a record setting 72% (1500 MPa included in that).

Just more points to prove mine, and show that many of those that were used against my points, were in fact false.

 

[Giannis]

Sunny officially bowed out and as I expected, I claim victory.

Oh my...

I asked all of you guys, like a hundred times to behave yourselves. Even if you don't agree with someone, you can't force them your opinion, which goes for both sides. There are facts and "facts" and there's an actuall science behind the calculation of the torsinal rigidity of a certain construction, in which both the material (yield/ultimate strength) and the geometry play an important role.

You can't just judge based only on pictures on just the torsinal rigidity figure. It's a whole bloody science which can't be reduced to some random photos or a kN/deg number. Engineers tend to spend a considerable percentage of their lives trying to learn such things and one could consider this pointless discussion an insult!

I am asking for the last time, both sides to stop this joke. There's no point and no chance that you will finally agree. K-A, you have an engineer and a very-well informed auto industry guy telling you facts and trying to explain you some engineering and automobile design fundamentals. You can't just base you opinion on some awards or whatever.
Do some research, try to find what exactly torsinal rigidity and the other forms of rigidity are and how are they calculated before continuing this discussion. This is utterly childilish right now.

One more post like the last ones and this thread will also get locked.

I hope you guys understand.

 

[martinbo]

This is exactly why I stay out of crash test / safety discussions. The generally available information is too open to broader interpretation and lends itself to be manipulated to one's own ends in an argument. Structural engineering is a highly specialised discipline and one that can only be covered when most of the details are readily available.

This is an unfortunate outcome of discussion (one member putting another on ignore, thereby leaving the other to "claim" a so-called victory - when in actual fact it's the forum that ends up losing).

 

[Giannis]

http://www.google.com/url?sa=t&rct=j&q=stiffness%2Bmatrix%2Bbeam&source=web&cd=1&ved=0CB0QFjAA&url=http%3A%2F%2Fwww.asiri.net%2Fcourses%2Fmeng412%2Fm412sm04ex1sol.pdf&ei=R_CnTqK6M8nKsgaeoPWGDg&usg=AFQjCNFiErZU5d76wicpCbQIYKpjzIpG2Q

Take a look at the above link guys.

You can see the stiffness matrix, [K], for a simple beam. You can there see the E, I and L quantities. E is the Poisson ratio which has to do with the material. I is the momment of inertial and L is the length. That way you can see that the stiffness is a function of the material, the geometry and the dimensions. So, reducing it to a number and comparing this to other stiffness results is not enough to make a proper judgment on a simple beam. Let alone a whole car...

 

[Giannis]

Also, in a few words, why the most importand form of rigidity/stiffness in a car is the torsional one: Because when a car takes a turn, you need a very stiff chassis, in order not to alter the suspension geometry. A car with a "soft" chassis will suffer small changes in the suspension geometry which affect the handling of the car to a very important extent.

Also, if I am not mistaken, and please correct me if I am wrong, in order to measure a car's torsional rigidity, you remove the wheels and mount the car on a special device. This device loads the car with two opposite momments, one in the front end, and one in the rear end. Then the cars resistance to torsion is measured. Of course, the suspension has a very important role, as a car with a "soft" suspension will produce a higher torsional rigidity compared to the same car with a much harder suspension. That is because a soft suspension will absorbe a bigger percentage of the applied torque than the softer suspension. Again, if I am wrong, please correct me!

 

[klier]

^^^ That's exactly how it's done. Like trying to squeeze the moisture out of the frame.

 

[Monster]

The measurement of the torsional stiffness of chassis will only involve the bare chassis, so the suspension parts are removed during the measurement process. One end of the chassis will be fixed and the other end is free to allow for any deflection when a rotational force is applied to that end.

We have engineering programs such as CATIA or Solidworks which allow engineers to find out all the measurements they need. After some poor souls have modelled every single component of the car and have assembled all the parts together, they can use this model to conduct various simulations to find out whatever they want. The material properties for each component eg young modulus, density, poisson's ratio, damping co-eff, thermal expansion co-eff......are stored with the 3D model so the virtual results are extremelyaccurate.

 

[K-A]

K-A, you have an engineer and a very-well informed auto industry guy telling you facts and trying to explain you some engineering and automobile design fundamentals.

Problem is, they were wrong on many of their facts (3 straight in fact, in which I proved in my last posts), and I feel that I've brought to the table many more solid, and tangible backings/facts to my theory.

Nobody's saying that this stuff is easy, or that we can form an absolute answer, but when I provide: E-Class side by side pictures showing much better safety cage performance than the F10 next to it / Roof strength numbers of the E showing 21,000 lbs of force resistance VS F10 15,000 lbs / W212 using (Industry leading) 72% HSS and usage of a maximum of 1500 MPa Tensile Strength Mega High Strength Steel VS 48% HSS in the 5 Series GT and usage of a maximum of 1000 MPa UHSS (using the 5 GT as an example, as no doubt the F10 is very similar in this regard, you can diagnose these steels for yourself via the IIHS side crash/roof footage/data) / The E being Awarded in its safety cage (over a 5 GT, with F10 coming at #3 in the next year), then I feel that I have more than enough facts on my side (visual, analytical, statistical, factual), to support my theory/believe/opinion on this matter.

Most of the posts from the other end haven't been giving me figures or proof that the F10 has a stronger body, except for the Torsional Rigidity figure (which is very important, and alone is enough to keep from calling the E conclusively stronger), in which we still don't have an exact number posted on the F10, just an assumption based on the "55% stronger than the E60" statement. What they have done, is make an effort to discount my facts by way of panning my assumptions just for the sport of it.

But, c'est la vie.

 

[Monster]

Problem is, they were wrong on many of their facts (3 straight in fact, in which I proved in my last posts), and I feel that I've brought to the table many more solid, and tangible backings/facts to my theory.

Nobody's saying that this stuff is easy, or that we can form an absolute answer, but when I provide: E-Class side by side pictures showing much better safety cage performance than the F10 next to it / Roof strength numbers of the E showing 21,000 lbs of force resistance VS F10 15,000 lbs / W212 using (Industry leading) 72% HSS and usage of a maximum of 1500 MPa Tensile Strength Mega High Strength Steel VS 48% HSS in the 5 Series GT and usage of a maximum of 1000 MPa UHSS (using the 5 GT as an example, as no doubt the F10 is very similar in this regard, you can diagnose these steels for yourself via the IIHS side crash/roof footage/data) / The E being Awarded in its safety cage (over a 5 GT, with F10 coming at #3 in the next year), then I feel that I have more than enough facts on my side (visual, analytical, statistical, factual), to support my theory/believe/opinion on this matter.

Most of the posts from the other end haven't been giving me figures or proof that the F10 has a stronger body, except for the Torsional Rigidity figure (which is very important, and alone is enough to keep from calling the E conclusively stronger), in which we still don't have an exact number posted on the F10, just an assumption based on the "55% stronger than the E60" statement. What they have done, is make an effort to discount my facts by way of panning my assumptions just for the sport of it.

But, c'est la vie.

I have a few things to point out, the side by side comparison do tell a compelling story but you have to think if both cars are hit at the same height relative to the ground? The F10 might have a lower ride height than the W212, so more of the impact are concentrated at the B pillar instead of letting the side sills channel some of the load. Besides the visual impact, how well did both cars protect the passengers? As in which structure absorbed more energy during the crash? After all there is no point having an ultra stiff structure when all the forces are transferred directly to the people inside.

I will agree the E has a stronger roof structure.

I am always a bit suspicious when they quote % in the press release statement. 72% in terms of what? Mass, number of components? Like Giannis has pointed out, if you study the link he posted, you will see tensile strength is only one of the FIVE variables that determines the bending deflection of a simple metal beam, anda monocoque consist of many of these, in complex shapes, and they are all linked together so to pick out one specific point out of a complex integrated system will not give you a proper understanding. The use of higher strength steel allows engineers to achieving the set strength targets with a smaller, lighter design. The SAME level of structural strength can be achieved by increasing the cross sectional area of the component at the cost of extra weight. It is all about playing with the variables in the equation.

As for the award, the W212 won in 09 with a completely different group of competitors than 2010, the W212 won with 38.5/50 points correct? The F10 might have score just as well or slightly higher but failed to win it out right because of the stronger competition in 2010, you have to remember it has to face the LFA.

In the end after all these discussions, it all comes down to two things which really matters, how much energy can the crash structure absorb in an impact, and how well does the entire safety cage protect the occupants inside from any external intrusions. That is what a chassis is suppose to do in an event of an impact, all these discussions about who uses the stronger steel by how many % are interesting but it is not the end of the matter.

I wish I have more time to look up all these stuff in detail, perhaps in a few days time I will.

 

[Sunny]

This is exactly why I stay out of crash test / safety discussions. The generally available information is too open to broader interpretation and lends itself to be manipulated to one's own ends in an argument. Structural engineering is a highly specialised discipline and one that can only be covered when most of the details are readily available.

This is an unfortunate outcome of discussion (one member putting another on ignore, thereby leaving the other to "claim" a so-called victory - when in actual fact it's the forum that ends up losing).

Yea it is vast topic and I doubt we will ever even scratch the surface. For example, look at this - it is the extraction manual for rescue workers for 7 series. The top of the B pillar is deliberately made weaker so that rescue workers can cut it, cause Boron steel is too hard for normal cutters to cut it. We will never know all these intricate details. And I unfortunately don't have more time to research this just to argue with some one who does't even know something as basic as what a monocoque is.