[MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post here information about your own engineering projects, including but not limited to building your own car or designing a virtual car through CAD.
User avatar
LVDH
44
Joined: 31 Mar 2015, 14:23

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

JJR wrote:
21 Nov 2019, 09:46
Currently I ´m trying to reproduce F1 car from early 90 ´s and see how it compare to our cars. I will try post results next week.
That is awesome. My preference for our F1 rules would be these old 90s cars. However Richard convinced me that it would actually not be possible. The cars at the time did not look the way they looked because of rules but more because of manufacturing constraints, so replicating that would require very artificial rules. So if your create such a car you would make me super happy.

User avatar
maunde
2
Joined: 02 Nov 2019, 12:36

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

Hello everyone, I'd like to ask a question regarding the performance calculation of the competition. The time calculator on the MVRC website takes a singular COP - how is this calculated for each stage of the simulation?

What flow conditions are used to determine the COP and other aspects of the aero performance for a given track? Is a 'full' aero map created?

Thanks in advance,
Maunde
A kiwi looking to fly like McLaren.

User avatar
CAEdevice
47
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

LVDH wrote:
21 Nov 2019, 09:58
JJR wrote:
21 Nov 2019, 09:46
Currently I ´m trying to reproduce F1 car from early 90 ´s and see how it compare to our cars. I will try post results next week.
That is awesome. My preference for our F1 rules would be these old 90s cars. However Richard convinced me that it would actually not be possible. The cars at the time did not look the way they looked because of rules but more because of manufacturing constraints, so replicating that would require very artificial rules. So if your create such a car you would make me super happy.
I agree with Richard: old 90s rules applied in a competition would lead not lead to 90s cars, but to new and not realistic beasts. On the contrary, the study JJR is doing to compare 90s and todays car shape is very interesting.

User avatar
CAEdevice
47
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

maunde wrote:
21 Nov 2019, 10:18
Hello everyone, I'd like to ask a question regarding the performance calculation of the competition. The time calculator on the MVRC website takes a singular COP - how is this calculated for each stage of the simulation?

What flow conditions are used to determine the COP and other aspects of the aero performance for a given track? Is a 'full' aero map created?

Thanks in advance,
Maunde
COP depends on the cars not on the track. The optimum value with our laptime physics (but the realty is very near) is when COP corresponds to COM (center of mass), that is established by the rules (1,85m from the front wheels axle).

User avatar
CAEdevice
47
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

Let's go on with the sexy striptease of our cars.

This time I am trying to explain the reason for the hole that connects the upper part of the bottom with the diffuser. The mechanism is the reverse of the "double diffuser" because air is added (and not removed) from inside the diffuser. The intent is to clean the turbulent flow (due to a too abrupt transition imposed by the rules). The mechanism is similar to that of the tangential flow that passes from the high pressure zone to the low pressure zone of ​​a wing profile composed of several airfoils (see Koldskaal and Variante posts above).

The gain is small, but it can help: Cl*A + 3% Cd*A - 1%.

With the layout of my cooling system there is also a very small but welcome increase in flow, because the diffuser sucks air in the air outlet area.

Image

User avatar
maunde
2
Joined: 02 Nov 2019, 12:36

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

CAEdevice wrote:
21 Nov 2019, 10:48
maunde wrote:
21 Nov 2019, 10:18
Hello everyone, I'd like to ask a question regarding the performance calculation of the competition. The time calculator on the MVRC website takes a singular COP - how is this calculated for each stage of the simulation?

What flow conditions are used to determine the COP and other aspects of the aero performance for a given track? Is a 'full' aero map created?

Thanks in advance,
Maunde
COP depends on the cars not on the track. The optimum value with our laptime physics (but the realty is very near) is when COP corresponds to COM (center of mass), that is established by the rules (1,85m from the front wheels axle).
So, at which flow rate is the COP calculated? Are the flow conditions at which it is calculated dependant on the Mantium software?
A kiwi looking to fly like McLaren.

User avatar
CAEdevice
47
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

maunde wrote:
21 Nov 2019, 11:08
CAEdevice wrote:
21 Nov 2019, 10:48
maunde wrote:
21 Nov 2019, 10:18
Hello everyone, I'd like to ask a question regarding the performance calculation of the competition. The time calculator on the MVRC website takes a singular COP - how is this calculated for each stage of the simulation?

What flow conditions are used to determine the COP and other aspects of the aero performance for a given track? Is a 'full' aero map created?

Thanks in advance,
Maunde
COP depends on the cars not on the track. The optimum value with our laptime physics (but the realty is very near) is when COP corresponds to COM (center of mass), that is established by the rules (1,85m from the front wheels axle).
So, at which flow rate is the COP calculated? Are the flow conditions at which it is calculated dependant on the Mantium software?
When the CFD challenges began, they used to compute Cd, Cl and CoP with different speeds, but after a while it was clear that in the range of the speed actually measuered on the track all these coefficients change in a negligible way depending on speed.

I think that MVRC speed parameter is arond 40-50m/s, you can find the exact value in the rulebook and in the OpenFOAM folder created by MFlow.

User avatar
maunde
2
Joined: 02 Nov 2019, 12:36

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

CAEdevice wrote:
21 Nov 2019, 11:13
maunde wrote:
21 Nov 2019, 11:08
CAEdevice wrote:
21 Nov 2019, 10:48


COP depends on the cars not on the track. The optimum value with our laptime physics (but the realty is very near) is when COP corresponds to COM (center of mass), that is established by the rules (1,85m from the front wheels axle).
So, at which flow rate is the COP calculated? Are the flow conditions at which it is calculated dependant on the Mantium software?
When the CFD challenges began, they used to compute Cd, Cl and CoP with different speeds, but after a while it was clear that in the range of the speed actually measuered on the track all these coefficients change in a negligible way depending on speed.

I think that MVRC speed parameter is arond 40-50m/s, you can find the exact value in the rulebook and in the OpenFOAM folder created by MFlow.
Fascinating, I'm glad it simplifies things quite a lot. However, if this is the case, how are they determining what is a more optimal car for a certain track?

Are they giving each input parameter to the track timer a certain weighted value to calculate a time for a given car? Then they change different weights for different tracks so that they each require different parameters/'types' of cars?

Thanks for the response!
A kiwi looking to fly like McLaren.

User avatar
CAEdevice
47
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

maunde wrote:
21 Nov 2019, 11:19
CAEdevice wrote:
21 Nov 2019, 11:13
maunde wrote:
21 Nov 2019, 11:08


So, at which flow rate is the COP calculated? Are the flow conditions at which it is calculated dependant on the Mantium software?
When the CFD challenges began, they used to compute Cd, Cl and CoP with different speeds, but after a while it was clear that in the range of the speed actually measuered on the track all these coefficients change in a negligible way depending on speed.

I think that MVRC speed parameter is arond 40-50m/s, you can find the exact value in the rulebook and in the OpenFOAM folder created by MFlow.
Fascinating, I'm glad it simplifies things quite a lot. However, if this is the case, how are they determining what is a more optimal car for a certain track?

Are they giving each input parameter to the track timer a certain weighted value to calculate a time for a given car? Then they change different weights for different tracks so that they each require different parameters/'types' of cars?

Thanks for the response!
Machin will give you a more accurate answer, but generally speaking, in our "ideal" world, the best option is to have COP and COM in the same point.

Weight and weight distribution are always the same, this is a aerodynamics competition so mechanical properties do not change between tracks.

User avatar
maunde
2
Joined: 02 Nov 2019, 12:36

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

CAEdevice wrote:
21 Nov 2019, 11:23
maunde wrote:
21 Nov 2019, 11:19
CAEdevice wrote:
21 Nov 2019, 11:13


When the CFD challenges began, they used to compute Cd, Cl and CoP with different speeds, but after a while it was clear that in the range of the speed actually measuered on the track all these coefficients change in a negligible way depending on speed.

I think that MVRC speed parameter is arond 40-50m/s, you can find the exact value in the rulebook and in the OpenFOAM folder created by MFlow.
Fascinating, I'm glad it simplifies things quite a lot. However, if this is the case, how are they determining what is a more optimal car for a certain track?

Are they giving each input parameter to the track timer a certain weighted value to calculate a time for a given car? Then they change different weights for different tracks so that they each require different parameters/'types' of cars?

Thanks for the response!
Machin will give you a more accurate answer, but generally speaking, in our "ideal" world, the best option is to have COP and COM in the same point.

Weight and weight distribution are always the same, this is a aerodynamics competition so mechanical properties do not change between tracks.
Are the track characteristics determined at the start of the year and kept the same (all tracks are given a specific set of characteristics)?

While I fully trust that the Mantium crew will not alter the rules to intentionally affect competitors, a change in characteristics of a future track part way through the season could affect one competitor more than the other. As I said, I'm sure this won't happen intentionally, but bias could affect it.

Cheers
A kiwi looking to fly like McLaren.

User avatar
CAEdevice
47
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

maunde wrote:
21 Nov 2019, 11:31
CAEdevice wrote:
21 Nov 2019, 11:23
maunde wrote:
21 Nov 2019, 11:19


Fascinating, I'm glad it simplifies things quite a lot. However, if this is the case, how are they determining what is a more optimal car for a certain track?

Are they giving each input parameter to the track timer a certain weighted value to calculate a time for a given car? Then they change different weights for different tracks so that they each require different parameters/'types' of cars?

Thanks for the response!
Machin will give you a more accurate answer, but generally speaking, in our "ideal" world, the best option is to have COP and COM in the same point.

Weight and weight distribution are always the same, this is a aerodynamics competition so mechanical properties do not change between tracks.
Are the track characteristics determined at the start of the year and kept the same (all tracks are given a specific set of characteristics)?

While I fully trust that the Mantium crew will not alter the rules to intentionally affect competitors, a change in characteristics of a future track part way through the season could affect one competitor more than the other. As I said, I'm sure this won't happen intentionally, but bias could affect it.

Cheers
Mechanical properties of the cars are the same during all season!
You can verify it from the files in the load case folder created by MFlow.

The tracks simulaton are revealed during season, but in (large) advance from the date of the submission.

Don't think too much about this kind of problems: this year I started making tests with specific tracks after the third race... before I was to busy in understanding my own car!

User avatar
maunde
2
Joined: 02 Nov 2019, 12:36

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

CAEdevice wrote:
21 Nov 2019, 11:39
maunde wrote:
21 Nov 2019, 11:31
CAEdevice wrote:
21 Nov 2019, 11:23


Machin will give you a more accurate answer, but generally speaking, in our "ideal" world, the best option is to have COP and COM in the same point.

Weight and weight distribution are always the same, this is a aerodynamics competition so mechanical properties do not change between tracks.
Are the track characteristics determined at the start of the year and kept the same (all tracks are given a specific set of characteristics)?

While I fully trust that the Mantium crew will not alter the rules to intentionally affect competitors, a change in characteristics of a future track part way through the season could affect one competitor more than the other. As I said, I'm sure this won't happen intentionally, but bias could affect it.

Cheers
Mechanical properties of the cars are the same during all season!
You can verify it from the files in the load case folder created by MFlow.

The tracks simulaton are revealed during season, but in (large) advance from the date of the submission.

Don't think too much about this kind of problems: this year I started making tests with specific tracks after the third race... before I was to busy in understanding my own car!
Sure, this makes sense. In general then, a car will do better with max L/D and COP nearest (and slightly behind) COG ?

Is there a list of competitor's coefficients vs placing per race?

Cheers
A kiwi looking to fly like McLaren.

User avatar
CAEdevice
47
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

maunde wrote:
21 Nov 2019, 11:43
CAEdevice wrote:
21 Nov 2019, 11:39
maunde wrote:
21 Nov 2019, 11:31


Are the track characteristics determined at the start of the year and kept the same (all tracks are given a specific set of characteristics)?

While I fully trust that the Mantium crew will not alter the rules to intentionally affect competitors, a change in characteristics of a future track part way through the season could affect one competitor more than the other. As I said, I'm sure this won't happen intentionally, but bias could affect it.

Cheers
Mechanical properties of the cars are the same during all season!
You can verify it from the files in the load case folder created by MFlow.

The tracks simulaton are revealed during season, but in (large) advance from the date of the submission.

Don't think too much about this kind of problems: this year I started making tests with specific tracks after the third race... before I was to busy in understanding my own car!
Sure, this makes sense. In general then, a car will do better with max L/D and COP nearest (and slightly behind) COG ?

Is there a list of competitor's coefficients vs placing per race?

Cheers
In depends on the tracks and on the general layout: this year (F1 style) in my opinion cars with high DF where preferable but my approach is to design the most efficient car I can and then to look for DF. In the LMPx years the covered wheels layout allowed for more competitive design based on efficiency.

You can test your cars on the virtal track here:

http://www.competition-car-engineering. ... Timing.htm

(You can find this link in the rulebooks)

User avatar
maunde
2
Joined: 02 Nov 2019, 12:36

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

CAEdevice wrote:
21 Nov 2019, 11:49
maunde wrote:
21 Nov 2019, 11:43
CAEdevice wrote:
21 Nov 2019, 11:39


Mechanical properties of the cars are the same during all season!
You can verify it from the files in the load case folder created by MFlow.

The tracks simulaton are revealed during season, but in (large) advance from the date of the submission.

Don't think too much about this kind of problems: this year I started making tests with specific tracks after the third race... before I was to busy in understanding my own car!
Sure, this makes sense. In general then, a car will do better with max L/D and COP nearest (and slightly behind) COG ?

Is there a list of competitor's coefficients vs placing per race?

Cheers
In depends on the tracks and on the general layout: this year (F1 style) in my opinion cars with high DF where preferable but my approach is to design the most efficient car I can and then to look for DF. In the LMPx years the covered wheels layout allowed for more competitive design based on efficiency.

You can test your cars on the virtal track here:

http://www.competition-car-engineering. ... Timing.htm

(You can find this link in the rulebooks)
Thanks for (continuously) replying :)

If next year were to be GP style, would it be appropriate to assume that an identical car would get an identical time on the same track (2020 vs 2019)? Unless of course the track had a 'modified' layout :lol:
A kiwi looking to fly like McLaren.

UlleGulle
UlleGulle
1
Joined: 26 Apr 2014, 00:31

Re: [MVRC] Mantium Virtual Racecar Challenge 2019 (Grand Prix Cars)

Post

LVDH wrote:
21 Nov 2019, 09:58
JJR wrote:
21 Nov 2019, 09:46
Currently I ´m trying to reproduce F1 car from early 90 ´s and see how it compare to our cars. I will try post results next week.
That is awesome. My preference for our F1 rules would be these old 90s cars. However Richard convinced me that it would actually not be possible. The cars at the time did not look the way they looked because of rules but more because of manufacturing constraints, so replicating that would require very artificial rules. So if your create such a car you would make me super happy.
It would be interesting, as a theoretical exercise though, to see what a modern car built to those regulations would look like. Would it be wings everywhere, or a cleaner car? Would they run it super low, or high? Would rake be introduced?