So, as part of the new 'Grand Prix' style cars in the Mantium Virtual Racecar Championship I created a basic car... initially just to check that the rules "worked", but also to offer as a starting point for anyone who wanted to join the championship but felt daunted by the idea of making a full car... You can download these parts here:-
(includes Heat Exchanger and carrier plate parts).
Updated front Wing
...As it turns out I don't think anyone used the car... but it was submitted as a non-points-scoring entry for the 1st race anyway.
As many may have seen on the main MVRC topic; we never intended to make the cars exactly like F1 cars... but there is clearly a resemblance there.... to make the rules and rule-checking easier we have much simpler rules... in some areas this means there are more constraints than the real F1 cars, and in others we have more freedoms... I'm pleased with the way the rules have worked out; we had some great cars submitted for the first race, with some really nice features...
...The same can't be said of my car...
It was intentionally simple; no trick features, just a simple two element front wing, a basic "traditional" shaped diffuser with no strakes, a simple floor and one barge board element. It wasn't CFD test beforehand, so I had no idea about it's aerodynamic performance.
As part of the submission to each MVRC race you get back a CFD report which includes 100's of images showing pressure plots, velocities, streamlines, etc, here's a few examples:-
There are also 5 key aerodynamic characteristics which determine each cars performance:-
Drag coefficient (x Area) = 1.03m^2
Downforce coefficient (x Area) = -1.119 m^2
Centre of Pressure = 1.91m
Sidepod Cooling Flow = 2.447m^3/sec
Air intake Pressure integral
Exhaust Outlet Pressure integral
The sidepod cooling flow was a little less than needed (3.0m^3/sec), which meant the car was down on power.. whilst it had a reasonably low drag, it also had very little downforce.... On the positive side the balance was pretty good... (optimum COP is 1.85m).
The pressure plots clearly show where the problems are;
1, The upper elements of the front wing are producing no downforce at all: essentially they are aligned with the flow coming off the lower element, and as such are not imparting any momentum change to the air flowing around them.
2, The diffuser isn't really creating much downforce; again, not surprising since the car had a gently sloped diffuser with no strakes; so there's a lot of untapped energy in the diffuser.
Clearly there are lots of other areas that could be improved too.... but for the second round I didn't want to make any drastic changes (and as a non-points-scoring entry I am not trying to win the champinship -not that I could even if I wanted; the top teams really are very good!);I just wanted to make some basic changes to see how much difference they would make.
The first thing however was to address those terrible aesthetics: a sleeker nose and more streamlined head protection... just because the original looked awful...
The basic sidepod design remained the same, but with a bigger inlet, and large heat exchangers (achieved by installing them at a flatter angle, allowing them to be 'taller')... hopefully that would address the power loss....
The front wing gets new upper elements with more curvature, and the diffuser gets a 'double-inflection' profile and a couple of basic strakes...
I'll post an update after I get the results from the second race, which will occur shortly.
The competition is still open to new competitors.... I think it's a great thing to do if you are interested in racecar aerodynamics... it would look great on your CV if you're an engineering student, it's another way to practice your CAD skills, or finally if you're a frequent forum poster explaining where the real F1 teams are going wrong, here's your chance to prove you really do know what you're talking about
Go to www.mantiumchallenge.com
for entry instructions and rules.