shelly wrote:
2 converging strakes does not mean that flow would be accelerated in between - no venturi or nozzle or funnel in my opinion.
I think we're in violent agreement here.
Even though the flow between the strakes will be very slightly accelerated at the exit but that is IMHO not the desired effect itself, it simply cannot be avoided. Upstream between the strakes the flow will be significantly slower and that is in my opinion the much more important aspect.
I think the real trick is the resulting increased static pressure between the strakes. inward of the inner strake you have low pressure caused by the fast exhaust gases. This will cause a rotating movement over the inner strake due to the pressure differential (similar to how the footplate vortex is created). This rotation will force the exhaust gases to rotate too, thereby further increasing velocity/energy and stabilising/bundling them.
The strake that has been "added" is the outer one: the inner one is similar to what other teams are running, with exhaust flowing inside of it, the outer strake pushes the flow around the inner more.
Again: We are in full agreement with the tiny exception that I think the inner strake is mounted slightly different to the regular ones in that it seems to have a slight toe- in, thereby creating more opposing force on floor level to the inward flow in front of the tyre which is directed/supported by the added outer strake.
)
