My car will suck. Literally. Vacuum Cleaner (floor air guide) mod
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Originally Posted by Mitsubishi Technical Paper 20E.pdf
The under floor air guide which effectively reduces lift has been newly developed as an optional part for the LANCER EVOLUTION X (Fig. 8). This device is the fins installed under the floor to diffuse the airflow from the underfloor to the outside of the body, thus increasing the flow velocity at the center section of the underfloor. This high velocity airflow and the vortices created the lower pressure region at the under floor behind the fins and this area contributes to reduce the lift of the body. Fig. 9 shows the results of a model test performed with a pair of air guides installed on a flat plate simulating an under floor of the vehicle. The top half of the figure shows the change in the surface pressure when the air guides are installed. The blue area indicates the region in which the pressure falls (reducing lift), and the red area indicates the region where the pressure rises.
These results reveal that the maximum pressure reduction occurs downstream of the air guide, and also that pressure is reduced even at the center of the body between the left and right air guides. Although there is a red region where the pressure rises upstream of the guides, it is smaller in area than the blue region where the pressure falls. The bottom half of the figure shows the results of a flow visualization test of the under floor using tuft method. It can be seen that the flow is diffused to the outside of the vehicle and vortices are created behind the air guides. The flow at the center part of the vehicle is thought to be drawn toward the outer part by the negative pressure of these vortices, that accelerate the flow velocity at the center part and thus reducing pressure of the under floor. Fig. 10 shows the pressure distribution obtained by CFD analysis performed both with and without the air guides on an actual under floor model. The image also shows that the air guides have increased the area of the negative pressure region (blue area). A lift reduction device represented by a front air dam and a rear spoiler are normally effective in reducing the lift at the front or the rear alone. The remarkable feature of the new air guide is that it reduces both the front and rear lift in a well-balanced manner depending on where it is installed (Fig. 11). In the LANCER EVOLUTION X, the air guide was set in the optimum position in consideration of the balance between the front and rear lift of the standard model
These results reveal that the maximum pressure reduction occurs downstream of the air guide, and also that pressure is reduced even at the center of the body between the left and right air guides. Although there is a red region where the pressure rises upstream of the guides, it is smaller in area than the blue region where the pressure falls. The bottom half of the figure shows the results of a flow visualization test of the under floor using tuft method. It can be seen that the flow is diffused to the outside of the vehicle and vortices are created behind the air guides. The flow at the center part of the vehicle is thought to be drawn toward the outer part by the negative pressure of these vortices, that accelerate the flow velocity at the center part and thus reducing pressure of the under floor. Fig. 10 shows the pressure distribution obtained by CFD analysis performed both with and without the air guides on an actual under floor model. The image also shows that the air guides have increased the area of the negative pressure region (blue area). A lift reduction device represented by a front air dam and a rear spoiler are normally effective in reducing the lift at the front or the rear alone. The remarkable feature of the new air guide is that it reduces both the front and rear lift in a well-balanced manner depending on where it is installed (Fig. 11). In the LANCER EVOLUTION X, the air guide was set in the optimum position in consideration of the balance between the front and rear lift of the standard model
I traded my friend that works at Mitsu USA Corporate a personal mini giraffe
yes / yes
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