Air drag testing with a nose

Since aerodynamics is an area where we dont bump into too often in our everyday life, it must be visualized by testing. Nose down, wide body, body height from the ground etc. all that has a meaning, so best thing is to test their influence and cut off the wings from guessing.
Here I made a study of nose behaviour in air drag. Model is very simple streamline object with ability to easy transformation of it's shape, specially it's height. You can see the model in here.



I tried to simulate what is the effect of the nose height in this model. Since my previous testing with some other models, small changes did not have effect too much to dramatically change the overall drag. Altering the nose height had very little effect to the rest of the model. So It is obvious that the nose itself did do most of the results and it's variations. Tests were made with full 3D part, with full 3D simulations, and artificial ground plane was present. Results here can be seen only in 2D for clarity.

Lets start with the lowest possible height. Without changing the lenght but changing the nose height, we can see steep attack angle in the nose area, specially in the upper part of the nose. More angle you have, more it looks like a flat area to the air causing air pressure to increase. Low nose caused very little of pressure under the body, but increased the nose pressure, so things are not in balance. We could keep the nose down and make that slope less steep by lenghtening the nose, or lowering the object, but since room is required for legs to pedal, that is impossible, and lenghtening would increase the surface area, and we dont want to do that either.



So we make the nose little higher. In this model the slope is divided into half, upper and lower portion are nearly in equal angle and the air cuts into half. Pressure area is the smallest and so is the drag. pressure under the body is moderate, and things looks like more balanced. Slightly more optimized shape in this part could give little more better results.



Third model is with high nose, the slope has moved to the bottom and forces air beneath the model. Increased pressure area and increased drag is present.



Now to the results, speed of the object is 20m/s. Lowest drag was present with the 2nd model, highest drag was with the 1st model, and after a certain point while lifting the nose, drag started to increase again. So with this model, the best place was when top and the bottom slopes were equal and drag increased when slopes were unequal.
Results with numbers, smaller number represents lower drag force in Newtons.

model drag nose height
-----------------------------------
1st 0,94299593 low
2nd 0,772091841 medium
3rd 0,838201198 high


Same object was used in the next study. Does a wheel in front change the previous results? This study shows that it did not. Results are in same direction as in previous one but naturally slightly bigger drag numbers.

Results with numbers, smaller number represents lower drag force in Newtons.

model drag nose height
-----------------------------------
1st 1,281011473 low
2nd 0,989317474 medium
3rd 1,033435136 high