air flowing around objects in streamlines
streamlined flow is also called laminar flow
- laminar flow links
- Wikipedia link on laminar flow
- NASA link on aerodynamic drag
- Science Learning link on aerodynamic drag
- Video about streamlines from talk at Univ of Mich
- occurs when a fluid flows in parallel layers, with no disruption between the layers
- the fluid (air in this case) is comprised of an immense numbers of molecules
- the molecules are jittering back and forth colliding with themselves at 1100 miles per hour in very short distances (.000001 inches)
- air velocity (or apparent wind in the case of an iceboat) is less than 10 percent of the molecular speed
- you must consider the whole streaming flow in a realistic mathematical model of the corresponding lift and drag elements
- examine the differences between the streamlines in the top diagram where the resistance goes from 100% down to 5%
- the greater the resistance, the greater the spoiled streamlines at the rear of the wing
- the roiled air is caused by flow separation of the streamline
- flow separation happens when the flow streamline exceeds a large curvature within a short distance
- the more you can reduce of eliminate the eddies (i.e. roiled or turbulent air flow), the better will be the performance
