A few threads ago I made a comment about recent research into aerodynamics on dimpled surfaces producing less drag than smooth surfaces.
Although this research was not directed at golf ball design it prompted several remarks comparing the two.
The below is from a different source relating to golf ball dimples which should substantiate the original statement.
[Wind tunnel experiments show that the dimples on a nonspinning golf ball actually decrease the drag force, allowing the ball to slip through the air with less resistance than a smooth ball, but only at speeds between about 55 mph and 300 mph. Below 55 mph, both the smooth and dimpled balls slip through the air with about the same resistance (drag force).
It is at the critical speed of about 55 mph that the nonspinning, dimpled golf ball passes the critical "Reynolds number"(aerodynamic jargon for "force barrier"), reducing the drag force significantly. The smooth ball goes through a similar force barrier, but at a critical speed of about 300 mph, and at this speed has less drag than the dimpled ball. It is at these critical speeds that the drag tail (turbulence behind the ball) suddenly decreases in size. The separation point of air causing the turbulent tail or wake rapidly moves from a point about 80 degrees from the air flow direction to about 110 degrees around the back of the ball. This is sometimes referred to as "delayed separation" (see illustration on page 6). When this happens, the drag force decreases by almost 40% of that just prior to this critical speed.
The drag force on the golf ball will then slowly increase as the speed increases. A golf ball well-struck off a driver is launched at about 160 mph and lands at about 70 mph. Thus, the ball would be in this decreased drag zone for most of its flight, taking advantage of the phenomenon.]
If we knew the speed (Reynolds Number)at which least resistance occured on the insight it would provide another tool for obtaining max fuel efficiency.
Or could the Insight surface (skin drag) be improved with a dimpled surface ?
DGate
2000 Insight
Mini City El..Electric
87 Cit 2CV
Daihatsu K Class
Although this research was not directed at golf ball design it prompted several remarks comparing the two.
The below is from a different source relating to golf ball dimples which should substantiate the original statement.
[Wind tunnel experiments show that the dimples on a nonspinning golf ball actually decrease the drag force, allowing the ball to slip through the air with less resistance than a smooth ball, but only at speeds between about 55 mph and 300 mph. Below 55 mph, both the smooth and dimpled balls slip through the air with about the same resistance (drag force).
It is at the critical speed of about 55 mph that the nonspinning, dimpled golf ball passes the critical "Reynolds number"(aerodynamic jargon for "force barrier"), reducing the drag force significantly. The smooth ball goes through a similar force barrier, but at a critical speed of about 300 mph, and at this speed has less drag than the dimpled ball. It is at these critical speeds that the drag tail (turbulence behind the ball) suddenly decreases in size. The separation point of air causing the turbulent tail or wake rapidly moves from a point about 80 degrees from the air flow direction to about 110 degrees around the back of the ball. This is sometimes referred to as "delayed separation" (see illustration on page 6). When this happens, the drag force decreases by almost 40% of that just prior to this critical speed.
The drag force on the golf ball will then slowly increase as the speed increases. A golf ball well-struck off a driver is launched at about 160 mph and lands at about 70 mph. Thus, the ball would be in this decreased drag zone for most of its flight, taking advantage of the phenomenon.]
If we knew the speed (Reynolds Number)at which least resistance occured on the insight it would provide another tool for obtaining max fuel efficiency.
Or could the Insight surface (skin drag) be improved with a dimpled surface ?
DGate
2000 Insight
Mini City El..Electric
87 Cit 2CV
Daihatsu K Class