Simulation of Aerodynamics of the Cricket Ball with Soil Conditions of the Pitch
This paper describes Simulation of Aerodynamics of the Cricket Ball using digitalanlyzer version1.2 .The results show the deviation of ball depend on aerodynamics properties. This paper also shows that different types of ball have different observed co efficient with different types of surface. This paper will help for referring decision to third umpire in LBW.
Aerodynamics of a cricket ball
Abstract This paper describes experiments performed on stationary and rotating cricket balls to determine the aerodynamic forces acting on the ball over a range of bowling speeds and seam angles. Lift, drag and side forces were measured directly and it was found they exhibited magnitudes in the order of 1.4, 1 and 0.4 N, respectively, for the stationary ball. At air velocities above 20 m/s, the lift force increased with increasing air speed being weakly influenced by the vertical seam angle. At 10 m/s air speed, the side force began to increase steadily with air speed for seam angles up to 70°. At 80° the side force direction reversed due to the sudden movement of the separation point on the surface of the ball. Roughening one side of the ball increased the side force but delayed its reversal at 80° seam angle until a marginally higher velocity was reached. When top spin was applied to the smooth ball, the lift force increased almost linearly in the negative direction but there was no resultant side force. When a roughened ball was spun, the negative lift force was constant at all air speeds over a range of rotational speeds. The development of the measured forces are discussed in terms of boundary layer flow and Magnus effect.
The Aerodynamics of Golf Balls
The aerodynamic forces on golf balls were studied by dropping spinning balls through the horizontal wind stream of the B. F. Goodrich wind tunnel. The lift, L, and drag, D, were calculated from the drift of the balls, rotating at speeds, N, up to 8000 r.p.m. while falling through a wind stream having a velocity of 105 feet per second. For a standard dimple or mesh golf ball weighing 0.1 lb., the lift varied with the rotational speed as L=0.064 ×[1−exp(−0.00026N)], with a maximum observed value of 0.055 lb. or more than half the weight of the ball. The drag increased nearly linearly from about 0.06 lb. for no spin to about 0.1 lb. at 8000 r.p.m.For a smooth ball the lift was negative at all rotational speeds below 5000 r.p.m. Above this speed, the lift was positive but was less than for the standard ball. The drag for these balls was nearly constant at about 0.08 lb. Balls with shallower dimples than standard gave intermediate results. Driving tests were consistent with the wind tunnel results.These result...