The type of turbulence and aerodynamic forces created in this area are complex. Aerodynamics of a golf ball with grooves jooha kim. The nodimple balls were supplied by the usga, which uses them at its research and test center in far hills, nj. Pdf aerodynamics of golf balls in still air semantic scholar. The present results are shown to capture the complex fluid dynamics inside the dimples which lead to drag reduction versus a smooth sphere, and compare well to previous experimental and computational studies.
Simulates backspin on golf ball or topspin on tennis ball for uniform ball, symmetry guarantees lift force normal to both vectors actual trajectories involve arbitrary orientation of. This camera records thousands of images per minute. Fulltext pdf the aerodynamics of golf balls is considerably more complex than that of many other spherical balls. The aerodynamics of golf balls is considerably more complex than that of many other spherical balls. Speed sensors measured the speed and location of the balls at three locations from which the coefficient of lift and drag were found. Greater range occurs without the influence of aerodynamic forces.
It was found that the drag coefficients of these balls. Hence, the drag on a sphere is dominated by the separation on the rear face. Sep 19, 2005 how do dimples in golf balls affect their flight. Subic school of aerospace, mechanical and manufacturing engineering rmit university, melbourne, victoria 3083, australia abstract the aerodynamic behaviour of the golf ball is primarily dependent on the physical features of complex dimples. The balls travelled at speeds ranging from 18 ms to 91 ms and spin ranging from 1500 rpm to 4500 rpm. Best golf balls for the money 2017 there are many golf ball producers, and many variations of golf balls on the market, each promising new and great levels of performance. The dimples make the boundary layer more turbulent, which keeps it wrapped continue reading dimples on golf ball aerodynamics. The aerodynamics of golf balls is still not well understood, primarily because the aerodynamic performance of the golf ball depends crucially on the details of the airflow over the ball, and those details are controlled by many factors. Aerodynamic definition ultimate guide to all things aero. A study of dimple characteristics on golf ball drag.
The drag force on the golf ball will then slowly increase as the speed increases. Oct 01, 2009 a golf ball is a bluff body and most of the drag is due to airflow separationthe flow cannot close behind the ball and stay attached, says steve ogg, vice president of golf ball research and. Experiments have been done on the shape, size, depth, and number of the dimples on a golf ball. For a standard dimple or mesh golf ball weighing 0. A golf ball wellstruck off a driver is launched at about 160 mph and lands at about 70 mph. Building a better golf ball the ben hogan company used nasa technology. Pdf a study of golf ball aerodynamic drag tom steiner. This question was originally answered on quora by kim aaron. The present results are shown to capture the complex fluid dynamics inside the dimples which lead to drag reduction versus a smooth sphere, and compare well to previous experimental and computational. The exact details are fairly complex and are given on a separate slide. The current study experimentally measured drag coefficients of a range of commercially available golf balls, under a range of wind speeds.
Who benefits the most from aerodynamic gear might surprise you. If we could minimize that, the drag would be reduced. The dimples vary in sizes, shapes and depths which generate complex aerodynamic flow. For our experiment, the students noted that the independent variable was the type of ball with dimples or without. The airfoil of a wing turns a flow, but so does a spinning ball. Youre standing in the pro shop, its 10 minutes to tee off time and you are short on balls for the round again. This paper presents the first highorder computational fluid dynamics cfd simulations of static and spinning golf balls at realistic flow conditions. If a golf ball with backspin causes the air on top of it. The aerodynamic of golf ball is still not fully understood in spite of a significant number of published data in the open literature. Jun 06, 2018 drag across a golf ball can affect distance traveled when hitting a ball. Highorder computational fluid dynamics simulations of a. A study of golf ball aerodynamic drag sciencedirect. Details of these three balls, together with typical operating conditions, are given in figure 1. In this study, we investigate the aerodynamics of our newly designed golf ball that does not have dimples but grooves on its surface.
Jan 30, 2017 i have no idea why a car with dimples got better gas mileage than without. Subic school of aerospace, mechanical and manufacturing engineering rmit university, melbourne, victoria 3083, australia abstract the aerodynamic behaviour of the golf ball is primarily. Golf ball aerodynamics fluid mechanics aerodynamic basics the origins of drag move any object through the air, and youll get some drag. Dimples on golf ball aerodynamics site for golfers. Thus, the ball would be in this decreased drag zone for most of its flight, taking advantage of the phenomenon. Golf ball aerodynamics bearing motor figure 3 ball model outer shell supporting wire 2.
Most flying bodies not including the occasional golf club have a streamlined profile by design or by nature, so that they cut through the air cleanly with minimal drag. Boeing used aerodynamics to build a better golf club. If dimples reduce drag, why dont we see this surface feature on other aerodynamic shapes like airplane wings. The physics of golf aerodynamics of ball flight the dimples on a golf ball create a thin turbulent boundary layer of air over the balls surface.
The golf ball is actually the only equipment that golfers use every stroke. The bridge golf learning center provides feebased services for golfers of all skill levels and ages. Two important factors in the balls trajectory are the. The ultra registered trademark 500 series golf ball above, introduced in 1995 by wilson sporting goods company, humboldt, tennessee, has 500 dimples arranged in a pattern of 60 spherical triangles.
The dimpled golf ball was rst introduce in 1905 by wiliam taylor, an engineer. Drag has significant effect in reducing the range and lift modifies the trajectory shape taken from wesson, 2009. Some have even compared the airflow surrounding a spinning golf ball to the dynamic reaction of two wing tips meeting. A wind tunnel technique has been developed to measure the aerodynamic forces acting on golf balls over a wide range of reynolds number and spin rate. Proceedings free fulltext aerodynamics of golf balls. Golf ball has dimples on its surface because we want a turbulent boundary layer. Smith understanding the aerodynamic properties of the ball can lead to better predicting the path of a ball. Summarizing the results, the amount of force generated by a spinning ball depends on the amount of spin, the velocity of the ball, the size of the ball, and the density of the fluid. Does this mean that a golf ball is in part more complex aerodynamically than the falcon 7x, boeing 777, or even the concorde. Activities the four activities in this toolkit can each be done independently, but they also build on each other. Why do you think the usga regulates golf ball design. A golf ball, for example, is dimpled for a very important aerodynamic reason.
This research found that a significantly deeper dimple pattern will greatly affect the boundary layer, thus changing the drag coefficient and boundary layer. Aerodynamics of golf balls physics sport sports golf. Find out moreread key concepts at the back of this toolkit. Drag across a golf ball can affect distance traveled when hitting a ball. That probably has little meaning unless you are a golf pro or a low handicap amateur, but the design represents a major. The lift, l, and drag, d, were calculated from the drift of the balls, rotating at speeds, n, up to 8000 r. The following considers lift and drag measurements of production golf ball models propelled through still air in a laboratory setting. Even the nongolfers of the world are familiar with the shape of a golf ball, like that pictured below, and have probably wondered why its surface is covered with small indentations called dimples.
It is known goldstein5 and achenbach6 that the flow about a smooth sphere is. Considering how aerodynamic its design is, why is it that car manufacturers dont dimple their cars like a golf ball. Science of golf series for aerodynamics, the related video is evolution of the golf ball. Golf ball aerodynamics volume 27 issue 2 p w bearman, j k harvey. That probably has little meaning unless you are a golf pro or a low handicap amateur, but the design represents a major departure from. Pdf a study of golf ball aerodynamic drag researchgate. This paper investigates the effect of dimple patterns on the boundary layer around a ball.
A whollyowned forprofit subsidiary of the bridge golf foundation, our center in harlem is committed to making golf more accessible and affordable for all people. This reduces air resistance which results in the ball traveling a farther distance than a smooth ball would. Pdf an experimental study of golf ball aerodynamics. Golf ball aerodynamics fluid mechanics further education. Jan 14, 2016 how boeing used airplane aerodynamics to build a better golf club. Dimpling makes golf balls more aerodynamic, and it. A method for determining the lift and drag coefficients of a golf ball includes launching the ball along a flight path, measuring the velocity at two positions along the flight path, using the measured velocities to determine the coefficients of lift and drag. Apr 28, 2004 the aerodynamic forces on golf balls were studied by dropping spinning balls through the horizontal wind stream of the b. Golf aerodynamics he ultraa 500 series 1 i golf ball right, intro duced in 1995 by wil son sporting goods company, humboldt, ten nessee, has 500 dimples arranged in a pattern of 60 spherical triangles.
Feb 07, 2011 how golf ball aerodynamics work golfscreener. Last week at dunwoodie golf course, we compared the flight of completely smooth golf balls to normal balls with dimples. A golf ball is a bluff body and most of the drag is due to airflow separationthe flow cannot close behind the ball and stay attached, says steve ogg, vice president of golf ball. Pdf a study of golf ball aerodynamic drag tom steiner academia. This paper investigates the effect of dimple patterns on\ the boundary layer around a ball. They had already experimented with a variety of ball designs in their golf ball division. This effect is due to the spin of the ball and explained by the magnus effect included in aerodynamics of flight. The effect of drag and lift on golf ball trajectories. The surface roughness in the form of dimples intensifies the level of complexity and threedimensionality of air flow around the golf ball. The number of dimples on a typical golf ball ranges from 250450.
Prior studies have revealed that golf ball aerodynamics is still not fully understood due to the varied dimple size, shape, depth and pattern. An average golf ball will have a drag coefficient of, 0. Before explaining the purpose of dimples, we first need to understand the aerodynamic properties of a sphere. All that is necessary to create lift is to turn a flow of air. Understanding the golf ball compression chart get in the. The aerodynamic behaviour of the golf ball is primarily dependent on the physical features of complex dimples. Pdf aerodynamics of golf balls in still air semantic. It is of importance that you have a golf ball that fits your swing and the goal of this article is to guide you to the golfball that suits your game and a golf ball that suits your level of difficulty to get the most out of the game. But, they were not sure of exactly what gave the ball its best flight. While few among us can deny that golf is one of the least exciting of all spectator sports, we aerospace engineers are fascinated by its aerodynamics. Most of the scientific work on sports ball aerodynamics has been experimental in nature and has concentrated on three sports balls. Aerodynamics of a golf ball aerodynamics science fair. A golf ball is a special ball designed to be used in the game of golf under the rules of golf, a golf ball has a mass no more than 1. The aerodynamic forces on golf balls were studied by dropping spinning balls through the horizontal wind stream of the b.
Dimples on the golf ball have significant effect on its aerodynamic properties as well as the flight trajectory. Aerodynamics of a golf ball aerodynamics science fair projects, hydrdynamics model experiments for cbse isc stream students and for kids in middle school, elementary school for class 5th grade, 6th, 7th, 8th, 9th 10th, 11th, 12th grade. Faster swings translate into more force and a golf ball that. I know why dimples reduce drag on a golf ball, and that particular set of quirky circumstances does not apply to a car.
48 709 917 645 101 1572 1661 282 228 996 516 1328 1182 1458 1247 1299 457 891 1420 1457 1064 1210 41 1200 804 154 105 807 99 299 1000 855 737 483 653 1103 936 1053 802 170 933 611 345 910 1108 14