All the golf balls were tested in the wind tunnel in the laboratory where a drag-beam dynamometer was used to measure the drag force, F D, on each golf ball. The input frequency to the wind tunnel’s synchronous motor was varied from 20 Hz to 60 Hz. A pitot-static tube was used to determine the speed of the air flowing in the wind tunnel.
Full Answer
Why do golf balls have different drag coefficients?
The current study experimentally measured drag coefficients of a range of commercially available golf balls, under a range of wind speeds. It was found that the drag coefficients of these balls varied significantly due to varied dimple geometry. …
Why do golf balls travel farther when launched from a driver?
This allowed the ball to travel farther than a smooth ball launched at the same speed and launch angle without spin. As soon as a golf ball is launched off a driver, it starts its trajectory straight down the runway (fairway) with lift forces greater than the weight of the ball and drag forces that will immediately start slowing it down.
How does the USGA measure a golf ball’s speed?
Things have changed since, and the USGA has perfected the “Indoor Test Range” (ITR) which supersedes a wind tunnel and force-balance system to measure the aerodynamic properties of a ball. The ITR is a 70-foot-long open area with a series of stations along its length. At each station, the exact ball position and speed are measured as it passed by.
What is the aerodynamics of a golf ball?
The aerodynamics of golf balls is considerably more complex than that of many other spherical balls. The surface roughness in the form of dimples intensifies the level of complexity and three-dimensionality of air flow around the golf ball.
How does a golf ball create lift?
The circular motion of a golf ball as it travels through the air. As a ball moves forward through the air, the dimples cause the ball to actually spin backwards, pulling the airflow downwards. As this happens, the air at the bottom of the ball pushes up against the ball, creating more lift.
How do you test a golf ball?
Drop Them. One of the simplest ways to check your golf ball's performance is by giving it a good, old-fashioned bounce using any hard surface like a tile floor or countertop. Your goal is to make the ball bounce as high as you can reasonably bounce it without damaging anything in your home.
Do dimples on a golf ball decrease surface drag?
First, dimples allow air to flow more smoothly around a ball's surface, which decreases the wake and low-pressure area behind the ball, resulting in less drag. Second, the dimples increase lift by causing the air to move faster at the top of the ball, creating lower pressure there.
How does drag affect a golf ball?
Most golf balls have between 300 and 500 dimples, which have an average depth of about 0.010 inch. The lift and drag forces on a golf ball are very sensitive to dimple depth: a depth change of 0.001 inch can produce a radical change to the ball's trajectory and the overall distance it can fly.
Are 20 year old golf balls still good?
The golf ball researchers at Titleist state, "Today's Titleist golf balls can be safely stored for five years or even more, as long as they are kept away from excessive heat. ... Normal indoor conditions should be fine for storage."
What swing speed is needed for Pro V1?
According to Titleist, having a swing speed of at least 105 MPH is ideal for hitting a Pro V1x well. At this speed, you'll be able to compress the ball properly, which will result in more distance and optimal height. Having the right ball for your swing speed is pretty important and it's actually a pretty common thing.
How do you reduce drag?
10 Ways to Reduce Frontal DragKeep the body aligned. ... Keep the head down. ... Pull underwater with a high elbow. ... Wear the fastest technology racing suit possible. ... Shave all the hair from your body. ... Streamline off the start and all turns for a pool swim. ... Keep your kick tight. ... Double cap.More items...
Is it better to have more or less dimples on a golf ball?
The number of golf ball dimples is less important than the shape and depth of the dimples. The number of dimples can affect drag, so it is important to not have too many dimples. Between 330 and 400 dimples is the optimum number. More dimples mean more focussed control over the ball trajectory.
Why is a golf hole 4.25 inches?
Four-and-a-quarter inches in diameter. R&A ADOPTS 4.25-INCH HOLE SIZE That first hole-cutting implement utilized a cutting tool that was, you guessed it, 4.25 inches in diameter. The folks running the R&A apparently liked that size and so adopted it in their rules for 1891.
Why is my golf ball not smooth?
"The dimples on a golf ball create a thin turbulent boundary layer of air that clings to the ball's surface. This allows the smoothly flowing air to follow the ball's surface a little farther around the back side of the ball, thereby decreasing the size of the wake.
Do dimples on a golf ball make it fly farther?
0:544:54Science of Golf: Why Golf Balls Have Dimples - YouTubeYouTubeStart of suggested clipEnd of suggested clipIt you can make golf balls go a lot farther.MoreIt you can make golf balls go a lot farther.
Do dimples on a golf ball make it go faster?
Lift generated by a dimpled ball A dimpled golf ball not only accelerates faster than a smooth one, but it can also attain more lift, provided there is significant backspin on the ball. Backspin makes the air move backwards faster on the top of the ball than at the bottom, thanks to the dimples.
Why do golfers mark their ball with Sharpie?
5:018:103 WAYS TO USE A SHARPIE AND IMPROVE YOUR GAME - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd. So the third way that you can use a sharpie to help you with your golf game is on the puttingMoreAnd. So the third way that you can use a sharpie to help you with your golf game is on the putting green now. We've all seen golfers who place a line on the golf ball with a sharpie.
Why do golfers put dots on their balls?
Marking your golf ball is a tool to ensure that you can identify your golf ball and avoid penalty strokes. It can make your alignment on the tee, fairway (when placing is allowed), and on the green much simpler.
Why do golfers draw a line on their ball?
If a golfer likes to pick a specific point to putt to — a small target six inches right and three feet short, for example — then go ahead and use a line. This allows the golfer to aim perfectly and when they are stroking the putt, they can simply attempt to control distance.
How do professionals mark their golf balls?
Dots or Personalizations Most PGA Tour pros have a stamp of their name, nickname, or initials on every golf ball (For example, Tiger uses “Tiger” … Rory McIroy uses “Rors”). You can do the same by custom ordering golf balls or simply drawing a dot or initials as well.
When did the Iron Byron launcher replace the golf ball?
Golf Ball Testing. In January 2002 , Iron Byron will be replaced by a launcher that fires a ball into a 70-foot tunnel lined with sensors (the Indoor Test Range, or ITR).
Does the USGA share its ball software?
What's more, the USGA has shared its software with ball manufacturers, which means that the manufacturers can now use this sophisticated procedure in conjunction with their own R&D efforts to design new customized balls for all kinds of different golfers.
How difficult is it to drive a golf ball?
Playing golf and “driving” a ball with some degree of proficiency is difficult, and almost as time-consuming to perfect as “driving” a plane. For one, the rules of golf do not permit “Artificial Devices and Unusual Equipment which might assist [the player] in making a stroke in his play,” which essentially means that golfers don’t get the benefit of autopilot. Second, golf requires a person to stroke an object (the ball) with another object (the club head), which is attached to the end of a 40-inch shaft (+/-5 inches). This action must be performed so precisely that the ball will fly approximately 280 yards in the air, within a horizontal window of 4 degrees from the launch pad, and stay in the fairway (short grass)…only so you can find it and repeat the process with another club, resulting in a completely different trajectory.
How does a golf ball start its trajectory?
Flight Conditions. As soon as a golf ball is launched off a driver, it starts its trajectory straight down the runway (fairway) with lift forces greater than the weight of the ball and drag forces that will immediately start slowing it down.
How fast does a smooth ball go?
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.
Why does a golf ball spin?
The reason for this is that when the golf ball passes through the air, the roughened surface creates a layer of turbulence at the surface of the ball. As it spins , the surface air is dragged around the ball, creating a profile of disturbed air similar to an airfoil. This then works the same way as a very short (front to back), stocky wing, creating the lift force which allows the ball to stay in flight for longer periods of time than a smooth ball. It is unfortunate that these same forces, which create lift, also create a hook and slice (an undesirable deviation left or right of the target) when the axis of spin is tilted to the left or right.
What are the dimples on a golf ball?
It is the dimples (surface treatment) on the golf ball that are responsible for its flight characteristics. Their design (i.e., size, shape and pattern on the surface of the ball) will help dictate the ball’s trajectory.
How does a golf ball fly?
The complex science of aerodynamics can help us understand precisely how the air flows over the surface of the ball, allowing it to fly through the air like a plane rather than take on the trajectory of a bullet. In fact, a golf ball can travel farther than any other round object of the same size and weight launched under ...
How far does a golf ball fly in the air?
This action must be performed so precisely that the ball will fly approximately 280 yards in the air, within a horizontal window of 4 degrees from the launch pad, ...
What is friction drag?
Friction drag is a nonnegligible matter when relative motion happens between solid and liquid phase, which brings many inconveniences in ship navigation, fluid transportation, microfluid devices, etc. Thereby various methods have been developed focusing on friction drag reduction. In this article, a review of several widely studied drag reduction methods is given, specially, their advantages and limitations in practical applications are discussed. Besides, a comparison of different methods is made and the development prospect of drag reduction is concluded.
How do dimples reduce drag?
With this increased turbulence, the flow reattaches to the sphere surface with a high momentum near the wall and overcomes a strong adverse pressure gradient formed in the rear sphere surface. As a result, dimples delay the main separation and reduce drag significantly. The present study suggests that generation of a separation bubble, i.e., a closed-loop streamline consisting of separation and reattachment, on a body surface is an important flow-control strategy for drag reduction on a bluff body such as the sphere and cylinder.
How does a dimple affect aerodynamics?
It has been found that by placing a dimple in an aerofoil will reduce drag at a specific AOA. This project work illustrates the change in aerodynamic characteristics of an airfoil by changing the size, shape and location of dimples in an aerofoil. By considering numerous types of dimples, alterations have been done and studied at different Angle of Attacks. Aerodynamic analysis for this airfoil is carried out using Computational Fluid Dynamics. From this investigation it has been detected that the lift force and stall Angle of Attack has been increased efficiently by simply using dimples on the aerofoil.
What are drag reduction surfaces used for?
In the past decades, drag-reduction surfaces have attracted more and more attention due to their potentiality and wide applications in various fields such as traffic, energy transportation, agriculture, textile industry, and military.
How do indented surface grooves affect wind turbines?
Indented surface grooves can eliminate the laminar separation bubbles formed on airfoil surfaces, and thus have the potential to improve the aerodynamic performance of small wind turbines. In this study, a three-equation transitional turbulence model was selected and validated with experimental data to simulate the 2D flow around a NACA 4415 airfoil. Parametric simulation of surface groove characteristics was then conducted to investigate their effects on aerodynamic behavior. It was found that the recess depth ratio (h/δ, h: groove recess depth, δ: baseline boundary layer thickness) is the key influencing factor among the groove feature parameters, with the most effective value between h/δ=1.0 and 1.5. A smaller aspect ratio of recess depth to groove width is required to trap the vortex for a shallow recess depth, while a higher aspect ratio can stabilize the vortex for a deep recess. The endpoint of a groove can affect the potential vortex size within it, and the optimum endpoint is located around 0.16c (c: airfoil chord). Moreover, a rectangular groove especially for a recess depth ratio h/δ=1.2−1.5 offers better aerodynamic performance than an arc groove, as the rectangular configuration more efficiently restricts the flow motion inside the groove.
How fast can a golf ball swing?
They can stand repeated high-speed swing speeds of up to 125mph without changing shape or deforming according to Golf Digest.
What are the main elements of a golf ball?
Golf balls have 3 main elements which matter – the cover, layers and compression – and whatever the design or make of the ball you use it will simply be a variant of a combination of these 3 main elements. Two-piece (i.e. 2 layered) ball – Most players are best to start with a two-piece ball with low compression.
What is a 3 piece golf ball?
Three-piece (i.e. 3 layered) ball – A 3-piece golf ball has a solid core which is surrounded by an outer layer and a soft cover on the outside. The additional layer and softer cover are designed to promote a greater rate of spin and allow more control over the ball for more skilled golfers. This ball type will typically be more expensive. The frequently best-rated 3-piece ball is the Titleist ProV1.
What is surface cover in golf?
The ‘surface cover’ is the element of all golf balls most susceptible to damage. Provided a ball suffers only small scuffs or paint loss it can continue to be played without any loss of performance. You might think it’s obvious whether a golf ball is still able to be used or not.
Why does water damage a golf club?
The presence of water on the clubface when you hit the ball can worsen damage to the cover. Water decreases the friction between the club and the ball, which leads to slipping and a ‘grabbing’ of the ball by the grooves on your club and therefore increased wear and tear on the ball.
What to do if it's raining on a golf course?
So if it’s raining, or the course is wet, make sure you dry the clubface with a towel before you hit your next shot. It will reduce the damage on the cover of your ball and make it last longer.
Is a golf ball resilient?
Well it turns out that the modern golf ball really is incredibly resilient.
