Fast movement of the body is key here. To deal with reverse-swing, the batsman need to keep the bat down and not have a high back-lift. Also, a batsman should play the ball late is order to tackle the late movement. Experts also say the feet movement of the batsman should be top class to tackle reverse-swing. There is no doubt that reverse swing was born in Pakistan. Salim Mir, a pacer at the domestic level in Pakistan, used reverse swing in the matches. He later taught it to Pakistan pacer Sarfraz Nawaz, who used it at the Test level.
He later passed on the knowledge of reverse-swing to Imran Khan. And then came the duo of Wasim Akran and Waqar Younis who used reverse-swing to devastating effect. Once we have a overs old ball, it can be prepared to reverse swing.
It must be kept shiny on one side and rough on the other. The rough side should not be repaired and the shiny side must be properly shone by the players. The subcontinent pitches, which are dry and rough are considered to the best for reverse swing as the ball gets worn up quickly on a rough and dry pitch.
Click here to join our channel indianexpress and stay updated with the latest headlines. After a extended period of bowling, when you look at the ball, you will notice a rougher and shiny side, now the ball starts to swing in unconventional way.
Under a normal condition when the seam is towards the slip, then it is a outswinger, but in reverse swing it becomes inswinger, because of the airflow difference between the rough and shiny side. You could watch this video for further explanation. If the pitch is dry then the ball becomes rough in a small amount of time sub continent pitches.
From the science perspective, it's the Magnus effect that causes the reverse swing, You have a ball with two layers a rough and a shiny one, try passing smoke onto two sides of ball,you will see that rough side produce turbulent flow, the shiny side produce laminar flow, this creates a pressure difference Bernoulli effect and makes the ball go the other direction than the batsman anticipated.
Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?
Learn more. What is the science behind reverse swing? Ask Question. Asked 3 years, 10 months ago. Active 3 years, 10 months ago. Viewed 8k times. Improve this question. Ram Chandra Giri 6, 3 3 gold badges 18 18 silver badges 61 61 bronze badges. Neil Meyer Neil Meyer 1 1 gold badge 6 6 silver badges 15 15 bronze badges.
Add a comment. Active Oldest Votes. The simplest explanation from former England bowling coach Troy Cooley is: "Reverse swing is all to do with the deterioration of the ball and the seam position in flight. Improve this answer. If the pitch is dry then the ball becomes rough in a small amount of time sub continent pitches Seam position and the angle also plays an important role in reverse swing From the science perspective, it's the Magnus effect that causes the reverse swing, You have a ball with two layers a rough and a shiny one, try passing smoke onto two sides of ball,you will see that rough side produce turbulent flow, the shiny side produce laminar flow, this creates a pressure difference Bernoulli effect and makes the ball go the other direction than the batsman anticipated.
Similarly, an inswing bowler will suddenly be able to bowl outswingers. For a classic exposition of reverse swing, check out the third Test of the Ashes - Andrew Flintoff to Simon Katich in the second innings. One of the reasons why reverse swing has gained such notoriety is its constant link to accusations of ball-tampering, as we witnessed at The Oval in Once bowlers realised the importance of the rough surface, they started to help the process along.
They showed me several balls that had been confiscated after the umpires suspected the fielding side of ball-tampering. From what I saw, the most popular forms of tampering consisted of gouging the surface using foreign objects such as bottle tops and attempting to open up the quarter seam using fingernails.
Perhaps what is not that well-known is the fact that positive roughness can work just as well. So if some dirt was stuck to the ball's surface using sweat or saliva as the glue , reverse swing could be obtained at nominal bowling speeds on even a brand new ball, and best of all, the evidence is gone by the time the ball reaches the wicketkeeper.
Is that what Atherton was attempting? I doubt it, but I wonder if other players ever tried it, especially in the days when sawdust was routinely used to dry a wet ball. The one misconception about reverse swing that is commonly heard even today is that it occurs due to a weight imbalance created by wetting one side of the ball.
This is based on comments made by some of the early exponents of reverse swing, but it has NO scientific basis to it whatsoever.
Wetting the ball may indeed help in the gouging process, but the importance of a dry, rough surface is now well understood by the current players who are often seen avoiding hand contact with the rough surface. Another misconception is that reverse swing is more lethal because the ball swings more and late.
It turns out the side-force magnitude and direction for reverse swing are comparable to those for conventional swing and for both types of swing, the ball follows a parabolic flight path so that most of the movement occurs in the latter part of the flight.
Bottom line: late swing is "built-in. My personal attempts at ball-tampering never really materialised. By the time I figured it out, I found myself playing in California and our team captain - who was also the opening bowler - refused to let me tamper with the ball; he was convinced that my actions would "screw up" his beautiful outswing. The fact is that the condition of the "back side" of the ball the upper surface behind the seam in Figs 1 and 2 is not very critical.
So the perfect ball for conventional and reverse swing is one with one side very smooth and the other rough. There is also another advantage in creating a ball with a sharp contrast in surface roughness. Contrast swing On a visit to the ECB National Cricket Academy last December, where I was invited to present my research on cricket ball aerodynamics, I realised that there was still some confusion regarding the definition of reverse swing. They had a practice session devoted to reverse swing with specially prepared balls one side deliberately roughened.
Some of the bowlers swung the ball quite well and they thought in the reverse sense. However, the ball generally had the seam straight up not angled and swung towards the smooth side. This was obviously not reverse swing and it was somewhat difficult for me to explain to the bowlers and coaches what was going on.
That is when I developed the new term: "contrast swing". So how is contrast swing different from conventional and reverse swing? In Fig 4 a , a ball with a contrasting surface roughness is flying through the air at a relatively low speed with the seam straight up. In this case, the boundary layer over the upper surface separates relatively early in a laminar state while that on the bottom rough side becomes turbulent and separates later.
This asymmetry results in a side force which makes the ball swing towards the rough side. If the ball is released at a much higher speed, the flow field is different as shown in Fig 4 b.
In this case, transition occurs on both sides of the ball, but the turbulent boundary layer along the rough bottom surface is thickened and weakened in the same way that the seam weakens the turbulent boundary layer in reverse swing.
As a result the boundary layer on the rough side separates relatively early and the ball now swings towards the smooth side. Note that the actual critical bowling speed that determines which way the ball will swing is totally determined by the condition of the ball.
Superb examples of true contrast swing can be found in the second innings of the third Ashes Test, Flintoff to Matthew Hayden and Flintoff to Adam Gilchrist. The most exciting feature about contrast swing is that just about any bowler regardless of bowling speed can implement it in practice.
As most cricketers are aware, it is much easier to release the ball with the seam straight up, rather than angled towards the slips or fine leg. Thus, even mere mortals should be able to swing such a ball, and in either direction, since the bowling action is the same for both types of swing, the only difference being the orientation of the ball. In fact, the medium-pace "seam" or "stock" bowlers usually bowl with the seam in this orientation in an attempt to make the ball bounce on its seam so that it may gain sideways movement off the ground.
0コメント