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Iribarren Number
In fluid dynamics, the Iribarren number or Iribarren parameter – also known as the surf similarity parameter and breaker parameter – is a dimensionless parameter used to model several effects of (breaking) surface gravity waves on beaches and coastal structures. The parameter is named after the Spanish engineer Ramón Iribarren Cavanilles (1900–1967), who introduced it to describe the occurrence of wave breaking on sloping beaches. The parameter used to describe breaking wave types on beaches; or wave run-up on – and reflection by – beaches, breakwaters and dikes. Iribarren's work was further developed by Jurjen Battjes in 1974, who named the parameter after Iribarren. Definition The Iribarren number which is often denoted as ''Ir'' or ''ξ'' – is defined as: :\xi = \frac, with L_0 = \frac\, T^2, where ''ξ'' is the Iribarren number, is the angle of the seaward slope of a structure, ''H'' is the wave height, ''L''0 is the deep-water wavelength, ''T'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Free Surface
In physics, a free surface is the surface of a fluid that is subject to zero parallel shear stress, such as the interface between two homogeneous fluids. An example of two such homogeneous fluids would be a body of water (liquid) and the air in the Earth's atmosphere (gas mixture). Unlike liquids, gases cannot form a free surface on their own. Fluidized/ liquified solids, including slurries, granular materials, and powders may form a free surface. A liquid in a gravitational field will form a free surface if unconfined from above. Under mechanical equilibrium this free surface must be perpendicular to the forces acting on the liquid; if not there would be a force along the surface, and the liquid would flow in that direction. Thus, on the surface of the Earth, all free surfaces of liquids are horizontal unless disturbed (except near solids dipping into them, where surface tension distorts the surface in a region called the meniscus). In a free liquid that is not affecte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurjen Battjes
Jurjen Anno Battjes (born 22 February 1939) is a Dutch civil engineer. He was a professor of fluid dynamics at Delft University of Technology until his retirement in 2004. Battjes was elected an international member of the National Academy of Engineering in 2009 for international leadership, research, and teaching in coastal engineering and storm protection. Career Battjes was born on 22 February 1939 in Winschoten. He studied civil engineering at Delft University of Technology, earning his M.Sc in 1962. Battjes subsequently spent four years as an assistant professor at the Laboratory of Coastal Engineering at the University of Florida, in the United States. He started working as a professor at Delft University of Technology in the late 1960s, where he held the chair of fluid dynamics. In 1974 Battjes obtained his Doctor title in technical sciences at Delft University under Johan Schönfeld, with a thesis titled ''Computation of Set-up, Longshore Currents, Run-up and Overtopping d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Waves
In fluid dynamics, a wind wave, or wind-generated water wave, is a surface wave that occurs on the free surface of bodies of water as a result of the wind blowing over the water's surface. The contact distance in the direction of the wind is known as the '' fetch''. Waves in the oceans can travel thousands of kilometers before reaching land. Wind waves on Earth range in size from small ripples to waves over high, being limited by wind speed, duration, fetch, and water depth. When directly generated and affected by local wind, a wind wave system is called a wind sea. Wind waves will travel in a great circle route after being generated – curving slightly left in the southern hemisphere and slightly right in the northern hemisphere. After moving out of the area of fetch and no longer being affected by the local wind, wind waves are called '' swells'' and can travel thousands of kilometers. A noteworthy example of this is waves generated south of Tasmania during heavy win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Wave
In fluid dynamics, a wind wave, or wind-generated water wave, is a surface wave that occurs on the free surface of bodies of water as a result of the wind blowing over the water's surface. The contact distance in the direction of the wind is known as the '' fetch''. Waves in the oceans can travel thousands of kilometers before reaching land. Wind waves on Earth range in size from small ripples to waves over high, being limited by wind speed, duration, fetch, and water depth. When directly generated and affected by local wind, a wind wave system is called a wind sea. Wind waves will travel in a great circle route after being generated – curving slightly left in the southern hemisphere and slightly right in the northern hemisphere. After moving out of the area of fetch and no longer being affected by the local wind, wind waves are called '' swells'' and can travel thousands of kilometers. A noteworthy example of this is waves generated south of Tasmania during heavy wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periodic Wave
A periodic function, also called a periodic waveform (or simply periodic wave), is a function that repeats its values at regular intervals or periods. The repeatable part of the function or waveform is called a ''cycle''. For example, the trigonometric functions, which repeat at intervals of 2\pi radians, are periodic functions. Periodic functions are used throughout science to describe oscillations, waves, and other phenomena that exhibit periodicity. Any function that is not periodic is called ''aperiodic''. Definition A function is said to be periodic if, for some nonzero constant , it is the case that :f(x+P) = f(x) for all values of in the domain. A nonzero constant for which this is the case is called a period of the function. If there exists a least positive constant with this property, it is called the fundamental period (also primitive period, basic period, or prime period.) Often, "the" period of a function is used to mean its fundamental period. A function ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breaking Wave Types
Breaking or breakin' may refer to: Arts * Breaking character (or "corpsing"), to lose composure during comedic scenes * Breakdancing (also breaking), an athletic style of street dance * ''Breakin''', a 1984 American breakdancing-themed musical film * "Breakin, a twelfth-season episode of the American animated television series ''SpongeBob SquarePants'' * ''Breaking'' (film), a 2022 American thriller drama film * Sequence breaking, performing actions or obtaining items in video games out of the intended linear order Music * "Breakin (song), a single from The Music's album, ''Welcome to the North'' * " Breakin'... There's No Stopping Us", a song by American music duo Ollie & Jerry * "Breakin, the sixth song on The All-American Rejects' 2008 album '' When the World Comes Down'' * ''Breaking'' (album), an album by American musician Brian Larsen * "Breaking" (song), a song by American alternative rock band, Anberlin Damage * Breaking (martial arts), technique that is used in comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Significant Wave Height
In physical oceanography, the significant wave height (SWH, HTSGW or ''H''s) is defined traditionally as the mean ''wave height'' (trough (physics), trough to crest (physics), crest) of the highest third of the ocean surface wave, waves (''H''1/3). It is usually defined as four times the standard deviation of the surface elevation – or equivalently as four times the square root of the zeroth-order moment (area) of the ''wave spectrum''. The symbol ''H''m0 is usually used for that latter definition. The significant wave height (Hs) may thus refer to ''H''m0 or ''H''1/3; the difference in magnitude between the two definitions is only a few percent. SWH is used to characterize ''sea state'', including winds and swell (ocean), swell. Origin and definition The original definition resulted from work by the oceanographer Walter Munk during World War II. The significant wave height was intended to mathematically express the height estimated by a "trained observer". It is commonly used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surf Zone
The surf zone or breaker zone is the nearshore part of a body of open water between the line at which the waves break and the shore. As ocean surface waves approach a shore, they interact with the bottom, wave shoaling, get taller and steeper, and break, forming the sea foam, foamy surface called ''surf''. The region of breaking waves defines the surf zone. After breaking in the surf zone, the waves (now reduced in height) continue to move in, and they run up onto the sloping front of the beach, forming an uprush of water called swash. The water then runs back again as Swash#Backwash current, backwash. The water in the surf zone is relatively shallow, depending on the height and period of the waves. Animal life The animals that often are found living in the surf zone are crabs, clams, and snails. Surf clams and mole crabs are two species that stand out as inhabitants of the surf zone. Both of these animals are very fast burrowers. The surf clam, also known as the variable coquina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity Of Earth
The gravity of Earth, denoted by , is the net force, net acceleration that is imparted to objects due to the combined effect of gravitation (from mass distribution within Earth) and the centrifugal force (from the Earth's rotation). It is a Euclidean vector, vector quantity, whose direction coincides with a plumb bob and strength or magnitude is given by the Euclidean norm, norm g=\, \mathit\, . In International System of Units, SI units, this acceleration is expressed in metre per second squared, metres per second squared (in symbols, metre, m/second, s2 or m·s−2) or equivalently in Newton (unit), newtons per kilogram (N/kg or N·kg−1). Near Earth's surface, the acceleration due to gravity, accurate to 2 significant figures, is . This means that, ignoring the effects of drag (physics), air resistance, the speed of an object free fall, falling freely will increase by about every second. The precise strength of Earth's gravity varies with location. The agreed-upon value for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency
Frequency is the number of occurrences of a repeating event per unit of time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light. The interval of time between events is called the period. It is the reciprocal of the frequency. For example, if a heart beats at a frequency of 120 times per minute (2 hertz), its period is one half of a second. Special definitions of frequency are used in certain contexts, such as the angular frequency in rotational or cyclical properties, when the rate of angular progress is measured. Spatial frequency is defined for properties that vary or cccur repeatedly in geometry or space. The unit of measurement of frequency in the International System of Units (SI) is the hertz, having the symbol Hz. Definitions and units For cyclical phenomena such as oscillations, waves, or for examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wavelength
In physics and mathematics, wavelength or spatial period of a wave or periodic function is the distance over which the wave's shape repeats. In other words, it is the distance between consecutive corresponding points of the same ''phase (waves), phase'' on the wave, such as two adjacent crests, troughs, or zero crossings. Wavelength is a characteristic of both traveling waves and standing waves, as well as other spatial wave patterns. The multiplicative inverse, inverse of the wavelength is called the ''spatial frequency''. Wavelength is commonly designated by the Greek letter lambda (''λ''). For a modulated wave, ''wavelength'' may refer to the carrier wavelength of the signal. The term ''wavelength'' may also apply to the repeating envelope (mathematics), envelope of modulated waves or waves formed by Interference (wave propagation), interference of several sinusoids. Assuming a sinusoidal wave moving at a fixed phase velocity, wave speed, wavelength is inversely proportion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wave Height
In fluid dynamics, the wave height of a surface wave is the difference between the elevations of a crest and a neighboring trough. ''Wave height'' is a term used by mariners, as well as in coastal, ocean and naval engineering. At sea, the term ''significant wave height'' is used as a means to introduce a well-defined and standardized statistic to denote the characteristic height of the random waves in a '' sea state'', including wind sea and swell. It is defined in such a way that it more or less corresponds to what a mariner observes when estimating visually the average wave height. Definitions Depending on context, wave height may be defined in different ways: *For a sine wave, the wave height ''H'' is twice the amplitude (i.e., the '' peak-to-peak amplitude''): H = 2a. *For a periodic wave, it is simply the difference between the maximum and minimum of the surface elevation : H = \max\left\ - \min\left\, with ''c''p the phase speed (or propagation speed) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
