Magnetic Resonance Velocimetry (MRV) is a non-invasive imaging technique used to measure the velocity of fluid flow. It utilizes the principles of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) to visualize and quantify flow in various applications, including biomedical settings, engineering, and fluid dynamics research.
The Moens–Korteweg equation refers to a specific mathematical model that describes the propagation of waves in a fluid-filled elastic tube. It is commonly used in the study of hemodynamics, particularly to understand how blood flows in arteries, but it has applications in various fields involving fluid dynamics and elastic materials. The equation itself is a modification of the classical wave equation and incorporates factors such as the elastic properties of the tube, fluid characteristics, and geometric considerations.
Nonlinear frictiophoresis is a phenomenon related to the movement of particles in a fluid due to frictional interactions between the particles and the fluid. This process becomes nonlinear when the forces acting on the particles do not follow a simple linear relationship, often influenced by the particle size, shape, and the flow characteristics of the surrounding fluid.
Noncontracting grammar is a term related to a type of formal grammar in the field of computer science and computational linguistics. It describes a specific class of grammar where the production rules do not allow certain kinds of reductions or contractions of strings. In simpler terms, in noncontracting grammars, the length of the string produced by the grammar does not decrease; it either stays the same or increases with each application of a production rule.
Ogden's lemma is a result in formal language theory, specifically concerning context-free languages (CFLs). It is a generalization of the well-known Pumping Lemma for context-free languages. Ogden's lemma provides a method for proving that certain languages are not context-free by demonstrating that a language does not satisfy the conditions required by the lemma.
Neumann's Law, often referred to in the context of thermodynamics and heat transfer, is typically associated with the behavior of heat conduction in materials. It states that the heat flux out of a material is proportional to the temperature gradient within that material, usually expressed mathematically by Fourier's law of heat conduction. In a broader context, the law may also refer to various principles in physics and mathematics related to von Neumann's work, such as in quantum mechanics or game theory.
Algorithmic Geometry, often referred to as Computational Geometry, is a branch of computer science and mathematics that focuses on the study of geometric objects and the design of algorithms for solving geometric problems. It combines concepts from geometry, algorithms, and data structures to address questions about shapes, sizes, relative positions of figures, and their properties.
"Kaye and Laby" refers to the "Kaye and Laby: Tables of Physical and Chemical Constants," which is a reference book widely used in the fields of physics and chemistry. The book contains a comprehensive collection of tables that provide various physical and chemical constants, properties of materials, and other essential data that researchers and scientists often require. Originally compiled by Sir J. H. Kaye and Sir D. W.
Eddy diffusion is a process that describes the transport and mixing of particles, heat, or other substances in a medium, such as air or water, due to turbulent eddies or vortices. This phenomenon is particularly important in the fields of fluid dynamics, meteorology, oceanography, and environmental science. In turbulent flows, eddies of varying sizes are created as a result of chaotic fluid motion.
The Immersed Boundary Method (IBM) is a numerical technique used to study fluid-structure interactions, particularly in scenarios where flexible boundaries or immersed structures interact with a flowing fluid. This method was first introduced by Charles S. Peskin in the 1970s and has since become a powerful tool in computational fluid dynamics (CFD).
Inertance
Inertance is a term used in the field of mechanical engineering and dynamics, particularly in systems involving vibrations and dynamic responses. It is analogous to mass in electrical systems and is a measure of the inertia of a system when responding to dynamic inputs, such as forces or accelerations. Inertance can be defined as the ratio of the force applied to a system to the resulting acceleration of that system.
In fluid dynamics, the Laplace equation is often applied in the context of irrotational flow, which is characterized by the absence of vorticity. For an incompressible, irrotational flow, the flow velocity can be described with a potential function, commonly denoted as \( \phi \).
Lapse rate
Lapse rate refers to the rate at which temperature decreases with an increase in altitude in the atmosphere. It is a critical concept in meteorology and atmospheric science. There are different types of lapse rates, including: 1. **Environmental Lapse Rate (ELR)**: This is the actual rate of temperature change with altitude in the atmosphere at a given time and place. It can vary significantly depending on the weather conditions and location.
Large Eddy Simulation (LES) is a computational fluid dynamics technique used to simulate turbulent fluid flows. It is particularly effective for resolving the large-scale motions of turbulence while modeling the smaller-scale motions. ### Key Components of LES: 1. **Spatial Filtering**: In LES, the governing equations of fluid dynamics (like the Navier-Stokes equations) are filtered to separate the large eddies (large-scale turbulent structures) from the small eddies (small-scale turbulent structures).
Parachor
Parachor is a concept used in the field of physical chemistry, particularly in the study of surface tension of liquids and the properties of surfactants. It refers to a dimensionless quantity that can be used to characterize the surface tension of a liquid relative to its molecular weight or volume.
Weight
Weight is a measure of the force exerted on an object due to gravity. It is often confused with mass, which is a measure of the amount of matter in an object. Weight is dependent on both the mass of the object and the strength of the gravitational field acting upon it.
A central force is a type of force that acts on an object directed towards a fixed point, known as the center. The key characteristics of a central force include: 1. **Direction**: The force always points either directly toward or directly away from the center. 2. **Magnitude**: The strength or magnitude of the force can vary with the distance from the center, but it is always a function of that distance.
Convergence of probability measures is a concept in probability theory that deals with how a sequence of probability measures converges to a limiting probability measure. There are several modes of convergence that characterize this behavior, and each is important in different contexts, particularly in statistics, stochastic processes, and analysis.
The Algebraic Riccati Equation (ARE) is a type of matrix equation that arises in various fields, including control theory, especially in linear quadratic optimal control problems. The general form of the Algebraic Riccati Equation is: \[ A^T X + X A - X B R^{-1} B^T X + Q = 0 \] where: - \( X \) is the unknown symmetric matrix we are trying to solve for.
Aeolian sound refers to sound that is produced by the movement of air, particularly wind, interacting with objects in the environment. The term "Aeolian" is derived from Aeolus, the ancient Greek god of the winds. Aeolian sounds can occur naturally, such as the whistling of wind through trees, the rustling of leaves, or the sound of wind blowing across open landscapes, including hills and dunes.