Fluid Mechanics

Articles in this category.

Kelvin WedgeReading NoteIn Progress

What does $x^{\prime}$ mean in a Green’s function? — a linear algebra and operator view

In a Green's function \(G(x,x')\), the primed variable \(x'\) marks the source point — the location of a unit impulse — while \(x\) is the field point where the response is…

Fluid Mechanics
Kelvin WedgeReading NoteIn Progress

From the Spectral Dirichlet-Neumann Symbol to the Physical-Space Operator Identity

We show how the spectral relation ∑ Formula implies the physical-space operator identity ∑ Formula, by inverse Fourier transform and the commutation of \(\partial_z\) with the hori…

Fluid Mechanics
Kelvin WedgeDerivationNegative Result

Fourier Coefficients of Quadratic Forms in $\cos \gamma$ for Steady Capillary-Gravity Waves

The math is sound. The method is not. We factor the quadratic denominator \(a+b \cos \gamma+c \cos ^2 \gamma\) and reduce the computation of its Fourier coefficients to those of ∑ Formula.…

Fluid Mechanics
Kelvin WedgeDerivationNegative Result

Diagonalizing Azimuthal Mode Coupling via a Discrete Fourier Transform

The math is sound. The method is not. We recast the azimuthal mode-coupled surface equations as a block-Toeplitz convolution in the mode index and diagonalize this coupling via…

Fluid Mechanics
Kelvin WedgeDerivationNegative Result

Cartesian Derivatives in Azimuthal Fourier–Hankel Space

The math is sound. The method is not. claim: ∑ Formula

Fluid Mechanics
Kelvin WedgeDerivationNegative Result

DFT Method Main

The math is sound. The method is not. We consider the governing equations for water waves in the context of an inviscid fluid of infinite depth. The fundamental system of…

Fluid Mechanics
Kelvin WedgeDerivationNegative Result

Azimuthal Fourier Analysis

The math is sound. The method is not. We introduce azimuthal Fourier expansion for functions with circular symmetry: we write \(f(r, \phi)\) as a sum of angular modes ∑ Formula, whe…

Fluid Mechanics
Kelvin WedgeDerivationNegative Result

Operator Ladder Relations for Hankel Transforms of Bessel Type

The math is sound. The method is not. Hankel–Bessel Ladder Identities Claim. For suitable \(f_m(r)\) and \(k>0\), ∑ Formula Here ∑ Formula.

Fluid Mechanics
PINN Ocean Flow

settings for PINN

basic concept ninja ninja is a build system—a tool that actually runs the compile and link commands for a software project. Think of it as a faster, more streamlined replacement…

Fluid Mechanics
Kelvin WedgeReading Note

Surface Waves Generated by A Travelling Pressure Point

We study the free-surface response to a moving pressure point over finite depth using 2D Fourier transforms, contour deformation, and a radiation condition. By analysing poles…

Fluid Mechanics
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