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Turbulence is the most important unsolved problem of classical physics.

Richard P. Feynman

Field notes from a compressible multiphase CFD researcher

WEEKLYMONCFD TechniquesTUEFluid MechanicsWEDCFD TechniquesTHUFluid MechanicsFRICFD TechniquesSATPaper ReviewSUNPaper Review

Top posts this week

FILTER
#122
SUN
2026.08.02

[Paper Review] How to Delete Under-Relaxation — Linearisation in a Coupled Pressure-Based Solver

Why fixed-coefficient vs Newton linearisation decides all-Mach convergence

11 min read#논문리뷰 #Pressure-Based #Coupled-Solver
#121
SAT
2026.08.01

[Paper Review] A Droplet Sends Almost Every Sound Wave Back — Acoustic Impedance and a Sharp-Interface Two-Phase Solver

Why a liquid-gas interface reflects 99.9% of an acoustic wave, and the fake sound speed a smeared interface invents

9 min read#논문리뷰 #Compressible #Multiphase
#120
FRI
2026.07.31

Where Jacobi Dies on a Boundary-Layer Mesh — the Linelet Line-Implicit Preconditioner

Why squashing cells toward the wall stalls point smoothers, and the fix

9 min read#Linelet #Preconditioning #Anisotropic-Grid
#119
THU
2026.07.30

Why Laundry Dries at 5 °C — Diffusion-Limited Evaporation vs. Heat-Driven Boiling

Why non-boiling and boiling evaporation need different source terms

10 min read#Phase-Change #Evaporation #Multiphase
#118
WED
2026.07.29

The Mesher That Dies Defending Your Boundary — Constrained Delaunay and Steiner Points

Why tetgen collapses on 8.5% of valid models, and how segment and facet recovery works

11 min read#Mesh-Generation #Delaunay #Steiner-Point
#117
TUE
2026.07.28

Where Turbulence Stops Speeding Up a Flame — Damköhler's Wrinkling Hypothesis and Bending

The physics behind the three regimes of the turbulent flame speed curve: linear rise, bending, quenching

12 min read#Combustion #Turbulence #Premixed-Flame
#116
MON
2026.07.27

Where Half the Force Goes in LBM — Four Forcing Schemes and 1−1/(2τ)

Comparing lattice Boltzmann body-force schemes and pinning down the half-force correction

14 min read#LBM #Forcing-Term #Guo-Forcing
#115
SUN
2026.07.26

The Mach Number Goes to Zero, the Time Step Doesn't Budge — Reproducing an IMEX TVD Scheme

A second-order IMEX scheme that escapes the acoustic CFL without oscillating

12 min read#IMEX #Asymptotic-Preserving #Low-Mach
#114
SAT
2026.07.25

Un-smearing the Interface Every Step — Implementing Anti-Diffusion Sharpening (IST)

A post-processing technique that pins a numerically smeared interface to a constant thickness

7 min read#논문리뷰 #Interface-Sharpening #Diffuse-Interface
#113
FRI
2026.07.24

Supersonic Flow Can't See Upstream — Characteristics and Sound Waves in the Euler Equations

Why a small disturbance splits into three characteristic speeds

7 min read#Characteristics #Compressible #Euler-Equations
#112
THU
2026.07.23

How Far Must Water Flow Before It Becomes a Parabola — Entrance Length and Hagen–Poiseuille

The pipe entrance region, the Hagen–Poiseuille parabola, and the 64/Re friction factor

4 min read#Pipe-Flow #Boundary-Layer #Hagen-Poiseuille
#111
WED
2026.07.22

When Pressure Rings in a Checkerboard — SIMPLE and Rhie-Chow Coupling

Why collocated pressure checkerboards, how Rhie-Chow fixes it, and the SIMPLE loop

6 min read#SIMPLE #Rhie-Chow #Pressure-Velocity-Coupling
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