STELLA NOVAEDUCATION

Hydrodynamic Flow Model Tester

Virtual Water Tunnel for Fully Submerged Objects

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ANALYTICAL PREVIEWAdaptive browser renderer
Drag to orbit · Wheel/pinch to zoom · Shift-drag to pan
Pressure Coefficient (Cp)
-1.50-1.00-0.500.000.501.001.50
Velocity Magnitude (m/s)
01.252.53.755.06.257.58.7510.0

METHODOLOGY & THEORY (Inline PDF)

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SCHOLARLY ANNOTATIONS & DISCUSSION (No-database JSON)

Comments are stored in a local JSON file on this Stella Nova installation. Uploaded STL geometry remains in the browser and is never included in comments or reports.

METHODS REFERENCE

Equations, assumptions, and analysis pathways

Each equation is linked to a visible output or solver stage. The browser preview uses analytical resistance estimates; numerical mode adds a coarse D3Q19 lattice-Boltzmann flow field and reports its resolution and similarity limits.

01

Continuity

∇ · u = 0\nabla \cdot \mathbf{u}=0

Incompressible mass conservation. Used as the target condition for the numerical flow field.

02

Momentum

∂u/∂t + (u · ∇)u = -(1/ρ)∇p + ν∇²u\frac{\partial \mathbf{u}}{\partial t}+(\mathbf{u}\cdot\nabla)\mathbf{u}=-\frac{1}{\rho}\nabla p+\nu\nabla^2\mathbf{u}

Incompressible Navier-Stokes form governing pressure and viscous momentum transport.

03

Reynolds number

Re = UL/ν = ρUL/μRe=\frac{UL}{\nu}=\frac{\rho UL}{\mu}

Controls similarity and indicates whether viscous or inertial effects dominate.

04

Hydrodynamic force

F = ∫S(-pn + τ · n) dA\mathbf{F}=\int_S\left(-p\mathbf{n}+\boldsymbol{\tau}\cdot\mathbf{n}\right)dA

Separates pressure resistance from surface-shear resistance.

05

Drag coefficient

CD = FD / (½ρU²Aref)C_D=\frac{F_D}{\tfrac12\rho U^2A_{ref}}

Normalizes resistance for comparison across speeds, sizes, and water conditions.

06

ITTC friction line

CF = 0.075 / (log10Re - 2)²C_F=\frac{0.075}{(\log_{10}Re-2)^2}

Used as a turbulent smooth-surface friction reference, not as total body drag.

07

Pressure coefficient

Cp = (p - p∞) / (½ρU²)C_p=\frac{p-p_\infty}{\tfrac12\rho U^2}

Drives the surface-pressure visualization and stagnation-zone interpretation.

08

Cavitation number

σ = (p∞ - pv) / (½ρU²)\sigma=\frac{p_\infty-p_v}{\tfrac12\rho U^2}

Provides a screening margin only; version one does not solve multiphase cavitation.

Core references

  1. ITTC. 2024. Resistance Test, Recommended Procedure 7.5-02-02-01.
  2. IOC, SCOR, and IAPSO. 2010. The International Thermodynamic Equation of Seawater - 2010 (TEOS-10). UNESCO Manuals and Guides No. 56.
  3. IAPWS. 2008. Release on the IAPWS Formulation 2008 for the Viscosity of Ordinary Water Substance.
  4. d'Humières, D., I. Ginzburg, M. Krafczyk, P. Lallemand, and L.-S. Luo. 2002. “Multiple-relaxation-time lattice Boltzmann models in three dimensions.” Philosophical Transactions A 360:437-451.
  5. Bouzidi, M., M. Firdaouss, and P. Lallemand. 2001. “Momentum transfer of a Boltzmann-lattice fluid with boundaries.” Physics of Fluids 13:3452-3459.
  6. Groves, N. C., T. T. Huang, and M. S. Chang. 1989. Geometric Characteristics of DARPA SUBOFF Models. David Taylor Research Center Report DTRC/SHD-1298-01.
INTERPRETIVE SCOPE

A visual model tester with explicit numerical limits

The tester is intended for design comparison, teaching, and preliminary analysis. It is not a substitute for a validated engineering CFD workflow, tow-tank experiment, or certification analysis. Uploaded models remain local to the browser. Every numerical run records its grid, convergence history, blockage ratio, and similarity warning so the result can be interpreted rather than merely admired.