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Tony's Intertwingled Memex • Reference Manual

Submersible Pressure Hull Buoyancy and Hydrostatic Stability (Mechanical & Ocean Engineering)

Formulas & Definitions

A mechanical and ocean systems engineer at the UNLV Howard R. Hughes College of Engineering is modeling the hydrodynamic stability of an unmanned underwater vehicle (UUV) designed for deep-sea trench exploration.

The symmetric profile of the submerged starboard hull section is bounded on the left by the vertical keel centerline x=0x = 0x=0, at the top by the design waterline y=3y = 3y=3, and on the exterior by the logarithmic hull boundary x=ln⁡(y)x = \ln(y)x=ln(y) (for y≥1y \ge 1y≥1, dimensions in meters). The static hydrostatic buoyant pressure moment is initially modeled as a Type II horizontal integral:

M=∫13∫0ln⁡(y)y dx dyM = \int_{1}^{3} \int_{0}^{\ln(y)} y \, dx \, dyM=∫13​∫0ln(y)​ydxdy

To integrate this profile directly into the automated hydrostatics solver and calculate the vertical center of buoyancy:

  1. Extract the given Type II integration boundaries and invert the outer boundary function x=ln⁡(y)x = \ln(y)x=ln(y) to solve for yyy explicitly in terms of xxx.
  2. Determine the constant outer xxx-limits and functional inner yyy-limits required to re-slice the hull domain as a Type I vertical layout (dy dxdy \, dxdydx).
  3. Set up and evaluate the switched iterated integral M=∬Ry dAM = \iint_R y \, dAM=∬R​ydA, giving both the exact analytical expression and the rounded value to three decimal places.
  4. Explain how computing moments of area via order-switched integrals aids ocean engineers in verifying transverse metacentric height and righting arm buoyancy stability.