neqsim-pressure-drop-screening

Pressure Drop Screening

Use this skill for public, educational line pressure-drop screening. It estimates a single-phase Darcy-Weisbach pressure gradient and compares it to a recommended pressure-gradient guideline so an agent can flag lines that may exceed standard hydraulic limits before moving to validated line sizing.

When to Use

• When a user asks whether a line pressure drop sits within recommended limits.
• When an agent needs a quick pressure-gradient triage to scope a hydraulic or debottlenecking study.
• When examples must run without confidential piping classes, project line lists, or company piping specs.

Inputs

• fluid_velocity: actual flowing velocity in the line in m/s.
• mixture_density: flowing mixture density in kg/m3.
• viscosity: flowing dynamic viscosity in Pa.s.
• pipe_inner_diameter: pipe inner diameter in m.
• length: line length used for the total pressure drop in m, default 100.0.
• roughness: absolute pipe roughness in m, default 4.6e-5 (commercial steel).
• guideline_bar_per_100m: recommended maximum pressure gradient in bar per 100 m, default 0.5.

Outputs

• reynolds_number: flow Reynolds number.
• friction_factor: Darcy friction factor from laminar or Haaland turbulent form.
• dp_per_100m_bar: screening pressure gradient in bar per 100 m.
• dp_total_bar: screening total pressure drop over the line length in bar.
• guideline_ratio: ratio of the pressure gradient to the recommended guideline.
• pressure_drop_warning: ok, watch, or high.
• assumptions: public assumptions used by the placeholder model.

Engineering Method

The Python class PressureDropModel uses open, published correlations only:

• the Reynolds number uses the standard Re = rho v D / mu form.
• the friction factor uses f = 64 / Re in laminar flow and the public Haaland explicit approximation of the Colebrook equation in turbulent flow.
• the pressure gradient uses the Darcy-Weisbach form dP/L = f (1/D) (rho v^2 / 2).
• the guideline ratio compares the pressure gradient to a configurable recommended gradient aligned with NORSOK P-002 and GPSA style line pressure-gradient guidelines.