neqsim-flow-induced-vibration-screening

Flow-Induced Vibration Screening

Use this skill for public, educational flow-induced vibration (FIV) screening. It computes a fluid kinetic-energy index rho v^2 and compares it to a configurable kinetic-energy threshold so an agent can flag piping that may need a detailed Energy Institute style FIV likelihood-of-failure assessment before vibration design.

When to Use

• When a user asks whether a line could be prone to flow-induced vibration.
• When an agent needs a quick kinetic-energy triage to scope a piping vibration 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.
• kinetic_energy_threshold: screening kinetic-energy threshold in Pa, default 10000.0.
• small_bore_present: optional flag that a small-bore connection or thermowell is present, default False.

Outputs

• kinetic_energy_pa: fluid kinetic-energy index rho v^2 in Pa.
• threshold_ratio: ratio of the kinetic energy to the screening threshold.
• likelihood_of_failure_band: qualitative low, medium, or high band.
• fiv_warning: ok, watch, or high.
• small_bore_flag: True when a small-bore connection raises the screening sensitivity.
• assumptions: public assumptions used by the placeholder model.

Engineering Method

The Python class FlowInducedVibrationModel uses an open, published screening concept only:

• the fluid kinetic energy uses the widely published index FKE = rho v^2, the same quantity used as the primary driver in public Energy Institute style FIV likelihood-of-failure screening.
• the threshold ratio compares the kinetic energy to a configurable screening threshold.
• a small-bore connection flag lowers the effective warning thresholds because small-bore and thermowell connections are a common FIV failure location.
• the likelihood-of-failure band is a simple rule-based label derived from the threshold ratio.