HydDown

Downloads

  • PDF
  • EPUB

User Guide

  • Introduction
    • Citing HydDown
    • Background
    • Getting the software
    • Requirements
    • Testing
    • Units of measure
    • Credit
    • License
  • Usage
    • Basic usage
    • Demos
    • Calculation methods
    • Script
    • Module import
    • Input file examples
    • Input fields and hierarchy
      • Calculation
      • Vessel
      • Initial
      • Valve
      • Heat transfer
      • Validation
  • Theory
    • Thermodynamics
      • Equation of state
      • First law for flow process
    • Flow devices
      • Restriction Orifice
      • HEM orifice release
      • Pressure safety valve / Relief valve
      • Control Valve
    • Heat transfer
      • Natural convection
      • Mixed convection
      • Nucleate boiling heat transfer
      • Conduction
        • Biot number calculation in lumped models
      • Fire heat loads
    • Vessel geometry
    • Rupture evaluation
    • Model implementation
      • Isothermal process
      • Isenthalpic process
      • Isentropic process
      • Isenergetic process
      • Energy balance
    • Multicomponent mixtures
  • Validation
    • Hydrogen discharge (Type I)
    • Hydrogen filling (Type I)
    • Nitrogen discharge (Type I)
    • Multi-component discharge (Type I)
    • 1-D transient heat transfer
      • Validation against commercial simulation tool
      • Validation against KIT experiment (Type IV)
    • Validation against GasTeF experiments (Type IV)
    • Validation against Type III cylinder discharge experiments
    • Validation against Type III cylinder filling experiments
    • Validation of fire heat load
  • Example use cases
    • LPG vessel subject to fire heat load
      • LPG vessel with 1-D heat transfer
    • Rupture estimation
    • Composite cylinder subject to blowdown
  • Installation
    • Requirements
    • Installation via pip
    • Installation from Source
    • Dependencies
    • Optional Dependencies
  • Quick Start
    • Basic Usage
    • Simple Example
    • Streamlit Application
      • Available Streamlit Apps
    • Example Files
  • Examples
    • Vessel Depressurization
      • Isentropic Depressurization
    • Vessel Filling
      • Filling with Heat Transfer
    • Fire Scenario
      • Pool Fire Heat Load
    • Relief Valve Sizing
      • API 521 Relief Valve
    • Two-Phase Calculations
      • Liquid Hydrogen Storage

API Reference

  • hdclass - Main Calculation Engine
    • HydDown
      • HydDown.__init__()
      • HydDown.validate_input()
      • HydDown.read_input()
      • HydDown.initialize()
      • HydDown.calc_liquid_level()
      • HydDown.PHres()
      • HydDown.PHres_relief()
      • HydDown.PHproblem()
      • HydDown.UDres()
      • HydDown.UDproblem()
      • HydDown.run()
      • HydDown.get_dataframe()
      • HydDown.plot()
      • HydDown.plot_envelope()
      • HydDown.plot_tprofile()
      • HydDown.analyze_rupture()
      • HydDown.generate_report()
    • Key Classes
      • HydDown
        • HydDown
      • Key Methods
    • Implementation Notes
      • Time Integration
      • Calculation Types
  • transport - Heat and Mass Transfer
    • Gr()
    • Pr()
    • Nu()
    • h_inside()
    • h_inner()
    • h_inside_mixed()
    • h_inner_mixed()
    • h_inside_liquid()
    • h_inside_wetted()
    • hem_release_rate()
    • gas_release_rate()
    • relief_valve()
    • api_psv_release_rate()
    • cv_vs_time()
    • control_valve()
    • Dimensionless Numbers
    • Heat Transfer Coefficients
    • Mass Flow Rate Calculations
    • Valve Types
  • fire - Fire Heat Load Modeling
    • stefan_boltzmann()
    • pool_fire_api521()
    • pool_fire_scandpower()
    • jet_fire_api521()
    • jet_fire_scandpower()
    • jet_fire_peak_large_scandpower()
    • jet_fire_peak_small_scandpower()
    • pool_fire_peak_scandpower()
    • sb_fire()
    • Predefined Fire Scenarios
    • Stefan-Boltzmann Calculation
    • Usage Example
  • thermesh - 1-D Transient Heat Conduction
    • solve_ht()
    • Domain
      • Domain.mesh
      • Domain.bc
      • Domain.constitutive_model
      • Domain.t
      • Domain.T
      • Domain.q
      • Domain.timestep()
      • Domain.system_matrices()
      • Domain.check_bc()
      • Domain.set_T()
      • Domain.clear()
      • Domain.__init__()
      • Domain.timestep()
      • Domain.system_matrices()
      • Domain.check_bc()
      • Domain.set_T()
      • Domain.set_q()
      • Domain.clear()
    • isothermal_model()
    • piecewise_linear_model()
    • Mesh
      • Mesh.nodes
      • Mesh.elem
      • Mesh.nn
      • Mesh.nel
      • Mesh.subdomain
      • Mesh.__init__()
    • Element
      • Element.order
      • Element.dim
      • Element.dim
      • Element.order
      • Element.__init__()
      • Element.length()
    • LinearElement
      • LinearElement.K()
      • LinearElement.C()
      • LinearElement.order
      • LinearElement.K()
      • LinearElement.C()
    • QuadraticElement
      • QuadraticElement.K()
      • QuadraticElement.C()
      • QuadraticElement.order
      • QuadraticElement.K()
      • QuadraticElement.C()
    • Overview
    • Key Features
    • Applications
    • Wall Heat Conduction Modes
    • Composite Materials
    • Two-Phase Modeling
  • validator - Input Validation
    • validate_mandatory_ruleset()
    • heat_transfer_validation()
    • valve_validation()
    • validation()
  • materials - Material Properties
    • von_mises()
    • ATS()
    • UTS()
    • steel_Cp()

Additional Information

  • Citing HydDown
    • Primary Citation
    • Manual Citation
    • Related Publications
  • Changelog
    • Latest Version
    • Previous Versions
HydDown
  • Search

© Copyright 2026, Anders Andreasen.

Built with Sphinx using a theme provided by Read the Docs.