HELPR : Sandia Energy

Sandia Energy > Programs > Sustainable Transportation > Hydrogen and Fuel Cells > Hydrogen Safety, Codes, and Standards > HELPR

Hydrogen Extremely Low Probability of Rupture (HELPR) is a modular, probabilistic fracture mechanics platform developed to assess the structural integrity of natural gas infrastructure for transmission and distribution of hydrogen natural gas blends. HELPR contains fatigue and fracture engineering models to allow fast computations while its probabilistic framework enables users to explore and characterize the sensitivity of predicted outcomes to uncertainties within the pipeline’s structure and operation.

HELPR development was supported by the Office of Energy Efficiency and Renewable Energy’s (EERE) Hydrogen and Fuel Cell Technologies Office (HFTO) within the U.S. Department of Energy (DOE).

The HELPR software is available under the open-source 3-Clause BSD License.

Github logo Access the source code for HELPR via GitHub

Windows logo Download the most recent build of the Windows installer

Download the most recent build of the macOS intel installer

Download the most recent build of the macOS appleSI installer

Overview

HELPR includes the following features:

Applicable to pressurized cylindrical shells
Fast running, deterministic engineering models
Fatigue life estimation

ASME CC2938 design curves with additional pressure compensation term
Track crack growth over time, assuming cyclic pressure loading

Stress intensity factor calculations for both finite length elliptical and long, internal flaws based on analytic solutions
Failure assessment diagrams
Probabilistic framework to provide predictions with uncertainty estimates
Support for both characterized variability and unknown uncertainties
Sensitivity studies to understand impact of input parameters on predicted quantities of interest

Given a user-defined system, HELPR can be used to:

Estimate remaining fatigue life for a set of operating conditions
Explore the impact of transporting different volume fractions of hydrogen on a pipeline’s temporal structural integrity
Determine which operational parameter variabilities have the most significant impact on a pipeline’s structural integrity

Documentation

Suggested citation for HELPR v1.1.0: Benjamin B. Schroeder, Cianan Sims, Benjamin R. Liu, Michael C. Devin, and Bailey Lucero. HELPR (Hydrogen Extremely Low Probability of Rupture), Version 1.1.0. Sandia National Laboratories (April 16, 2024); software available at: https://helpr.sandia.gov.
B. Schroeder, R. Dingreville, C. San Marchi, and J. Ronevich: “Probabilistic Fracture Mechanics Toolkit for Hydrogen Blends in Natural Gas Infrastructure”. International Hydrogen Conference, Park City, UT, 17-20 September 2023, SAND2023-08941C.
B. Schroeder, C. San Marchi, R. Dingreville, J. Ronevich: “Probabilistic Fracture Mechanics Toolkit for Hydrogen Blends in Natural Gas Infrastructure”, Emerging Fuels Symposium, 5-8 June 2023, Orlando FL, SAND2023-3992C.

Contact

Benjamin Schroeder
HELPR Team Lead
bbschro@sandia.gov

Chris San Marchi
Hydrogen Materials Expert
cwsanma@sandia.gov

Joe Ronevich
Hydrogen Materials Expert
jaronev@sandia.gov

Sample Outputs

See examples of data below that were produced using HELPR.

A line plot with rate of crack growth on the y axis and change in stress intensity factor on the x axis, where each point shown has been used in a computation. The points are compared to a design curve from ASME CC2938. — A comparison of crack growth rates exercised during a fatigue calculation with ASME CC2938 design curves.

A line plot showing an ensemble of curves with crack size normalized by pipe wall thickness on the y axis versus the total cycles on the x axis and the associated critical crack sizes for each line shown as stars on the lines. — An ensemble of crack growth temporal evolutions and the associated critical crack sizes at which crack growth is no longer stable.

A scatter plot of dots with critical crack sizes normalized by pipe wall thickness on the y axis and the number of cycles to reach the critical crack size on the x axis, with the results compared to a nominal result shown as a star. — An ensemble of critical crack sizes (normalized by pipe wall thickness) and the associated number of crack growth cycles to reach the critical crack size

A line plot showing a cumulative distribution function with cumulative probability on the y axis and the number of cycles of reach critical crack size on the x axis. The result is compared to nominal result shown as a vertical dashed line. — A cumulative distribution function (CDF) of the number of cycles to reach the critical crack size.

A failure assessment diagram with toughness ratio and load ratio as the y and x axes and a failure assessment curve shown. An ensemble of result points is compared to a nominal result point on the diagram shown as a different colored dot. — An ensemble of Failure Assessment Diagram (FAD) results.

A line plot showing an ensemble of cumulative distribution functions with the cumulate probability on the y axis and the number of cycles to the critical crack size on the x axis. The curves are compared to nominal result shown as a vertical dashed line. — Cumulative distribution functions (CDFs) of the number of cycles to reach the critical crack size where each CDF corresponds to a sample of the epistemic input uncertainties.