Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

MEASUREMENTS OF EFFECTIVE DIFFUSION COEFFICIENT OF HELIUM AND HYDROGEN THROUGH GYPSUM

Published

Author(s)

Jiann Yang, William M. Pitts, Marco Fernandez, Kuldeep Prasad

Abstract

An experimental apparatus, which was based on the ¿-scale garage previously used for studying helium release and dispersion in our laboratory, was used to obtain effective diffusion coefficients of helium and hydrogen (released as forming gas for safety reasons) through gypsum panel. Two types of gypsum panel were used in the experiments. Helium or forming gas was released into the enclosure from a Fischer burner located near the enclosure floor for a fixed duration and then terminated. Eight thermal-conductivity sensors mounted at different vertical locations above the enclosure floor were used to monitor the temporal and spatial gas concentrations. An electric fan was used inside the enclosure to mix the released gas to ensure a spatially uniform gas concentration to minimize stratification. The temporal variations of the pressure difference between the enclosure interior and the ambience were also measured. An analytical model was developed to extract the effective diffusion coefficients from the experimental data. The determined average effective diffusion coefficient of helium through gypsum panel was 1.3 × 10-5 m2/s and 1.4 × 10-5 m2/s for hydrogen.
Proceedings Title
Proceedings of the 4th International Conference on Hydrogen Safety
Conference Dates
September 12-14, 2011
Conference Location
San Francisco, CA, US

Keywords

Diffusion, Dispersion, Fire Safety, Garage, Gypsum, Helium, Hydrogen, Sensors

Citation

Yang, J. , Pitts, W. , Fernandez, M. and Prasad, K. (2011), MEASUREMENTS OF EFFECTIVE DIFFUSION COEFFICIENT OF HELIUM AND HYDROGEN THROUGH GYPSUM, Proceedings of the 4th International Conference on Hydrogen Safety, San Francisco, CA, US (Accessed November 10, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created September 14, 2011, Updated October 9, 2024