A study of spin isomer conversion kinetics in supercritical fluid hydrogen for cyrogenic fuel storage technologies (original) (raw)

NASA/ADS

;

• Petitpas, Guillaume ;
• Aceves, Salvador M.

Abstract

A detailed kinetic study of para-ortho hydrogen conversion under supercritical conditions using rotational Raman scattering is presented. Isochoric measurements of initially low ortho concentrations over temperatures 32 < T < 280 K and densities 0.014 < ρ < 0.060 g/cm3 were used to derive kinetic rate constants k(ρ, T) by solving an autocatalytic kinetic rate equation. At low ortho concentrations and T < 100 K, k is found to be ∼2× higher than previous results based on thermal conductivity measurements, decreasing weakly with temperature, similar to Wigner's original paramagnetic theory. Accurate modeling of k(ρ, T) is critical in predicting cryogenic hydrogen fuel tank dormancy performance for hydrogen-power vehicles.

Publication:

Applied Physics Letters

Pub Date:

August 2011

DOI:

10.1063/1.3628453

Bibcode:

2011ApPhL..99h1906M

Keywords:

• catalysis;
• cryogenics;
• fuel storage;
• hydrogen storage;
• Raman spectra;
• thermal conductivity;
• 88.30.R-;
• 07.20.Mc;
• Cryogenics;
• refrigerators low-temperature detectors and other low-temperature equipment