A computational study for combustion flow fields of a high-pressure gaseous hydrogen/oxygen coflow jet behind a splitter plate

2019 ◽  
Author(s):  
Shun Murakami ◽  
Hiroshi Terashima ◽  
Nobuyuki Oshima
Keyword(s):  
High Pressure ◽  
Computational Study ◽  
Flow Fields ◽  
Gaseous Hydrogen ◽  
Splitter Plate ◽  
Combustion Flow

Weldability of High-Strength Stainless Steel for High Pressure Gaseous Hydrogen Environments

2017 ◽  
Vol 86 (8) ◽  
pp. 555-558
Author(s):  
Kana JOTOKU ◽  
Jun NAKAMURA ◽  
Takahiro OSUKI ◽  
Hiroyuki HIRATA
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
High Strength ◽  
Gaseous Hydrogen

scholarly journals Compressibility and Phase Stability of Iron-Rich Ankerite

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 607
Author(s):  
Raquel Chuliá-Jordán ◽  
David Santamaria-Perez ◽  
Javier Ruiz-Fuertes ◽  
Alberto Otero-de-la-Roza ◽  
Catalin Popescu
Keyword(s):  
High Pressure ◽  
Density Functional ◽  
Computational Study ◽  
Density Functional Theory Calculations ◽  
High Pressure Phase ◽  
Stable Phase ◽  
Pressure Derivative ◽  
Reversible Phase Transition ◽  
Murnaghan Equation ◽  
Pressure Phase

The structure of the naturally occurring, iron-rich mineral Ca1.08(6)Mg0.24(2)Fe0.64(4)Mn0.04(1)(CO3)2 ankerite was studied in a joint experimental and computational study. Synchrotron X-ray powder diffraction measurements up to 20 GPa were complemented by density functional theory calculations. The rhombohedral ankerite structure is stable under compression up to 12 GPa. A third-order Birch–Murnaghan equation of state yields V0 = 328.2(3) Å3, bulk modulus B0 = 89(4) GPa, and its first-pressure derivative B’0 = 5.3(8)—values which are in good agreement with those obtained in our calculations for an ideal CaFe(CO3)2 ankerite composition. At 12 GPa, the iron-rich ankerite structure undergoes a reversible phase transition that could be a consequence of increasingly non-hydrostatic conditions above 10 GPa. The high-pressure phase could not be characterized. DFT calculations were used to explore the relative stability of several potential high-pressure phases (dolomite-II-, dolomite-III- and dolomite-V-type structures), and suggest that the dolomite-V phase is the thermodynamically stable phase above 5 GPa. A novel high-pressure polymorph more stable than the dolomite-III-type phase for ideal CaFe(CO3)2 ankerite was also proposed. This high-pressure phase consists of Fe and Ca atoms in sevenfold and ninefold coordination, respectively, while carbonate groups remain in a trigonal planar configuration. This phase could be a candidate structure for dense carbonates in other compositional systems.

Effect of High Pressure Gaseous Hydrogen on the Tensile Properties of Four Types of Stainless Steels: Investigation of Materials Properties in High Pressure Gaseous Hydrogen—1

2007 ◽  
Author(s):  
Hideki Nakagawa
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
Hydrogen Embrittlement ◽  
Storage System ◽  
Gaseous Hydrogen ◽  
Fuel Cell Vehicle ◽  
Ductility Loss ◽  
Hydrogen Storage System ◽  
Type 316L ◽  
Pressure Hydrogen

Practical application of fuel cell vehicle has started in the world, and high-pressure hydrogen tanks are currently considered to be the mainstream hydrogen storage system for commercially implemented fuel cell vehicle. Application of metallic materials to the components of high-pressure hydrogen storage system: hydrogen tanks, valves, measuring instructions and so on, have been discussed. In this work, tensile properties of four types of stainless steels were evaluated in 45MPa (6527psig) and 75MPa (10878psig) high-pressure gaseous hydrogen at a slow strain rate of 3×10−6 s−1 at ambient temperature. Type 316L (UNS S31603) stainless steel hardly showed ductility loss in gaseous hydrogen, since it had stable austenitic structure. On the other hand, Type 304 (UNS S30400) metastable austenitic stainless steel showed remarkable ductility loss in gaseous hydrogen, which was caused by the hydrogen embrittlement of strain induced martensitic phase. Likewise, Type 205 (UNS S20500) nitrogen-strengthened austenitic stainless steel showed remarkable ductility loss in gaseous hydrogen, though it had stable austenitic structure in the same manner as Type 316L. The ductility loss of Type 205 was due to the hydrogen embrittlement of austenitic phase resulting from the formation of planar dislocation array. Furthermore, Type 329J4L (UNS S31260) duplex stainless steel showed extreme ductility loss in gaseous hydrogen, which was caused by the hydrogen embrittlement of ferritic phase.

scholarly journals Effect of the Strain Rate on the Fracture Behaviour of High Pressure Pre-Charged Samples

Proceedings ◽  
2018 ◽  
Vol 2 (23) ◽  
pp. 1417
Author(s):  
Guillermo Álvarez Díaz ◽  
Tomás Eduardo García Suárez ◽  
Cristina. Rodríguez González ◽  
Francisco Javier Belzunce Varela
Keyword(s):  
Fracture Toughness ◽  
High Pressure ◽  
Hydrogen Embrittlement ◽  
Strain Rate ◽  
Fracture Behaviour ◽  
Structural Steels ◽  
Gaseous Hydrogen ◽  
Displacement Rate ◽  
Steel Strength ◽  
Fracture Tests

The aim of this work is to study the effect of the displacement rate on the hydrogen embrittlement of two different structural steels grades used in energetic applications. With this purpose, samples were pre-charged with gaseous hydrogen at 19.5 MPa and 450 °C for 21 h. Then, fracture tests of the pre-charged specimens were performed, using different displacement rates. It is showed that the lower is the displacement rate and the largest is the steel strength, the strongest is the reduction of the fracture toughness due to the presence of internal hydrogen.

scholarly journals Technical Basis for Master Curve for Fatigue Crack Growth of Ferritic Steels in High-Pressure Gaseous Hydrogen in ASME Section VIII-3 Code

2019 ◽  
Author(s):  
Chris San Marchi ◽  
Joseph Ronevich ◽  
Paolo Bortot ◽  
Yoru Wada ◽  
John Felbaum ◽  
...  
Keyword(s):  
High Pressure ◽  
Tensile Strength ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Pressure Vessel ◽  
Master Curve ◽  
Gaseous Hydrogen ◽  
Section Viii ◽  
Crack Growth Rates

Abstract The design of pressure vessels for high-pressure gaseous hydrogen service per ASME Boiler and Pressure Vessel Code Section VIII Division 3 requires measurement of fatigue crack growth rates in situ in gaseous hydrogen at the design pressure. These measurements are challenging and only a few laboratories in the world are equipped to make these measurements, especially in gaseous hydrogen at pressure in excess of 100 MPa. However, sufficient data is now available to show that common pressure vessel steels (e.g., SA-372 and SA-723) show similar fatigue crack growth rates when the maximum applied stress intensity factor is significantly less than the elastic-plastic fracture toughness. Indeed, the measured rates are sufficiently consistent that a master curve for fatigue crack growth in gaseous hydrogen can be established for steels with tensile strength less than 915 MPa. In this overview, published reports of fatigue crack growth rate data in gaseous hydrogen are reviewed. These data are used to formulate a two-part master curve for fatigue crack growth in high-pressure (106 MPa) gaseous hydrogen, following the classic power-law formulation for fatigue crack growth and a term that accounts for the loading ratio (R). The bounds on applicability of the master curve are discussed, including the relationship between hydrogen-assisted fracture and tensile strength of these steels. These data have been used in developing ASME VIII-3 Code Case 2938. Additionally, a phenomenological term for pressure can be added to the master curve and it is shown that the same master curve formulation captures the behavior of pressure vessel and pipeline steels at significantly lower pressure.

Fatigue Crack Growth Behavior of Autofrettaged Hydrogen Pressure Vessel Made of Low Alloy Steel

2017 ◽  
Author(s):  
Yoru Wada ◽  
Yusuke Yanagisawa
Keyword(s):  
High Pressure ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Propagation ◽  
Crack Growth ◽  
Cylindrical Specimen ◽  
Growth Behavior ◽  
Gaseous Hydrogen ◽  
Crack Growth Behavior ◽  
Low Alloy Steel

Autofrettage is used to known as an effective method to prevent fatigue crack propagation of thick-walled cylinder vessels operating under high pressure. Since low-alloy steel shows an enhanced crack growth rate in high-pressure gaseous hydrogen, this paper aims to validate the effect of autofrettage on crack growth behavior in high-pressure gaseous hydrogen utilizing 4%NiCrMoV steel (SA723 Gr3 Class2). An autofrettaged cylindrical specimen with a 70mm inside diameter and 111mm outside diameter was prepared with an axial EDM (depth of 1mm) notched on the inside surface. The measured residual stress profile coincides well with the calculated results. The fatigue crack growth test was conducted by pressurizing the cylinder and varying the external water pressure. Crack propagation from the EDM notch was observed in the non-autofrettaged cylindrical specimen while no crack propagation was observed when the initial EDM notch size was within the compressive residual stress field. When the initial EDM notch size was increased, the fatigue crack growth showed a narrow, groove-like fracture surface for the autofrettaged specimen. In order to qualitatively analyze those results, fatigue crack growth rates were examined under various load ratios including a negative load ratio using a fracture mechanics specimen. From the information obtained, crack growth analysis of an autofrettaged cylinder in a high-pressure hydrogen environment was successfully demonstrated with a fracture mechanics approach.

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