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High‐pressure hydrogen direct injection technology can enable an internal combustion engine to attain high thermal efficiency and discharge clean emissions; hence, the advantages provided by hydrogen jet impingement are crucial. This paper presents an experimental investigation of the high‐pressure hydrogen direct injection from a single‐hole cylindrical injector. A test rig with a spring set was designed based on the impulse conservation law to test important high‐pressure hydrogen jet impingement parameters, such as jet impingement force and impulse. The results show that the hydrogen gas jet exhibits a two‐zone behavior. In Zone I (near‐field dynamic region), the jet impulse is not conservative, and the jet characteristic parameters (jet impingement force and impulse) fluctuate—first decreasing and then increasing. In Zone II, the jet impulse is conservative. This two‐zone jet feature is induced by shockwaves because a high‐pressure hydrogen jet with a high nozzle pressure ratio reaches its sonic speed at the nozzle outlet. The Mach disk height is the inflection point of these two zones. Moreover, the hydrogen injection pressure has a considerable influence on the gas jet. As the injection pressure increases, the hydrogen jet impingement force and impulse increase. Both jet parameters have a linearly increasing relationship with injection pressure. [ABSTRACT FROM AUTHOR]

The coupling of Eulerian and Lagrangian methods in the Eulerian–Lagrangian Spray Atomization (ELSA) approach is critical. This study proposes an equation for the primary breakup particle diameter D of a diesel fuel spray and adopts it as a key transition criterion for coupling. A three-dimensional diesel spray is modeled by the large-eddy simulation (LES) approach. This improved ELSA simulation was conducted using various transition criteria for particle diameter Dcr. The results show that fuel spray experiences two stages: stage I, when a liquid column appears without a dispersed phase, and stage II, when primary breakup occurs with many discrete particles. Although Dcr has little influence on the macro-spray characteristics, such as top penetration distance S and spray cone angle θ, it has significant effects on discrete particles, such as their number, average diameter, distribution and location, and spray cone area. Dcr should be determined on the basis of actual operating conditions. [ABSTRACT FROM AUTHOR]

The Permian mafic dykes of Santanghu Basin offer an opportunity to study the nature of mantle source and tectonic setting of the basin, as well as to provide the theoretical basis for structural transformation of East Junggar region. In this study, zircon U–Pb geochronology, mineral composition analysis, whole‐rock elemental, and Sr‐Nd isotopic geochemistry were conducted to explore the origin and evolution of the primitive magma. LA‐ICPMS zircon U–Pb dating yields ages at 269 Ma. The elemental geochemistry results suggest enrichments in Ba, Pb, and Sr but depletions in Nb, Ta, Zr, and Hf, which indicate that the magma source was influenced by fluid metasomatism. All samples show moderate initial Sr‐Nd isotope results ((87Sr/86Sr)I = 0.704299 to 0.704490 and εNd(t) = +6.16 to +6.83) and have high Sm/Yb ratios, which suggest that the diabases were derived from partial melting of 5%–7% spinel‐garnet Iherzolite lithospheric mantle. Combined with petrological, geochronological data, and the regional tectonic background, it is interpreted that the diabases from Santanghu Basin originated from lithospheric mantle metasomatized by subduction fluids under the background of intracontinental extension. [ABSTRACT FROM AUTHOR]