The flow fields of a blockerless thrust reverser model were studied using computational fluid dynamic (CFD). The numerical simulations were performed with the bypass ratio of 9. The effects of cascade flow ratio and the injection flow ratio with variation of injection parameters at different fan nozzle pressure ratio (FNPR) were studied. According to detailed analysis of the thrust reverser flow characteristics, that the location of secondary injection, slot angle, injection pressure ratio and slot width on the performance of thrust reversers have a great impact. By the investigation, the optimum value of injection parameter can be found.

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Lignin (SCEL) was separated from steam-exploded eucalyptus wood fibers using a supercritical carbon dioxide (scCO2)–ethanol/water composite medium, which was compared with traditional industrial alkaline extraction of lignin (AL) and high-temperature ethanol extraction of lignin (EL). All three kinds of lignin were spray-dried to form microparticles. The obtained SCEL, AL, and EL particles were mixed with poly(vinyl alcohol) (PVOH) to prepare a composite film. Compared with the pure PVOH film, the transmittance of the composite film to ultraviolet light was reduced from more than 70% to less than 20%, and the tensile strengths of the SCEL/PVOH, AL/PVOH, and EL/PVOH films were increased by 79.2%, 39.1%, and 66.0%, respectively. The water contact angle was increased from 35.5° to 95.3°, 59.5°, and 66.7°, respectively. In terms of performance improvement, SCEL had a better effect. The SCEL particle size was small and uniform, and SCEL contained more S-type structural units and β-O-4 bonds, which is conducive to its uniform dispersion in the PVOH matrix and increases the contact area between lignin and ultraviolet light, thereby improving its anti-ultraviolet performance. The hydrophilic groups in lignin form a large number of hydrogen bonds with PVOH, which promotes the combination of lignin and PVOH, and at the same time exposes a large number of hydrophobic groups of lignin, which improves the mechanical properties and the hydrophobicity of the film.