Oxygen gas-liquid mass transfer coefficient was measured in a gas-induced pulsating flow bubble column. Pulsating amplitude had a great influence on kla under pulsating state of equal base flow and pulsating flow, which was enhanced up to 30 % compared with that under steady state; however, it had a negative effect on mass transfer under a fixed low base flow. It was also found that kla had a n...

In this paper, we prove the uniqueness, up to shifts, of pulsating traveling fronts for reaction-diffusion equations in periodic media with Kolmogorov-Petrovsky-Piskunov type nonlinearities. These results provide in particular a complete classification of all KPP pulsating fronts. Furthermore, in the more general case of monostable nonlinearities, we also derive several global stability propert...

For the purpose of eliminating annular welding seams in structures with differential thickness, a hydroforming method using circular 5A06 aluminum alloy plate radial thickness coupling flexible polyurethane auxiliary was proposed to form an integrated semi-ellipsoid shell. The had smaller middle and larger periphery. In forming process such plates, concentrated deformation fracture might have o...

Motivated by recent event studies and modeling efforts on pulsating aurora, which conclude that the precipitation energy during these events is high enough to cause significant chemical changes in the mesosphere, this study looks for the bulk behavior of auroral pulsations. Based on about 400 pulsating aurora events, we outline the typical duration, geomagnetic conditions, and change in the pea...

This study aims to investigate the formability of AA2198-T3 Al-Li alloy in hydro-mechanical deep drawing (HMDD), through experimentation and finite element simulation. The effects most critical factors were studied: die cavity pressure forming temperature; temperature is selected at 298K 423K. Gurson?Tvergaard?Needleman model (GTN model) was employed analyze predict fracture hydroforming a cyli...

Product design in the early stages requires a more quantitative process to ensure that simulation study's outcome will meet expectations. The purpose of this study was determine whether manufacturing software package could effectively evaluate and validate conceptualised blank tooling manufacture sizeable complex- shaped aluminium alloy aircraft panel using die sheet hydroforming. Blank tool co...

This paper presents a control model of the hydroforming and the dual hydroforming process of a tube. The theoretical part includes calculations to measure the change in tube thickness through the developed process. The hydroforming and the dual hydroforming processes are simulated in the SOLIDSIMULATION software and the static and the dynamic simulations are modeled. The obtained results for th...