We attempt to study the characteristics of the different stellar populations present in the Galactic central region. A Monte Carlo method is used to simultaneously fit 11 thin disc and triaxial outer bulge density parameters on (Ks, J-Ks) star count data in almost 100 windows from the DENIS near infrared large scale survey at-8 • <l<12 • and |b|<4 •. Various bulge density profiles and luminosit...

The internal hydroforming of large stainless-steel eggshells from a stepped preform is investigated in this paper. nominal major and minor axes the eggshell were 1537 1070 mm, respectively. was fabricated thin-walled (1.9 mm thick) sheets comprised twelve conical segments inscribed inside target eggshell. then hydroformed, its wall thickness shape measured. yield load distribution material hard...

In ultrasonic tube hydroforming, the tube is hydro formed while the ultrasonic vibration is applied to the die. Prior studies provide experimental proof that ultrasonic tube hydroforming reduces corner radius, improves lubrication and uniform thickness. Use of ultrasonic vibration can decrease friction at the tube-die interface. Few attempts have been made to analyze the wire drawing while the ...

In this paper, hydroforming process of bent tubes in T-shaped die is studied for pulsating and linear pressure paths by the finite element method. Forming Limit Diagrams (FLDs) and thickness distribution curves are used to investigate the effect of pulsating pressure on hydroforming process. In addition, the obtained numerical results are compared with experimental results of hydroforming of st...

The investigation into the circumferential mechanical properties of tubular materials has been receiving increasing attention, since tube hydroforming process used in forming field, because have a significant effect on hydroformability materials. In present study, method for evaluation with flaring test was proposed. expressions yield stress, strain hardening coefficient and exponent values wer...

Hydroforming processes of metal tubes and sheets are being widely applied in manufacturing because the increasing demand for lightweight parts sectors such as automobile, aerospace, ship-building industries [...]

this paper presents a control model of the hydroforming and the dual hydroforming process of atube. the theoretical part includes calculations to measure the change in tube thickness through thedeveloped process. the hydroforming and the dual hydroforming processes are simulated in thesolidsimulation software and the static and the dynamic simulations are modeled. theobtained results for the t-...