Research on Collision Response of Titanium Alloy Cylindrical Pressure Shell

Titanium alloy materials are widely used in the marine and aviation fields due to their excellent properties. The submersible sailing on the water surface is faster than underwater diving, so once an accident occurs, the consequences are unimaginable. Based on the failure criterion of the J-K model, this paper uses finite element simulation software to study the impact of impact velocity and impact angle on the collision response of a titanium alloy cylindrical pressure shell, providing a reference for the deep sea titanium alloy pressure shell.

STRESS ANALYSIS OF THICK RING SHELL SUBMITTED TO THE ACTION OF INTERNAL PRESSURE

In this paper. from asymptotic equations of thicking shell obtained on the basis of the equations of three dimensional elastic mechanics using geometric small parameter we find the solutions of the stresses and the deformations of thick ring shell submitted to the action of internal pressure q.

ANALYTICAL SOLUTION OF RADIATED SOUND PRESSURE OF RING－STIFFENED CYLINDRICAL SHELLS IN FLUID MEDIUM

In this paper, analytical formularions of radiated sound pressure of ring-stiffenedcylindrical shells in fluid medium are derived by means of Hamilton's principleHuygens principle and Green function . These formulations Can be used to compute the sound pressure of the shell's surface nearfield and farfield.

Numerical investigation on gas flow heat transfer and pressure drop in the shell side of spiral-wound heat exchangers

As a critical facility,spiral-wound heat exchanger was(SWHE)has the been widely used in many industrial applications.boundary A computational fluid dynamics(CFD)model employed with smallest periodic element results and periodic conditions to examine around the the characteristics tube of the shell side of SWHE.Numerical simulation show that the heat transfer coefficients and initially mean increase absolute and subsequently decrease simulated 5%with heat radial angle because of the influence measured of backflow turbulent separation.nitrogen The deviation between is transfer coefficients and values for methane,drop,ethane,and are a mixture(methane/ethane)within when mean Reynolds number is over is 30000.For the pressure the simulated results values smaller than the measured values,and the absolute on deviation within 9%.Numerical simulation also tubes indicate that the pressure drop the and heat of transfer coefficients angle the shell side and of SWHE heat decrease as the winding the angle of the increases.Nusselt Considering effect winding on pressure drops transfer coefficients,modified correlations of_=0.308Re^(0.64)Pr^(0.36)(1+sin)^(1.38 )and friction factor f_=0.435Re^(-0.133)(sin)^(-0.36),are proposed.Comparing Nu number with the experimental data,the maximum deviations for heat transfer coefficients and pressure drops are less than 5%and11%respectively.

Interior noise field of a viscoelastic cylindrical shell excited by TBL pressure fluctuations:Ⅰ.Production mechanisms of the noise

Applying the wavenumber frequency transfer function to describe the whole system including tht elastic cylindrical shell and the fluid loading, a general expression of the cross spectrum of the interior noise induced by the TBL (turbulent boundary layer) pressure fiuctuations is derived. There are two production mechanisms of the noise: one is direct transfer of the convective ridge of the pressure fluctuations through the shell, the other is the reradiation of resonance modes excited by the pressure fluctuations. At low frequencies the noise produced by the latter mechanism is dominant. Solving the frequency equation of the cylindrical shell with liquid loading, the two Stoneley-type poles in the complex K plane are presented. They are the major sources of the reradiation of shell at low frequencies. Finally, effects of the shell radius, shell thickness, absorption of material and the flow speeds on the noise reduction are computed by numerical iniegration.

Interior noise field of a viscoelastic cylindrical shell excited by TBL pressure fluctuations:Ⅱ. finite hydrophone and array

Finite hydrophone and hydrophone array are the wave vector filter and can re-duce the flow noise. In this paper the responses of the cylindrical area hydrophone and two-circular area hydrophone within viscoelastic cylindrical shell to the TBL (turbulent boundary layer) pressure fluctuations are investigated. Applying the method based on the wavenumber frequency spectrum analysis, the expressions of 1) the noise power spectrum of a single hy-drophone; 2) the space correlation of two hydrophones; 3) the noise power spectrum of array are derived. The dependencies of the noise reduction on hydrophone shape, dimension, element amount and separation of hydrophones of array are calculated by numerical integration. The wide-band and narrow-band correlation for two hydrophones is also calculated. The numerical results show that hydrophone array can effectively reduce the interior noise.