analyzing the vortex-induced vibration of a slender marine structure withlength to diameter ratio up to 200 is the objective of this study. this slender is free to move in both in-line and cross flow directions and immersed completely in water. three different types of shear currents pass on it and cause to vibrate slender in different forms. nowadays, these vibrations are very important for de...

Abstract One of the most serious incidents that can occur in offshore drilling and exploration is damage to well structure subsea components which result uncontrolled hydrocarbon release environment present a safety hazard rig personnel. Over decades, there have been substantial developments mathematical models algorithms used analyze stresses on related define operational integrity windows ope...

When a natural gas pipeline ruptures, the adjacent automatic line control valves (ALCVs) should close quickly to prevent leakage or explosion. The differential pressure set point (DPS) at each valve location is the main criteria for value setting in ALCV action. If the DPS is not properly adjusted, the ALCV may mistakenly close or it may not take any action at proper time. This study focused on...

in this research an algorithm based on monte carlo simulation is introduced to assess the risk of fire following earthquake in residential, industrial, educational, and governmental land-uses in district no. 20 of tehran. the proposed algorithm consist of different modules including hazard analysis, vulnerability assessment, leak and break analysis of damaged pipeline, ignition probability anal...

The coupling effect between the offshore platform and riser in platform-riser multi-body system might be greatly increased under heavy external maritime stresses. will become significantly more nonlinear. partial secondary development of OrcaFlex is carried out considering strong non-linearity dynamic positioning (DP) system, combined with actual construction engineering background lumped mass ...

The fatigue reliability assessment of deepwater risers plays an important role in the safety oil and gas development. Physical-based models are widely used riser analyses. However, these present some disadvantages analyses, such as low computational efficiency inability to introduce inspection data. An improved analysis method was proposed conduct risers. data-driven were established based on r...

The aim of the research was to summarize a mathematical model of bow and arrow interaction in the vertical plane and to develop an appropriated computer model. A bow was modeled as a non-deformed riser and hinged to it two nondeformed limbs with Archimedean springs. Their stiffness as well, as an elasticity of a string was taken into account in a linear approach. An asymmetric bow scheme was co...

FCC riser; Computational fluid dynamics (CFD); Cracking reaction kinetics; Hydrodynamics; 4-Lump kinetic model; k-Epsilon turbulence model Abstract Fluid catalytic cracking (FCC) is an essential process for the conversion of gas oil to gasoline. This study is an effort to model the phenomenon numerically using commercial computational fluid dynamics (CFD) software, heavy density catalyst and 4-...

We investigate three-dimensional problems in solid mechanics with stochastic loading or material properties. To solve these problems, we use a spectral expansion of the solution and random inputs based on Askey-type orthogonal polynomials in terms of independent, identically distributed (i.i.d) random variables. A Galerkin procedure using these types of expansions, the generalized Polynomial Ch...