Dynamic Analysis of a Subsea Spool Under Dropped Container Impact Loads

Author(s):  
Zhenhui Liu ◽  
Ragnar Igland ◽  
Sindre Bruaseth ◽  
Luca Ercoli-Malacari

Abstract A rigid subsea spool is used to connect the riser of a jacket platform to oil export pipeline in Johan Sverdrup oil field. The location is within the lifting zones of the platform. Consequently, the dropped object hazard has potential high risk and needs to be checked. This paper presents a numerical model on accessing the structural dynamics of subsea spool under the dropped container impact loads by using de-coupled local and global model. The impact impulse was obtained from local impact analysis by Abaqus Explicit solver, in which deformations from container and pipeline are both captured. The global model was built by using inhouse program utilizing ANSYS APDL macros. A simple input file is only needed for end users. The nonlinear pipe and soil interaction is included in a simplified manner. The model comprises of static and dynamic analysis parts. The static analysis captures the in-place configuration and the functional loads. The dynamic analysis is a restart with inherited stress state from static analysis. The impact impulse was applied by point loads in a certain time range. The nonlinear soil stiffness was approached by spring elements (compression only). The dynamic analysis was done in a longer time, ensuring to capture any dynamic effects. The interface loads at the riser stick-out and riser anchor are both extracted and discussed. Concluding remarks have been made accordingly.


2021 ◽  
Vol 1201 (1) ◽  
pp. 012049
Author(s):  
Z Liu ◽  
R Igland ◽  
S Bruaseth

Abstract Subsea riser tube and spool is often used together to connect the riser of jacket to flowline or pipeline. Due to its limited size (less than 200 m), the location is within the lifting zones of the platform. Consequently, the dropped object hazard has potential high risk and needs to be checked. This paper presents a numerical study on accessing the structural dynamics of a subsea riser connection under the dropped container impact loads. De-coupled local and global models were established. The impact impulse was obtained from local impact analysis by Abaqus Explicit solver, in which deformations from container and pipeline are both captured. The impact energy level is in line with the risk assessment. The global model was built by ANSYS APDL macros. A simple input file is only needed for end users. The nonlinear pipe and soil interaction are included in a simplified manner. The model comprises of static and dynamic analysis parts. The static analysis captures the in-place configuration and the functional loads. The dynamic analysis is a restart with inherited stress state from static analysis. The impact impulse was applied by point loads in a certain time range. The nonlinear soil stiffness was approached by spring elements (compression only). The dynamic analysis was done in a longer time, ensuring to capture any dynamic effects. The interface loads at the riser stick-out and riser anchor are both extracted and discussed. It is shown that present structure design can withstand the dropped loads at the input energy level.



2012 ◽  
Vol 193-194 ◽  
pp. 639-642 ◽  
Author(s):  
Chang Zheng Chen ◽  
Ping Ping Pan ◽  
Shi Wei Zhang ◽  
Meng Qiang

This paper presents static and dynamic analysis of wind turbine towers which is supporting a 1.5MW wind turbine based on the theory of FEM. In static analysis, the modal frequencies of the towers are analyzed without wind load. In dynamic analysis, by the fluid-coupling theory, the dynamic effect of wind loads on the towers is calculated. It can be concluded that the main errors under the different load situations is caused by the impact of fluid structure coupling.



2017 ◽  
Vol 11 (3) ◽  
pp. 15-28 ◽  
Author(s):  
Anjali Kumawat ◽  
Anil Kumar Sharma ◽  
Sunita Kumawat

Android based Smartphones are nowadays getting more popular. While using Smartphone, user is always concerned about security and malicious attacks, cryptographic vulnerability of the applications. With increase in the number of Android mobiles, Android malwares are also increasing very rapidly. So the authors have proposed the “Identification of cryptographic vulnerability and malware detection in Android” system. They have designed a user friendly android application, through which user and developer can easily test the application whether it is benign or vulnerable. The application will be tested firstly using static analysis and then the dynamic analysis will be carried out. The authors have implemented static and dynamic analysis of android application for vulnerable and malicious app detection. They have also created a web page. User can either use the application or the web page.



2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Zhigang Lan

Focused on the utilization of nuclear energy in offshore oil fields, the correspondence between various hazards caused by blowout accidents (including associated, secondary, and derivative hazards) and the initiating events that may lead to accidents of offshore floating nuclear power plant (OFNPP) is established. The risk source, risk characteristics, risk evolution, and risk action mode of blowout accidents in offshore oil fields are summarized and analyzed. The impacts of blowout accident in offshore oil field on OFNPP are comprehensively analyzed, including injection combustion and spilled oil combustion induced by well blowout, drifting and explosion of deflagration vapor clouds formed by well blowouts, seawater pollution caused by blowout oil spills, the toxic gas cloud caused by well blowout, and the impact of mobile fire source formed by a burning oil spill on OFNPP at sea. The preliminary analysis methods and corresponding procedures are established for the impact of blowout accidents on offshore floating nuclear power plants in offshore oil fields, and a calculation example is given in order to further illustrate the methods.



2014 ◽  
Vol 670-671 ◽  
pp. 892-895
Author(s):  
An Ning Zhang ◽  
Yu Ming Gu

This paper studied the difference between the static analysis and dynamic analysis on the mobile refuge chamber. The structure strength static analysis of KJYF96/8 mobile refuge chamber was made by the finite element software SolidWorks Simulation and the stress cloud chart and the displacement cloud chart were obtained. The corresponding relation between the dynamic analysis result and the static analysis result was obtained based on the comparison with the result of the dynamic analysis. The results indicate that the values of the max stress and displacement by static analysis with a uniform external pressure of the dynamic pressure peak value are greater than those by dynamic analysis. And the weighting method of static analysis can be used in the coal mine mobile refuge chamber structure design process instead of dynamic analysis.



Information ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 326 ◽  
Author(s):  
Amr Amin ◽  
Amgad Eldessouki ◽  
Menna Tullah Magdy ◽  
Nouran Abdeen ◽  
Hanan Hindy ◽  
...  

The security of mobile applications has become a major research field which is associated with a lot of challenges. The high rate of developing mobile applications has resulted in less secure applications. This is due to what is called the “rush to release” as defined by Ponemon Institute. Security testing—which is considered one of the main phases of the development life cycle—is either not performed or given minimal time; hence, there is a need for security testing automation. One of the techniques used is Automated Vulnerability Detection. Vulnerability detection is one of the security tests that aims at pinpointing potential security leaks. Fixing those leaks results in protecting smart-phones and tablet mobile device users against attacks. This paper focuses on building a hybrid approach of static and dynamic analysis for detecting the vulnerabilities of Android applications. This approach is capsuled in a usable platform (web application) to make it easy to use for both public users and professional developers. Static analysis, on one hand, performs code analysis. It does not require running the application to detect vulnerabilities. Dynamic analysis, on the other hand, detects the vulnerabilities that are dependent on the run-time behaviour of the application and cannot be detected using static analysis. The model is evaluated against different applications with different security vulnerabilities. Compared with other detection platforms, our model detects information leaks as well as insecure network requests alongside other commonly detected flaws that harm users’ privacy. The code is available through a GitHub repository for public contribution.



Author(s):  
Anjali Kumawat ◽  
Anil Kumar Sharma ◽  
Sunita Kumawat

Android based Smartphones are nowadays getting more popular. While using Smartphone, user is always concerned about security and malicious attacks, cryptographic vulnerability of the applications. With increase in the number of Android mobiles, Android malwares are also increasing very rapidly. So the authors have proposed the “Identification of cryptographic vulnerability and malware detection in Android” system. They have designed a user friendly android application, through which user and developer can easily test the application whether it is benign or vulnerable. The application will be tested firstly using static analysis and then the dynamic analysis will be carried out. The authors have implemented static and dynamic analysis of android application for vulnerable and malicious app detection. They have also created a web page. User can either use the application or the web page.



2014 ◽  
Vol 19 (3) ◽  
pp. 609-619
Author(s):  
C. Kundera ◽  
V.A. Martsinkovsky

Abstract This part of the work presents the design and static analysis of an impeller for a single-stage pump. The impeller is directly connected with a balancing device. The impeller needs to have a properly designed system of longitudinal and lateral clearances on both sides. With the simplifying assumptions concerning the flow and distribution of pressure in the longitudinal and lateral clearances, the static analysis involved deriving relationships between the impeller geometry and the basic performance parameters of the pump. A numerical example was used to show the calculation procedure of static characteristics for the predetermined parameters



Author(s):  
Ahmed H. Elsayed ◽  
Mohamad Husam Helmi

AbstractThis paper examines the effect of geopolitical risk (GPR) on return and volatility dynamics in Middle East and North African (MENA) countries by using an ADCC-GARCH model and a spillover approach. Unlike previous studies, we include the GPR index to capture risk associated with wars, terrorist acts, and political tensions. Moreover, we test for both static and dynamic analysis using a rolling window. In brief, the findings highlight that GPR does not contribute to the return spillovers among MENA financial markets. However, the dynamic analysis provides evidence of the high level of responsiveness of the total spillover index to major political events (e.g., the Arab Spring uprising and political tension between Qatar and other Gulf Cooperation Council countries). More interestingly, Qatar, Kingdom of Saudi Arabia, and the United Arab Emirates are identified as the main transmitters of return spillovers to the rest of the MENA markets. Overall, our results are essential in understanding the impact of the GPR on return spillover among MENA countries, and are of particular importance to policymakers, market regulators, portfolio managers and investors.





Sign in / Sign up

Export Citation Format

Share Document