failure conditions
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Machines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 51
Author(s):  
Rong Xie ◽  
Weihuang Liu ◽  
Muyan Chen ◽  
Yanjun Shi

Integrated energy system (IES) is an important direction for the future development of the energy industry, and the stable operation of the IES can ensure heat and power supply. This study established an integrated system composed of an IES and advanced adiabatic compressed air energy storage (AA-CAES) to guarantee the robust operation of the IES under failure conditions. Firstly, a robust operation method using the AA-CAES is formulated to ensure the stable operation of the IES. The method splits the energy release process of the AA-CAES into two parts: a heat-ensuring part and a power-ensuring part. The heat-ensuring part uses the high-temp tank to maintain the balance of the heat subnet of the IES, and the power-ensuring part uses the air turbine of the first stage to maintain the balance of the power subnet. Moreover, another operation method using a spare gas boiler is formulated to compare the income of the IES with two different methods under failure conditions. The results showed that the AA-CAES could guarantee the balance of heat subnet and power subnet under steady conditions, and the dynamic operation income of the IES with the AA-CAES method was a bit higher than the income of the IES with the spare gas boiler method.


Icarus ◽  
2022 ◽  
Vol 371 ◽  
pp. 114700
Author(s):  
Liliane M.L. Burkhard ◽  
Bridget R. Smith-Konter ◽  
Sarah A. Fagents ◽  
Marissa E. Cameron ◽  
Geoffrey C. Collins ◽  
...  

2021 ◽  
Author(s):  
◽  
Bradley Mark Cosgrove

<p>Recent landslides from Wellington fill slopes have occurred as potentially hazardous, mobile debris flow-slides with long runouts during heavy rainstorms. Globally, catastrophic landslides from fill slopes are well documented, and in many instances their rapid failure and long runout suggests that their shear zones may be subject to liquefaction. Various generations of fill slopes throughout Wellington, and urban New Zealand, have been constructed using different practices and at variable scales. Despite this, very few laboratory based studies to determine how different fill slopes may perform during rainstorms have been attempted, as conventional laboratory tests do not adequately simulate the failure conditions in the slope.  This study uses a novel, dynamic back-pressured shear box to conduct rapid shear and specialist pore pressure inflation tests in order to replicate rainfall induced failure conditions in fill slopes with different consolidation histories and particle size characteristics. During each test, excess pore-water pressures and deformation were monitored until failure in order to determine the failure mechanisms operating.  This study demonstrates that the failure mechanisms in fill slopes are strongly influenced by the consolidation history and particle size characteristics of the shear zone materials. In over-consolidated and fine grained (< 0.4 mm) fills where cohesion is present, brittle failure was observed. In these materials, failures occur more rapidly but require much higher pore-water pressures to initiate. Conversely, normally-consolidated fill slopes constructed from coarser material (0.4 - 2 mm) fail through ductile deformation processes, which typically initiate at much lower pore-water pressures but result in a less rapid slope failure. Although liquefaction was not observed, excess pore-water pressures can be generated during rapid shearing, indicating that liquefaction could occur after a landslide has initiated in conditions where excess pore-water pressures are unable to dissipate away from the shear zone. These results provide new insights into the types of failure that may be anticipated from different fill slopes, the hazards they may pose and potential mitigation measures that could be implemented.</p>


2021 ◽  
Author(s):  
◽  
Bradley Mark Cosgrove

<p>Recent landslides from Wellington fill slopes have occurred as potentially hazardous, mobile debris flow-slides with long runouts during heavy rainstorms. Globally, catastrophic landslides from fill slopes are well documented, and in many instances their rapid failure and long runout suggests that their shear zones may be subject to liquefaction. Various generations of fill slopes throughout Wellington, and urban New Zealand, have been constructed using different practices and at variable scales. Despite this, very few laboratory based studies to determine how different fill slopes may perform during rainstorms have been attempted, as conventional laboratory tests do not adequately simulate the failure conditions in the slope.  This study uses a novel, dynamic back-pressured shear box to conduct rapid shear and specialist pore pressure inflation tests in order to replicate rainfall induced failure conditions in fill slopes with different consolidation histories and particle size characteristics. During each test, excess pore-water pressures and deformation were monitored until failure in order to determine the failure mechanisms operating.  This study demonstrates that the failure mechanisms in fill slopes are strongly influenced by the consolidation history and particle size characteristics of the shear zone materials. In over-consolidated and fine grained (< 0.4 mm) fills where cohesion is present, brittle failure was observed. In these materials, failures occur more rapidly but require much higher pore-water pressures to initiate. Conversely, normally-consolidated fill slopes constructed from coarser material (0.4 - 2 mm) fail through ductile deformation processes, which typically initiate at much lower pore-water pressures but result in a less rapid slope failure. Although liquefaction was not observed, excess pore-water pressures can be generated during rapid shearing, indicating that liquefaction could occur after a landslide has initiated in conditions where excess pore-water pressures are unable to dissipate away from the shear zone. These results provide new insights into the types of failure that may be anticipated from different fill slopes, the hazards they may pose and potential mitigation measures that could be implemented.</p>


Author(s):  
Rakshitha Ravi ◽  
USHA SURENDRA

Here this document provides the data about the batteries of electric vehicles. It consists of numerous data about various energy storage methods in EVs and how it is different from energy storage of IC-engine vehicles. How electric vehicles will take over ICEngine vehicles due to advancement in battery technology and the shrink in its prices. Various types of batteries are listed in the document with their specifications. Possible future battery technology which will have more or same energy density than current gasoline fuels and also with the significant reduction in battery weights; which will make EVs cheaper than current condition. Some examples are listed showing current battery capacities of various EVs models. Some battery parameters are shown in the document with introduction to BMS (Battery Management System). Then a brief introduction about the charging of these EV batteries and its types displaying variations in charging time in different types of EVs according to their charger type and manufacturers. How DC charging is more time saving method than AC and how smart charging will help to grid in case of peak or grid failure conditions.


2021 ◽  
Author(s):  
Christian Windisch

Abstract This paper presents a holistic approach to modern oilfield and well surveillance through the inclusion of state-of-the-art edge computing applications in combination with a novel type of data transmission technology and algorithms developed in-house for automatic condition monitoring of SRP systems. The objective is to enable the responsible specialist staff to focus on the most important decisions regarding oilfield management, rather than wasting time with data collection and preparation. An own operated data communication system, based on LPWAN-technology transfers the dyno-cards, generated by an electric load cell, into the in-house developed production assistance software platform. Suitable programmed AI-algorithms enable automatic condition detection of the incoming dyno cards, including conversion and analysis of the corresponding subsurface dynamograms. A smart alarming system informs about occurring failure conditions and specifies whether an incident of rod rupture, pump-off condition, gas lock or paraffin precipitation occurred in the well. A surface mounted measuring device delivers liquid level and bottomhole pressure information automatically into the software. Based on these diverse data, the operations team plans the subsequent activities. The holistic application approach is illustrated using the case study of an SPR-operated well in an Austrian brownfield.


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Zhengyuan Xin ◽  
Qingliang Zeng ◽  
Yang Yang

In top coal caving mining, common impact occurs between coal gangue particles and tail beam. Little attention has been paid to the effects of coal gangue particles failure on impact force and tail beam response theoretically, numerically, and experimentally. This paper aims to reveal the influence of coal gangue particles failure on the impact effect of tail beam. First, this paper incorporates the theory of rock failure and energy consumption to assess the impact process of coal gangue particles on the tail beam. A new model to simulate the actual failure conditions of rock particles was developed: the brittle damage-fracture particle model. By comparing damage phenomena and simulation data, the brittle damage-fracture particle model was proved to be correct. Based on this model, a dynamic simulation of brittle coal gangue particles impacting the tail beam was conducted. Then, the dynamic responses of the particles and tail beam were analyzed. The results show that particle failure significantly affects the impact force and dynamic response of the tail beam. The impact effects of coal and gangue particles on the tail beam and their failure energy consumption also differed significantly. This paper stresses the importance of coal gangue particle failure conditions for research on top coal caving mining. Theoretical support is provided for the research of coal gangue identification technology based on the tail beam vibration signal.


2021 ◽  
Vol 13 (22) ◽  
pp. 12868
Author(s):  
Umer Zaman ◽  
Laura Florez-Perez ◽  
Pablo Farías ◽  
Saba Abbasi ◽  
Muddasar Ghani Khwaja ◽  
...  

Globally, demands for sustainable strategies in the ICT industry have attracted greater momentum as high-tech projects continue to fail in large numbers. Recent studies have underpinned project resilience as a major factor for overcoming these increasing project failures, delays, or termination. However, the complex behaviors of resilient project leaders, especially in post-failure conditions, have been largely overlooked. To address this critical research gap, the present study identifies the direct relationships between three potential behavioral traits of project leaders (i.e., resilience, self-esteem, and self-efficacy) and examines how they move forward beyond project failures. The present study also explored whether self-esteem mediates project leaders’ resilience and self-efficacy. Drawing on data from 232 project leaders in Pakistan’s high-tech start-ups, the new findings suggest that there are significant positive effects of project leaders’ resilience and self-esteem on their self-efficacy, and that project leaders’ resilience and self-efficacy is significantly mediated by their self-esteem. As the project resilience theory gains traction, the present study findings have pinpointed major steps for meeting project challenges ahead of time, allowing leaders and teams to learn from failures, and also for improving organisations’ ability to implement successful and sustainable high-tech projects especially in emerging economies.


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