Multiscale Simulation-Based Mixed Train Derailment Analysis: A Case Study

2021 ◽  
Author(s):  
Yi Wang ◽  
Steven Nich ◽  
Kyle Mulligan ◽  
Kevin Oldknow ◽  
G. Gary Wang
Keyword(s):  
Multiscale Simulation ◽  
Operating Conditions ◽  
Dynamics Simulation ◽  
Time Data ◽  
Train Derailment ◽  
Operating Rules ◽  
Sequence Of Events ◽  
Research Initiative ◽  
Rule Changes

Abstract The makeup of mixed-manifest freight trains is often determined through rigid operating rules designed based on steady-state in-train forces under nominal vehicle and track conditions. Despite compliance with these rules, excessive forces experienced during exceptional situations still hold significant potential to result in derailments. This paper presents a case study involving a mixed train derailment in a sharp curve following an undesired brake release. The operating conditions and sequence of events are modelled using a novel multiscale simulation approach to combine industry-established longitudinal and multi-body dynamics simulation packages. The root cause of the derailment in this case study is assessed, along with the effectiveness of subsequent rule changes in mitigating the corresponding risk. The case study and results are further discussed in the broader context of a research initiative to utilize near real-time data collection from wayside and vehicle-mounted measurement systems, together with robust multiscale simulation approaches, to improve the area of mixed train marshalling.

scholarly journals Morwell Coal Mine Fire as a Cascading Disaster: A Case Study

2019 ◽  
Vol 34 (s1) ◽  
pp. s8-s8 ◽  
Author(s):  
Dudley McArdle ◽  
Caroline Spencer ◽  
Frank Archer
Keyword(s):  
Coal Mine ◽  
Core Structure ◽  
Disaster Mitigation ◽  
Alternative View ◽  
Human Society ◽  
Adequate Model ◽  
Mine Fire ◽  
Sequence Of Events ◽  
Coal Mine Fire

Introduction:Despite the influential Hyogo and Sendai Frameworks, risk remains poorly understood in the emergency preparedness sector. Hazard assessment and risk management are usually considered before events. An alternative view considers risk as a cascade of potential consequences throughout an event. The 2014 fire in the Victorian rural community of Morwell included a three-phased event: a small bush fire, from which embers ignited a persistent fire in a disused open cut brown coal mine fire. The consequent air pollution precipitated a public health emergency in the nearby community of 15,000 people.Aim:To examine this event as a case study to investigate concordance with accepted definitions and key elements of a cascading event.Methods:Selected literature informed a risk cascade definition and model as a framework to examine the key post-event public inquiries available in the public domain.Results:Informed by a Conceptual Framework for a Hazard Evolving into a Disaster (Birnbaum et al., 2015), Wong and colleagues promote a Core Structure of a Comprehensive Framework for Disaster Evaluation Typologies (Wong, 2017). This Core Structure provided an adequate model to examine the sequence of events in the Morwell event. Definitions of cascading effects is more complex (Zuccaro et al., 2018). Our analysis of the Morwell event used the authoritative definition of cascading disasters published by Pescaroli and Alexander (2015). Using this definition, the Morwell event increased in progression over time and generated unexpected secondary events of strong impact. The secondary events could be distinguished from the original source of disaster, and demonstrated failures of physical structures as well as inadequacy of disaster mitigation strategies, while highlighting unresolved vulnerabilities in human society.Discussion:The Morwell coal mine fire of 2014 reflects the key criteria of a cascading disaster and provides understandings to mitigate the consequences of similar events in the future.

Innovative real-time sensing of flow dynamics in groundwater and sediments to map contaminant spreading

2021 ◽  
Author(s):  
Goedele Verreydt ◽  
Niels Van Putte ◽  
Timothy De Kleyn ◽  
Joris Cool ◽  
Bino Maiheu
Keyword(s):  
Surface Water ◽  
Groundwater Flow ◽  
Real Time ◽  
Flow Direction ◽  
Flow Dynamics ◽  
Sensor Data ◽  
Time Data ◽  
Mass Fluxes ◽  
First Case

<p>Groundwater dynamics play a crucial role in the spreading of a soil and groundwater contamination. However, there is still a big gap in the understanding of the groundwater flow dynamics. Heterogeneities and dynamics are often underestimated and therefore not taken into account. They are of crucial input for successful management and remediation measures. The bulk of the mass of mass often is transported through only a small layer or section within the aquifer and is in cases of seepage into surface water very dependent to rainfall and occurring tidal effects.</p><p> </p><p>This study contains the use of novel real-time iFLUX sensors to map the groundwater flow dynamics over time. The sensors provide real-time data on groundwater flow rate and flow direction. The sensor probes consist of multiple bidirectional flow sensors that are superimposed. The probes can be installed directly in the subsoil, riverbed or monitoring well. The measurement setup is unique as it can perform measurements every second, ideal to map rapid changing flow conditions. The measurement range is between 0,5 and 500 cm per day.</p><p> </p><p>We will present the measurement principles and technical aspects of the sensor, together with two case studies.</p><p> </p><p>The first case study comprises the installation of iFLUX sensors in 4 different monitoring wells in a chlorinated solvent plume to map on the one hand the flow patterns in the plume, and on the other hand the flow dynamics that are influenced by the nearby popular trees. The foreseen remediation concept here is phytoremediation. The sensors were installed for a period of in total 4 weeks. Measurement frequency was 5 minutes. The flow profiles and time series will be presented together with the determined mass fluxes.</p><p> </p><p>A second case study was performed on behalf of the remediation of a canal riverbed. Due to industrial production of tar and carbon black in the past, the soil and groundwater next to the small canal ‘De Lieve’ in Ghent, Belgium, got contaminated with aliphatic and (poly)aromatic hydrocarbons. The groundwater contaminants migrate to the canal, impact the surface water quality and cause an ecological risk. The seepage flow and mass fluxes of contaminants into the surface water were measured with the novel iFLUX streambed sensors, installed directly in the river sediment. A site conceptual model was drawn and dimensioned based on the sensor data. The remediation concept to tackle the inflowing pollution: a hydraulic conductive reactive mat on the riverbed that makes use of the natural draining function of the waterbody, the adsorption capacity of a natural or secondary adsorbent and a future habitat for micro-organisms that biodegrade contaminants. The reactive mats were successfully installed and based on the mass flux calculations a lifespan of at least 10 years is expected for the adsorption material.  </p>

Move Real-Time Data Analytics to the Cloud: A Case Study on Heron to Dataflow Migration

2021 ◽  
Author(s):  
Huijun Wu ◽  
Xiaoyao Qian ◽  
Aleks Shulman ◽  
Kanishk Karanawat ◽  
Tushar Singh ◽  
...  
Keyword(s):  
Real Time ◽  
Data Analytics ◽  
Time Data ◽  
Real Time Data

A Practical Approach to Expedite a Pore to Process Simulation Model for a Rich Gas Condensate Reservoir – Case Study

2021 ◽  
Author(s):  
Mohamed Ibrahim Mohamed ◽  
Ahmed Mahmoud El-Menoufi ◽  
Eman Abed Ezz El-Regal ◽  
Ahmed Mohamed Ali ◽  
Khaled Mohamed Mansour ◽  
...  
Keyword(s):  
Simulation Model ◽  
Production Optimization ◽  
Operating Conditions ◽  
Gas Condensate ◽  
Western Desert ◽  
Design Parameters ◽  
Compositional Approach ◽  
Process Plant ◽  
Black Oil

Abstract Field development planning of gas condensate fields using numerical simulation has many aspects to consider that may lead to a significant impact on production optimization. An important aspect is to account for the effects of network constraints and process plant operating conditions through an integrated asset model. This model should honor proper representation of the fluid within the reservoir, through the wells and up to the network and facility. Obaiyed is one of the biggest onshore gas field in Egypt, it is a highly heterogeneous gas condensate field located in the western desert of Egypt with more than 100 wells. Three initial condensate gas ratios are existing based on early PVT samples and production testing. The initial CGRs as follows;160, 115 and 42 STB/MMSCF. With continuous pressure depletion, the produced hydrocarbon composition stream changes, causing a deviation between the design parameters and the operating parameters of the equipment within the process plant, resulting in a decrease in the recovery of liquid condensate. Therefore, the facility engineers demand a dynamic update of a detailed composition stream to optimize the system and achieve greater economic value. The best way to obtain this compositional stream is by using a fully compositional integrated asset model. Utilizing a fully compositional model in Obaiyed is challenging, computationally expensive, and impractical, especially during the history match of the reservoir numerical model. In this paper, a case study for Obaiyed field is presented in which we used an alternative integrated asset modeling approach comprising a modified black-oil (MBO) that results in significant timesaving in the full-field reservoir simulation model. We then used a proper de-lumping scheme to convert the modified black oil tables into as many components as required by the surface network and process plant facility. The results of proposed approach are compared with a fully compositional approach for validity check. The results clearly identified the system bottlenecks. The model can be used to propose the best tie-in location of future wells in addition to providing first-pass flow assurance indications throughout the field's life and under different network configurations. The model enabled the facility engineers to keep the conditions of the surface facility within the optimized operating envelope throughout the field's lifetime.

Use of an Integrated Approach for Analysis and Design of Turbocharged Internal Combustion Engine

2021 ◽  
Author(s):  
Thiago Ebel ◽  
Mark Anderson ◽  
Parth Pandya ◽  
Mat Perchanok ◽  
Nick Tiney ◽  
...  
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Early Stage ◽  
Pressure Ratio ◽  
Integrated Approach ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Dynamics Simulation ◽  
Analysis And Design ◽  
Performance Requirements

Abstract When developing a turbocharged internal combustion engine, the choice of turbocharger is usually based on designer experience and existing hardware. However, proper turbocharger design relies on matching the compressor and turbine performance to the engine requirements so that parameters such as boost and back pressure, compressor pressure ratio, and turbine inlet temperatures meet the needs of the engine without exceeding its allowable operating envelope. Therefore, the ultimate measure of a successful turbocharger design is how well it is matched to an engine across various operating conditions. This, in turn, determines whether a new turbocharger is required, or an existing solution can be used. When existing turbocharger solutions are not viable, the engine designer is at a loss on how to define a new turbocharger that meets the desired performance requirements. A common approach in industry has been to scale the performance of an existing turbocharger (compressor and turbine maps) and take these requirements for Original Equipment Manufacturers to possibly match it with a real machine. However, the assumptions made in a basic scaling process are quite simplistic and generally not satisfactory in this situation. A better approach would be to use a validated meanline model for a compressor and turbine instead, allowing to perform an actual preliminary design of such components. Such approach allows to link the engine performance requirements in a very early stage of te component design project and it guides the designer for the design decisions, such as rotor size, variable geometry nozzles, diameter, or shroud trims and others. Therefore, a feasible solution is more likely with design less iterations. This paper describes a methodology for an integrated approach to design and analyze a turbocharged internal combustion engine using commercially available state-of-the-art 1D gas dynamics simulation tool linked to two powerful turbomachinery meanline programs. The outputs of this analysis are detailed performance data of the engine and turbocharger at different engine operating conditions. Two case studies are then presented for a 10-liter diesel truck engine. The first study demonstrates how the programs are used to evaluate an existing engine and reverse engineer an existing turbocharger based only on the available performance maps. Then a second study is done using a similar approach but redesigning a new turbocharger (based on the reverse engineered one) for an increased torque output of the same engine.

Real-Time Thermodynamic Performance Monitoring and Optimum Thermoeconomic Operation of Power Plants

2011 ◽  
Author(s):  
G. Hariharan ◽  
B. Kosanovic
Keyword(s):  
Linear Programming ◽  
Power Plant ◽  
Real Time ◽  
Power Plants ◽  
Operating Conditions ◽  
Recursive Least Squares ◽  
Time Data ◽  
Real Time Data ◽  
One Step ◽  
Inputs And Outputs

The ability of modern power plant data acquisition systems to provide a continuous real-time data feed can be exploited to carry out interesting research studies. In the first part of this study, real-time data from a power plant is used to carry out a comprehensive heat balance calculation. The calculation involves application of the first law of thermodynamics to each powerhouse component. Stoichiometric combustion principles are applied to calculate emissions from fossil fuel consuming components. Exergy analysis is carried out for all components by the combined application of the first and second laws of thermodynamics. In the second part of this study, techniques from the field of System Identification and Linear Programming are brought together in finding thermoeconomically optimum plant operating conditions one step ahead in time. This is done by first using autoregressive models to make short-term predictions of plant inputs and outputs. Then, parameter estimation using recursive least squares is used to determine the relations between the predicted inputs and outputs. The estimated parameters are used in setting up a linear programming problem which is solved using the simplex method. The end result is knowledge of thermoeconomically optimum plant inputs and outputs one step ahead in time.

scholarly journals KAJIAN RELIABILITAS PADA SISTEM SERI-PARALEL DENGAN EMPAT KOMPONEN

2018 ◽  
Vol 7 (1) ◽  
pp. 73-83
Author(s):  
Farhah Izzatul Jannah ◽  
Sudarno Sudarno ◽  
Alan Prahutama
Keyword(s):  
Weibull Distribution ◽  
System Reliability ◽  
Failure Time ◽  
Likelihood Estimation ◽  
Parallel System ◽  
Operating Conditions ◽  
Failure Time Data ◽  
Time Data ◽  
Rank Regression ◽  
Load Resistor

Reliability analysis is the analysis of the possibility that the product or service will function properly for a certain period of time under operating conditions without failure. One configuration of components that can be formed is a series-parallel system on a filter capacitor circuit using 4 components consisting of 2 rectifier diodes, 1 capacitor, and 1 load resistor. The data used to obtain the value of system reliability is the time of failure based on the assumption of failure of the independent component. The function of the form on the system can be expressed by Ф(x)= x1x3 + x1x4 + x2x3 + x2x4 - x1x3x4 - x2x3x4 - x1x2x3 - x1x2x4 + x1x2x3x4. The parameter values of each distribution are calculated using the Median Rank Regression Estimation (MRRE) and Maximum Likelihood Estimation (MLE) methods. To test the data following a certain distribution or not, the calculation is manually done with the Anderson-Darling (AD) test so that it is known that the failure time data of rectifier diode 1 follows the weibull distribution with parameters  and , failure time data of rectifier diode 2 follows weibull distribution with parameters  and , failure time data of capacitors follow normal distribution with parameters  and , and the failure time data of the load resistor following the gamma distribution with parameters  and . From the calculation of system reliability, it shows that the higher the intensity of the system fails it will affect the value of reliability to be lower. A serial system from a parallel system functions if there is at least one component j in one subsystem that functions. Keywords: Reliability, Series-Parallel, MRRE, MLE, AD.

scholarly journals PROFIL FIJAI WARGA BELAJAR PROGRAM KESETARAAN PAKET A SANGGAR KEGIATAN BELAJAR (SKB)

2020 ◽  
Vol 2 (2) ◽  
pp. 111-115
Author(s):  
Putri Mardayani ◽  
Rufran Zulkarnain ◽  
Suardi Jasma
Keyword(s):  
Data Collection ◽  
Qualitative Method ◽  
Family Background ◽  
Traffic Light ◽  
Time Data ◽  
Light Traffic ◽  
Data Presentation ◽  
Traffic Lights ◽  
Data Validity

This study was aimed at describing the profile of Fijai, a student of program kesetaraan paket A Sanggar Kegiatan Belajar of Bengkulu municipality(case study on Fijai who is also a clown). This study used qualitative method. Data collection was done by interview , documentation, and observation. The subjects of this study included Fijai's parents and Fijai's tutor at program kesetaraan paket A Sanggar Kegiatan Belajar of Bengkulu municipality. Data validity was examined using triangulation of subject, technique and time. Data were analyzed through three steps which were data reduction, data presentation, and conclusion drawing. From the results, Fijai's profile was as follows. Firstly, how was Fijai's family background? His parents did not have a job except to help him work as a clown. Fijai got Rp 2,500,000/month from his job as a clown. Secondly, how was his study at program kesetaraan paket A Sanggar Kegiatan Belajar of Bengkulu municipality? He always attended the class once a week. Thirdly,how did he do his job as a clown? He started his job from 10 A.M. until 5 P.M. He moved around while doing his job, sometimes at Suka Merindu traffic light, traffic light near the roundabout, and other traffic lights. Fourthly,how was his parents' response on his education and his job as a clown? His parents agreed with his education at SKB and his job as a clown did not disturb his education. Fively,how was his tutor's response on his education and his job as a clown? According to his tutor he had highly enthusiasm in studying, he always attended the class once a week. Sixly, how was his achievement in package A program? His achievement was increasing per semester. Keywords : The profile of Fijai, student, package A equivalence program

scholarly journals The Differences between Thai and Indonesian Undergraduates in Pronouncing Plural Nouns and Third Singular Present Verbs due to Progressive Assimilation

2016 ◽  
Vol 8 (2) ◽  
pp. 195
Author(s):  
Sofa Zakiyatul Muna
Keyword(s):  
Native Language ◽  
Time Data ◽  
Research Problems ◽  
Learning English

Pronunciation is an important aspect in learning English and it is varied in different area. There are several types of dialect differences in speaking English and geographical dialect is one of them. In pronouncing plural verbs and third singular present verbs in English, the differences are happened. This research investigates the differences between Thai and Indonesian undergraduates in pronouncing plural nouns and third singular present verbs with s/es ending. The aim of this research are to find out the differences and similarities between Thai and Indonesian undergraduates in pronouncing plural nouns and third singular present verbs and the factors that influence it. The design of this research is case study by investigating Thai and Indonesian undergraduates of IAIN Salatiga in several period of time. Data is collected through documentation and interview. Documentation is conducted by recording respondents’ pronunciation. The recording is analyzed and combined with interview report to answer research problems. From the analysis, it is found that the differences and similarities of Thai and Indonesian undergraduates are substitution and omission of s/es suffix pronunciation. It is influenced by the geographic dialects and the existence of consonants in native language. 

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