Loss of Life Estimation using Life Safety Model for Dam Breach Flood Disaster in Malaysia

The need for an emergency disaster management related to dam has risen up in recent years. This is due to uncertainties in global weather predictions which also affect local Malaysian area. With unpredictable prolonged rainy weather, concerns on events that could lead to flooding has triggered the authority to review the evacuation strategies in critical locations. This paper describes an investigation on the effect of early warning system and people response delay to the rate of fatality in the event of flooding due to dam breach. The Life Safety Model is utilized as a tool for the simulation of people vehicle and building response to 2D hydraulic flow of the river originated from the dam. The study area is based on Kenyir Dam and its surrounding vicinity. A number of scenarios are simulated namely cases with and without early warning system. For the case with early warning system, different triggering time is also investigated. On top of that, the effect of people response delay to the warning system is simulated. It was found that early warning system plays a critical role in reducing the number of fatalities due to flooding. Equally important is the time taken for the community to start evacuating when triggered by the early warning system. From the result LSM, optimum evacuation parameters could be identified and used for the purpose of design, planning and implementation of local emergency evacuation plan in the event of dam-related flooding.

A Comprehensive Review of the Dynamic Applications of the Digital Twin Technology Across Diverse Energy Sectors

The energy supply sector, encompassing vital components such as generation, transmission, and distribution, holds a pivotal role in satisfying the energy demands of modern society. Its intricate web of technologies and infrastructure ensures the reliable provision of electricity from diverse fuel sources, bolstering economic advancement and enhancing overall living standards worldwide. In the context of ongoing global energy transitions, the energy sector assumes a critical role in addressing the escalating demand for alternative energy sources and adapting resource allocation strategies to align with evolving societal energy requirements. Nonetheless, the energy supply sector confronts formidable challenges, including infrastructure degradation and grid instability. Not only that, but the demand of energy supply is also expected to rise by 50% by 2050. To counter these issues and enable predictive maintenance and grid optimization, digital twin solutions have emerged as a necessity. This is particularly significant as industry integrates renewable and non-renewable energy sources while managing risks in a dynamic energy landscape that undergoes constant transformation. This paper presents a comprehensive analysis of the myriad applications, benefits, and impediments associated with digital twin technology within the energy supply sector. Employing a methodological framework grounded in systematic reviews, detailed case studies, and extensive data analysis, this review article utilizes illustrative diagrams and visual aids to enhance clarity and comprehension. These pedagogical tools elucidate essential concepts for the deployment of digital twin technology in the energy supply industry. The analysis reveals that 4.81% (35 out of 727) of the reviewed papers explored the application of digital twins in various energy sectors. The review paper yields several significant findings, including a meticulous synthesis of existing literature, an in-depth examination of case studies, an exploration of emerging trends, and the provision of informative visual aids. These collective insights offer a comprehensive grasp of the application and impact of digital twin technology in the energy supply sector

An Offline and Online Approach to the OLTC Condition Monitoring:A Review

Transformer failures have a significant cost impact on the operation of an electrical network. In many utilities, transformers have been operating for many years past their expected usable life. As power demand has surged, transformers in some areas are being loaded beyond their rated capacity to meet the demand. One of the vital components in a transformer is the on-load tap changer (OLTC), which regulates the voltage in the distribution network. This study aims to review several condition-monitoring techniques (online and offline) that can monitor the health of the OLTC and assure the safety of the transformer’s OLTC from irreparable damage by detecting the defect at an earlier stage, which is preceded by the specification of typical faults. This paper also discussed the common faults of the OLTC and the root causes of these faults. The OLTC is prone to mechanical faults due to its frequently changing mechanism in the tap operation. The OLTC are also prone to oil as well as thermal faults. As a result, it is critical to monitor OLTC conditions while they are in use. Proper management of condition monitoring (CM) for the OLTC is useful and necessary to increase availability and achieve optimised operating. Condition monitoring (CM) and diagnostics methods (DM) have been developing since the 1950s. CM and DM have been implemented to diagnose and detect an incipient fault, especially for the OLTC. Many techniques, online and offline, are being used to monitor the condition of the OLTC to prevent failure and minimize outages. These DM and CM will prolong the operational cycle and avoid a major disaster for the OLTC, which is an unfavorable scenario

Thermo-economic analysis of a Coal-Fired Power Plant (CFPP) using turbine cycle heat rate and plant net heat rates at various operating loads

Evaluating Coal-Fired Power Plant (CFPP) performance is a complex process involving the determination of the turbine cycle Heat Rate (TCHR). This study focuses on determining the TCHR by developing a mathematical model. The model, which incorporates economic analysis of the plant, is developed using energy and mass balance relationships of the turbine cycle, validated using plant commissioning data from a 700MWn CFPP located in Perak, Malaysia. Actual plant data from a 700MWn CFPP is utilized to improve the accuracy and increase the confidence of the results of this study. It was found that at the nominal operating load of 729MWg, there is a Heat Rate (HR) deviation of -1,135 kJ/kWh, leading to daily losses of RM240,447 or USD 60,112. Furthermore, it is possible to utilize the developed model at lower loads as the plant is now being used to operate on “cyclic” loads. The daily losses at a lower load of 431MWg are RM125,767 or USD31,442. Thus, the model is able to compare the plant HR at various loads against commissioning data, and economic analysis is able to be carried out effectively. Valuable information for plant operations and performance engineers could be obtained using this model to determine plant HR

Covid-19 effects on students' teaching and learning perspectives in Malaysian varsities

The COVID-19 pandemic has had dramatic effects on the socio-economic and well beings of Malaysians. The objective of the study is to find the effects of the pandemic on university students both on the technical side, such as the sufficiency of infrastructure and the internet to support online teaching and learning (T&L), as well as on the social side, such as stress level and focus on the study. The nationwide study on the effect of the pandemic on Malaysian varsities students was conducted at the end of 2020. There are many important issues uncovered in this study ranging from the technical side, such as internet-ready programs, socio-economic side, to the psychological perspectives. It shall provide invaluable insights to the related ministries while preparing appropriate reactions during the recovery period. The survey revealed that almost 74% of students highlighted that internet coverage and connectivity was the main issue in online T&L. Although statistics show that 90% of Malaysian households have access to the internet, 49% of students reported that their internet connections were poor. The effects of the pandemic are far-reaching, students belonging to the most vulnerable category find themselves in the most non-conducive place to learn, and they are disturbed by siblings. The socio-economics impacts brought about by the pandemic cause ripple effects onto their families. The government distribution of relief aids has lessened the burden of many people, including students; nevertheless, much improvement could be made, especially in the internet facility and coverage

Investigation on Coal Slagging Characteristics and Combustion Behaviour in Furnace

This paper describes an investigation of coal characteristics and slagging potential using coal slagging assessment tool such as numerical slagging indices. Historical data on coal use according to type and shipment in power plant was use for the analysis. It is found that higher content of silica oxide results in higher softening temperature and the monomers modifiers can alter the softening temperature. Calculation also reveals encouraging conditions that could possibly prevent the slagging potential inside the furnace

A Review on Experimental and Numerical Investigations of Jet Impingement Cooling Performance with Nanofluids

Nanofluids offer great potential heat transfer enhancement and provide better thermophysical properties than conventional heat transfer fluids. Application of nanofluids in jet impingement cooling is used for many industrial and scientific purposes as it manages to effectively remove high localized heat. Owing to its tremendous improvement of the heat transfer field, the use of nanofluids in jet impingement cooling has caught the attention of many researchers. This paper reviews previous research and recent advancements of nanofluid jet impingement via both experimental and numerical studies. In experimental approaches, Al2O3-water nanofluids are the most used working fluids by researchers, and most experiments were conducted with conventional impinging jets. As for the numerical approach, the single-phase model was the preferred model over the two-phase model in obtaining numerical solutions, due to the lower computational time required. A deep insight is provided into nanofluid preparation and methods for stabilization. Parameters affecting the performance of the jet impinging system are also investigated with comparison to numerous publications. The main parameters for jet impinging include the jet-to-plate distance (H/D), the shape of the impinged plate (curved, flat or concave), nozzle configurations and the twisted tape ratio. Studies on conventional impinging jets (CIJs), as well as swirling impinging jets (SIJs), are presented in this paper

Effect of Hybrid Nanofluids Concentration and Swirling Flow on Jet Impingement Cooling

Nanofluids have become increasingly salient in heat transfer applications due to their promising properties that can be tailored to meet specific needs. The use of nanofluids in jet impingement flows has piqued the interest of numerous researchers owing to the significant heat transfer enhancement, which is vital in the technological dependence era in every aspect of life, particularly in engineering applications and industry. The aim of this current work is to investigate the effect of hybrid nanofluids concentration and swirling flow on jet impingement cooling through experimental approach. The hybrid nanofluids are prepared through a two-step method and the characterization process is carried out to study the stability and morphological structure of the sample prepared. The prepared hybrid nanofluids are then used as a cooling agent to evaluate the heat transfer performance of jet impinging system. The experimental investigation compares the performance of swirling impinging jets (SIJs) with conventional impinging jets (CIJs) under various jet-to-plate distance (H/D) ratios and nanofluid concentrations. The effects of adding surfactant on nanofluids are also examined. The heat transfer performance of ZnO/water and CuO/water mono-nanofluids are used as comparison to ZnO-CuO/water hybrid nanofluid. The results show that the thermal performance of ZnO-CuO/water hybrid nanofluid is better than that of the mono-nanofluids. Furthermore, as the mass fraction increases, the heat transfer rates improve. The effect of heat transmission by swirling impinging jets is better than that of conventional impinging jets under similar operating conditions. At H/D = 4, Re = 20,000 and hybrid nanofluid concentration at 0.1% under SIJ is observed to have the highest overall Nusselt number