An Interactive Expert System Based Decision Making Model for the Management of Transit System Alternate Fuel Vehicle Assets

Traditionally, the process used by public transportation entities to determine the acquisition strategy for new vehicle asset is based upon a broad range of criteria. Vehicle cost has been cited as one of the more critical factors which decision makers consider. It is currently a common practice to consider other factors (life-cycle cost, fuel efficiency, vehicle reliability, environmental effects, etc.) that contribute to a more comprehensive approach. This study investigates the next generation of advancements in decision making tools in the area of the application of methods to quantify and manage uncertainty. In particular, the uncertainty comes from the public policy arena where future policy and regulations are not always based upon logical and predictable processes. The fleet decision making process in most governmental agencies is a very complex and interdependent activity. There are always competing forces and agendas within the view of the decision maker. Rarely is the decision maker a single person although, within the transit environment, there is often one person charged with the responsibility of fleet management. The focus of this research examines the decision making of the general transit agency community via the development of an expert systems prototype tool. A computer-based prototype system is developed which provide an expert knowledge-based recommendation, based upon variable user inputs. The results shown in this study show that a decision making tool for the management of transit system alternate fuel vehicle assets can be modeled and tested. The direct users of this research are the transit agency administrations. The results can be used by the management teams as a reliable input to inform their urban transit buses expansion decision making process.

Patterned catalyst layer boosts the performance of proton exchange membrane fuel cells by optimizing water management

Mass transport is crucial to the performance of proton exchange membrane fuel cells,especially at high current densities.Generally,the oxygen and the generated water share same transmission medium but move towards opposite direction,which leads to serious mass transfer problems.Herein,a series of patterned catalyst layer were prepared with a simple one-step impressing method using nylon sieves as templates.With grooves 100μm in width and 8μm in depth on the surface of cathode catalyst layer,the maximum power density of fuel cell increases by 10%without any additional durability loss while maintaining a similar electrochemical surface area.The concentration contours calculated by finite element analysis reveal that the grooves built on the surface of catalyst layer serve to accumulate the water nearby while oxygen tends to transfer through relatively convex region,which results from capillary pressure difference caused by the pore structure difference between the two regions.The separation of oxidant gas and generated water avoids mass confliction thus boosts mass transport efficiency.

Energy management strategy based on dynamic programming with durability extension for fuel cell hybrid tramway

This paper proposes an energy management strategy for a fuel cell(FC)hybrid power system based on dynamic programming and state machine strategy,which takes into account the durability of the FC and the hydrogen consumption of the system.The strategy first uses the principle of dynamic programming to solve the optimal power distribution between the FC and supercapacitor(SC),and then uses the optimization results of dynamic programming to update the threshold values in each state of the finite state machine to realize real-time management of the output power of the FC and SC.An FC/SC hybrid tramway simulation platform is established based on RTLAB real-time simulator.The compared results verify that the proposed EMS can improve the durability of the FC,increase its working time in the high-efficiency range,effectively reduce the hydrogen consumption,and keep the state of charge in an ideal range.

Aviation Fuel System Safety Management Analysis

The development of China’s aviation industry is accelerating,especially in terms of national political protection,military security and economic security.In the aviation industry’s aviation fuel system management,safety management is an important content.This paper focuses on the safety management of aviation fuel systems.

Development of core fuel management code system for WWER-type reactors

In this article, a core fuel management program for hexagonal pressurized water type WWER reactors (CFMHEX) has been developed, which is based on advanced three-dimensional nodal method and integrated with thermal hydraulic code to realize the coupling of neutronics and thermal-hydraulics. In CFMHEX, all these feedback effects such as burnup, power distribution, moderator density, and control rod insertion are considered. The verifica- tion and validation of the code system have been examined through the IAEA WWER-1000-type Kalinin NPP benchmark problem. The numerical results are in good agreement with measurements and are close to those of other international institutes.

Application Model of Energy Management and Emissions Control to Limit Environmental Risks of Fossil Fuel

Around the world energy sustainability and environment protection face many challenges due to the continuously increasing population and energy demands, where the demanding rate of energy increases by at least 2.3% per year. According to statistical data, until 2035, fossil fuels still are the main source of energy consumption. Burning fossil fuels produces the greenhouse gas of carbon dioxide as a byproduct. CO2 emissions have a dangerous effect on both human health and the natural environmental balance. There are many types of clean energy like solar, biofuel, and wind energy. The major limitations of using these types, their availability depends on climate conditions and their production rate is inadequate for energy demand. For any country, energy resources’ availability and economic conditions imposed on projects’ prioritization. Application of energy management and emissions control techniques for industrial unit can limit fuel combustion environmental effects and transfer this fossil fuel to an eco-friendly type. In this work, we applied Green Energy Model GEM to the Hydrotreater Unit of the refinery, GEM is composed of four techniques. Which are Heat Exchangers Networks Synthesis [HENS], Fuel Switching, Thermal Insulation application, and Carbon Captures Storage [CCS]. Where they reduce energy consumption by the rate of 3% - 34% and control CO2 emissions by the rate of 26% - 90%. This model is a radical way to face climate change challenges and practical solutions for both energy and environmental crises.

An optimal energy management development for various configuration of plug-in and hybrid electric vehicle

Due to soaring fuel prices and environmental concerns, hybrid electric vehicle(HEV) technology attracts more attentions in last decade. Energy management system, configuration of HEV and traffic conditions are the main factors which affect HEV's fuel consumption, emission and performance. Therefore, optimal management of the energy components is a key element for the success of a HEV. An optimal energy management system is developed for HEV based on genetic algorithm. Then, different powertrain system component combinations effects are investigated in various driving cycles. HEV simulation results are compared for default rule-based, fuzzy and GA-fuzzy controllers by using ADVISOR. The results indicate the effectiveness of proposed optimal controller over real world driving cycles. Also, an optimal powertrain configuration to improve fuel consumption and emission efficiency is proposed for each driving condition. Finally, the effects of batteries in initial state of charge and hybridization factor are investigated on HEV performance to evaluate fuel consumption and emissions. Fuel consumption average reduction of about 14% is obtained for optimal configuration data in contrast to default configuration. Also results indicate that proposed controller has reduced emission of about 10% in various traffic conditions.

Energy Management Control StraEnergy Management Control Strategy for Renewable Energy System Based on Spotted Hyena Optimizertegy for Renewable Energy System Based on Spotted Hyena Optimizer

Hydrocarbons,carbon monoxide and other pollutants from the transportation sector harm human health in many ways.Fuel cell(FC)has been evolving rapidly over the past two decades due to its efficient mechanism to transform the chemical energy in hydrogen-rich compounds into electrical energy.The main drawback of the standalone FC is its slow dynamic response and its inability to supply rapid variations in the load demand.Therefore,adding energy storage systems is necessary.However,to manage and distribute the power-sharing among the hybrid proton exchange membrane(PEM)fuel cell(FC),battery storage(BS),and supercapacitor(SC),an energy management strategy(EMS)is essential.In this research work,an optimal EMS based on a spotted hyena optimizer(SHO)for hybrid PEM fuel cell/BS/SC is proposed.The main goal of an EMS is to improve the performance of hybrid FC/BS/SC and to reduce the amount of hydrogen consumption.To prove the superiority of the SHO method,the obtained results are compared with the chimp optimizer(CO),the artificial ecosystem-based optimizer(AEO),the seagull optimization algorithm(SOA),the sooty tern optimization algorithm(STOA),and the coyote optimization algorithm(COA).Two main metrics are used as a benchmark for the comparison:the minimum consumed hydrogen and the efficiency of the system.The main findings confirm that the minimum amount of hydrogen consumption and maximum efficiency are achieved by the proposed SHO based EMS.

Development of Hybrid Propulsion System for Energy Management and Emission Reduction in Maritime Transport System

Given the strategic importance of energy and air pollution in the today world and due to the fact that the maritime transport system is one of the main sources of energy consumption and emissions in the environment, particularly contamination of water, so in recent years, fuel consumption and emissions reduction in the maritime transport industry has received considerable attention. Thus, in this paper, a new method is provided for typical boat hybridization, so by adding an electric motor and battery to boat power transmission system, dynamic performance will improve fuel consumption and emissions reduces. For this purpose, power transmission system elements are modelled and boat function is evaluated in real terms of movement by defining energy management strategy between power sources. The simulation results show that boat hybridization considerably reduces fuel consumption and emissions.

Satellite remote-sensing technologies used in forest fire management

Satellite remote sensing has become a primary data source for fire danger rating prediction, fuel and fire mapping, fire monitoring, and fire ecology research. This paper summarizes the research achievements in these research fields, and discusses the future trend in the use of satellite remote-sensing techniques in wildfire management. Fuel-type maps from remote-sensing data can now be produced at spatial and temporal scales quite adequate for operational fire management applications. US National Oceanic and Atmospheric Administration (NOAA) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellites are being used for fire detection worldwide due to their high temporal resolution and ability to detect fires in remote regions. Results can be quickly presented on many Websites providing a valuable service readily available to fire agency. As cost-effective tools, satellite remote-sensing techniques play an important role in fire mapping. Improved remote-sensing techniques have the potential to date older fire scars and provide estimates of burn severity. Satellite remote sensing is well suited to assessing the extent of biomass burning, a prerequisite for estimating emissions at regional and global scales, which are needed for better understanding the effects of fire on climate change. The types of satellites used in fire research are also discussed in the paper. Suggestions on what remote-sensing efforts should be completed in China to modernize fire management technology in this country are given.

Pore-Scale Investigation of Coupled Two-Phase and Reactive Transport in the Cathode Electrode of Proton Exchange Membrane Fuel Cells

A three-dimensional multicomponent multiphase lattice Boltzmann model(LBM)is established to model the coupled two-phase and reactive transport phenomena in the cathode electrode of proton exchange membrane fuel cells.The gas diff usion layer(GDL)and microporous layer(MPL)are stochastically reconstructed with the inside dynamic distribution of oxygen and liquid water resolved,and the catalyst layer is simplifi ed as a superthin layer to address the electrochemical reaction,which provides a clear description of the fl ooding eff ect on mass transport and performance.Diff erent kinds of electrodes are reconstructed to determine the optimum porosity and structure design of the GDL and MPL by comparing the transport resistance and per-formance under the fl ooding condition.The simulation results show that gradient porosity GDL helps to increase the reactive area and average concentration under fl ooding.The presence of the MPL ensures the oxygen transport space and reaction area because liquid water cannot transport through micropores.Moreover,the MPL helps in the uniform distribution of oxygen for an effi cient in-plane transport capacity.Crack and perforation structures can accelerate the water transport in the assembly.The systematic perforation design yields the best performance under fl ooding by separating the transport of liquid water and oxygen.

Analysis of Forest Waste Management and Recycling Potential in Nigeria

Forest wastes are renewable resources that can serve as sources of energy for heat and electricity generation. How these materials are managed in order to reduce their contribution to the release of greenhouse gases, reduce subsequent climate change challenges and their potential use in bio-energy production has remained a myth in Nigeria. In this paper, extensive review of the literature was carried out to arrive at the findings. More than 93% of all wood processing industries in Nigeria are sawmills. In addition to sawmills there are the plywood mills, furniture processing industries, and particleboard mills. Sawdust is the major waste generated from wood processing in the various processing units. Currently, the most popular waste management practice in Nigeria is burning. Dumping in open spaces, riverbanks, and water bodies is also obtainable. There is no record of wood waste recycling for bio-fuel production at the moment. Wood wastes are reused for agricultural production (mulching, manure) and as firewood. These actions contribute to the release of greenhouse gases and subsequently contribute to global warming. There are policies and agencies put in place to address this menace but implementation is a problem. An increase in proper waste management education and awareness, and aid from developed countries in terms of providing the technology needed for recycling and incineration, will go a long way in ensuring the safety (from climate change and consequences) of the local people, the environment, and the world at large.

融合工况预测的燃料电池汽车里程自适应等效氢耗最小控制策略

为有效地提高插电式燃料电池汽车的经济性,实现燃料电池和动力电池的功率最优分配,考虑到行驶工况、电池荷电状态(State of charge,SOC)、等效因子与氢气消耗之间的密切联系,制定融合工况预测的里程自适应等效氢耗最小策略.通过基于误差反向传播的神经网络来实现未来短期车速的预测,分析未来车辆需求功率变化,同时借助全球定位系统规划一条通往目的地的路径,智能交通系统便可获取整个行程的交通流量信息,利用行驶里程和SOC实时动态修正等效消耗最小策略中的等效因子,实现能量管理策略的自适应性.基于MATLAB/Simulink软件,搭建整车仿真模型与传统的能量管理策略进行仿真对比验证.仿真结果表明,采用基于神经网络的工况预测算法能够较好地预测未来短期工况,其预测精度相较于马尔可夫方法提高12.5%,所提出的能量管理策略在城市道路循环工况(UDDS)下的氢气消耗比电量消耗维持(CD/CS)策略下降55.6%.硬件在环试验表明,在市郊循环工况(EUDC)下的氢气消耗比CD/CS策略下降26.8%,仿真验证结果表明了所提出的策略相比于CD/CS策略在氢气消耗方面的优越性能,并通过硬件在环实验验证了所提策略的有效性.

基于蜂窝仿生流场的质子交换膜燃料电池的性能研究及优化

为了增强质子交换膜燃料电池(PEMFCs)内部燃料分布的均匀性与水管理能力,本文研究了一种新型的基于仿生结构的蜂窝仿生流场。首先,根据蜂窝结构特征,搭建出三维多相流非等温几何模型并确立PEMFC的数学模型;其次,采用计算流体动力学Fluent软件对模型进行无关性与有效性验证,并对蜂窝仿生流场和常规平行流场的电池性能和燃料分布进行了模拟分析;最后,对比极化性能、气体流速分布、燃料与液态水组分浓度和电流密度分布,验证了蜂窝仿生流场设计的有效性。研究结果表明:采用蜂窝仿生流场的电池峰值功率密度比常规平行流场高15.6%,其内部水管理能力和燃料分布均匀性均强于平行流场;左端进气的蜂窝仿生流场比采用上端进气的蜂窝仿生流场在气体通路内具有更均匀的气体压力,可有效避免流道内产生局部涡流,其峰值功率密度可以达到0.3933 W/cm2。

质子交换膜燃料电池热管理系统建模及故障仿真

文章以质子交换膜燃料电池(Proton Exchange Membrane Fuel Cell,PEMFC)系统为研究对象,分析系统中各组成部件的工作机理,在MATLAB/Simulink软件中搭建了燃料电池电堆电压、阴极、质子交换膜、阳极以及温度的数学机理模型,同时使用Simulink/Simscape物理建模平台搭建热管理系统的物理模型,将两种模型集成为完整的PEMFC系统仿真模型。在所搭建的热管理系统模型中注入典型故障:散热器风扇故障和冷却液流量不足故障,对各故障模式下的燃料电池性能进行了分析。仿真结果表明:PEMFC系统模型结果与试验结果基本一致,验证了模型的合理性;通过对热管理系统故障进行仿真,可以清楚地了解故障发生的机理,为其故障诊断提供了参考依据。

基于近端策略优化算法的燃料电池混合动力系统综合价值损耗最小能量管理方法

为了降低市域动车组燃料电池混合动力系统运行燃料经济成本,提升燃料电池耐久性,该文提出一种基于近端策略优化算法的能量管理方法。该方法将混合动力系统能量管理问题建模为马尔可夫决策过程,以综合考虑燃料经济性和燃料电池耐久性的综合价值损耗最小为优化目标设置奖励函数,采用一种收敛速度较快的深度强化学习算法—近端策略优化算法求解,实现负载功率在燃料电池和锂电池间的合理有效分配,最后,采用市域动车组实际运行工况进行实验验证。实验结果表明,在训练工况下,所提方法相较基于等效氢耗最小能量管理方法和基于Q-learning能量管理方法,综合价值损耗分别降低19.71%和5.87%;在未知工况下,综合价值损耗分别降低18.05%和13.52%。结果表明,所提方法能够有效降低综合价值损耗,并具有较好的工况适应性。

燃料电池增程式动力系统能量管理策略研究

以某款纯电动客车为研究对象,以增加车辆续驶里程为目的,提出燃料电池增程式混合动力系统结构,根据性能指标对动力系统各部件进行匹配计算和选型.提出了开关/功率跟随式能量管理策略,基于Cruise和Simulink分别搭建了整车动力系统模型和燃料电池及能量管理策略模型并进行联合仿真.结果表明,采用文中提出的能量管理策略车辆经济性相对于开关式和能量跟随式两种控制策略分别提高62%和31%,续驶里程相对于该两种控制策略分别提高41%和18%.

燃料电池船舶混合动力系统能量管理研究综述

在“双碳”目标下,发展燃料电池船舶是实现航运业转型升级和低碳化的重要发展方向之一。面对当前燃料电池上船的诸多问题,混合动力系统成为燃料电池船舶应用的有效解决方案,其能量管理的研究也成为核心研究方向之一。系统梳理燃料电池船舶的发展概况,针对燃料电池船舶多类型能源能量管理中涉及的能量调度问题以及变换器功率分配问题进行综述;分析各类方法的优缺点及其在实船上应用的可能性;探讨燃料电池船舶推广可行性和发展方向,以期能为技术创新和工程应用提供参考。

基于优化功率跟随控制的E-REV能量管理策略研究

基于功率跟随控制的增程式电动汽车能量管理策略具有减缓电池寿命衰减与提高车辆NVH性能等优势,但存在阈值参数依赖性强、增程器启停频繁等问题,为此提出了一种基于优化功率跟随控制的E-REV能量管理策略。依据车速、SOC状态与驾驶员的加速踏板力度等信息特征,制定基于功率跟随控制的能量管理策略。在此基础上,针对固定规则参数的局限性,以车辆行驶总成本与SOC变化梯度为目标函数,结合灰狼优化算法对增程器启停功率阈值参数进行优化,减少发动机频繁启停现象。运用Matlab/Simulink搭建控制策略模型,并联合基于Simcenter/AMESIM搭建的整车物理模型进行仿真试验,结果表明:CHTC-LT循环工况下,优化功率跟随控制策略与功率跟随控制策略相比,SOC最大波动值降低了28%,增程器启停次数减少了28.5%,整车燃油经济性提升了6.89%。

基于充电行为电量规划的自适应能量管理策略

为提高插电式混合动力汽车(PHEV)的燃油经济性,以并联式PHEV为研究对象,考虑驾驶员充电行为,提出基于充电行为电量规划和等效燃油消耗最小策略(ECMS)的自适应能量管理策略。构建了包含不同类型工况的组合工况。根据驾驶员的充电行为特征(充电频率、充电上限、放电下限)进行充电行为分析,并进行4类工况电量消耗与燃油消耗ECMS策略下的离线仿真数据获取。根据驾驶员充电行为以及离线数据进行SOC轨迹的规划。结果表明:在电池SOC初始值分别为0.9、0.6时,提出的能量管理策略相较于基于电量消耗维持的等效燃油消耗策略,整车燃油经济性分别提升7.87%和13.1%。