内燃机车二级减振结构的研究

基于内燃机车柴油机和主发电机在运行过程中产生响应的叠加原理,提出了在柴油发电机组与底架之间加三向橡胶弹簧单元的二级减振结构,推导了振动方程并建立了Simulink仿真模型,利用有限元算法求解了其振动幅度,并对柴油发电机组的橡胶支承进行刚度优化.对二级减振结构模拟结果显示：该结构使得内燃机车的稳定振幅相对于传统一级减振结构减小了30％.     

CKD5型机车底架结构设计及有限元分析

CKD5型机车是大连机车车辆有限公司为刚果设计、生产的电传动内燃机车,其车体为外廊式底架承载单司机室结构,底架主要承担机车上部设备载荷及机车牵引和制动所产生的牵引力和制动力。介绍了底架钢结构及主要参数和底架有限元分析以及在设计中采取的相关措施。     

SDA1型交流传动内燃机车底架设计与分析

介绍了SDA1型交流传动内燃机车底架结构设计特点,并通过ANSYS软件对底架结构进行强度计算分析,确保其强度指标满足设计要求的同时还需对底架进行减重设计。     

HXD2型机车底架结构与强度研究

介绍了HXD2型机车车体底架的结构特点、材料选取和强度计算.计算结果表明,该车体底架的强度、刚度满足设计要求.     

CKD0型机车车体底架的设计

CKD0型机车是大连机车车辆有限公司为土耳其ISDEMIR钢铁厂设计、生产的矿用电传动内燃机车,其车体为外廊式底架承载单司机室结构,底架主要承担机车上部设备载荷及机车牵引和制动所产生的牵引力和制动力。介绍了该型机车底架的基本结构、主要参数、静强度计算以及在设计中采取的相关措施。     

机车车体强度计算中载重约束处理浅析

应用有限元方法及ANSYS软件建立了某型调车内燃机车车体结构的有限元分析模型,根据其机车的受力分析和承载特点,选底架作为分析对象,考虑载重的两种处理方式,确定了有限元模型的计算载荷和计算工况以及评定标准,比较了车体在整备状态下的车体静强度以及底架结构的变形情况。结果表明,底架结构的载重在两种处理方式下,其强度和变形相差很小,仅仅相差不到0 .5 %,且皆能满足相关标准的要求。     

DPU-30型机车底架裂纹和改进的分析研究

对大连机车车辆有限公司出口巴基斯坦的DPU-30型机车底架主梁出现的局部裂纹进行了大量的现场调查,同时对出现裂纹的原因和机理进行了理论分析,在此基础上对裂纹部位提出了改进方案以及在巴基斯坦铁路现场的修复措施。为了验证改进方案的有效性,对改进方案进行了有限元计算分析,并在巴基斯坦对修复后投入运用的机车底架的动应力进行了测试,所有这些研究均证明了改进方案的可靠性。     

油田直联驱动泥浆泵用集成机组

介绍了直联驱动泥浆泵用垂直反车调速型偶合器传动箱集成机组的研制情况。该机组的柴油机和垂直反车调速型偶合器传动箱安装在同一个公共底架上,柴油机通过一根较短的高弹联轴器与垂直反车传动箱相连。垂直反车传动箱输入轴中心与柴油机输出轴中心高保持一致,而其输出轴中心较柴油机输出轴中心高出一定距离,以达到与泥浆泵输入轴进行直联匹配的目的。垂直反车传动箱输出端通过万向轴与泥浆泵直接连接,机组可以对泥浆泵实现无级调速和离合功能。公共底架与泥浆泵的安装架之间有两套固定机构,以保持两底架稳固联接,使机组平稳、安全运行。     

燃气轮机下部传动箱试验台研制及应用

下部传动箱是燃气轮机的关键部件之一,起到传递扭矩、驱动燃/滑油泵的重要作用。为解决其机械 效率测试难、耐久性试验成本高的现状,研制出能模拟下部传动箱在燃气轮机上实际运行状态的试验台。该 试验台主要包括机械结构、润滑系统、负载系统和测控系统。总体设计方案采用了相似的安装方式,并用有 限元软件对底架进行模态分析,采用电涡流测功器作为加、卸负载设备,并使用LabView和PLC编制测控系 统软件。应用该试验台可进行下部传动箱机械效率分析,以及实时获取转速、功率、扭矩、振动等参数。该试 验台长周期无故障的应用,进一步证明研制的试验台可满足下部传动箱耐久性试验要求。     

CKD7B型电传动内燃机车车体设计

介绍了大连机车车辆有限公司出口缅甸的CKD7B型电传动内燃机车车体部分的主要技术参数以及车体设计中强度的计算过程.计算结果表明,底架强度满足要求,从而保证了机车的运用性能.     

Performance assessment of some ice TES systems

In this paper, a performance assessment of four main types of ice storage techniques for space cooling purposes, namely ice slurry systems, ice-on-coil systems (both internal and external melt), and encapsulated ice systems is conducted. A detailed analysis, coupled with a case study based on the literature data, follows. The ice making techniques are compared on the basis of energy and exergy performance criteria including charging, discharging and storage efficiencies, which make up the ice storage and retrieval process. Losses due to heat leakage and irreversibilities from entropy generation are included. A vapor-compression refrigeration cycle with R134a as the working fluid provides the cooling load, while the analysis is performed in both a full storage and partial storage process, with comparisons between these two. In the case of full storage, the energy efficiencies associated with the charging and discharging processes are well over 98% in all cases, while the exergy efficiencies ranged from 46% to 76% for the charging cycle and 18% to 24% for the discharging cycle. For the partial storage systems, all energy and exergy efficiencies were slightly less than that for full storage, due to the increasing effect wall heat leakage has on the decreased storage volume and load. The results show that energy analyses alone do not provide much useful insight into system behavior, since the vast majority of losses in all processes are a result of entropy generation which results from system irreversibilities.     

Effect of co-cultivation of Chlamydomonas reinhardtii with Azotobacter chroococcum on hydrogen production

Chlamydomonas reinhardtii cc124 and Azotobacter chroococcum bacteria were co-cultured with a series of volume ratios and under a variety of light densities to determine the optimal culture conditions and to investigate the mechanism by which co-cultivation improves H₂ yield. The results demonstrated that the optimal culture conditions for the highest H₂ production of the combined system were a 1:40 vol ratio of bacterial cultures to algal cultures under 200 μE m^?2 s^?1. Under these conditions, the maximal H₂ yield was 255 μmol mg^?1 Chl, which was approximately 15.9-fold of the control. The reasons for the improvement in H₂ yield included decreased O₂ content, enhanced algal growth, and increased H₂ase activity and starch content of the combined system.     

Exergetic evaluation of 5 biowastes-to-biofuels routes via gasification

This paper presents the exergy analysis results for the production of several biofuels, i.e., SNG (synthetic natural gas), methanol, Fischer–Tropsch fuels, hydrogen, as well as heat and electricity, from several biowastes generated in the Dutch province of Friesland, selected as one of the typical European regions. Biowastes have been classified in 5 virtual streams according to their ultimate and proximate analysis. All production chains have been modeled in Aspen Plus in order to analyze their technical performance. The common steps for all the production chains are: pre-treatment, gasification, gas cleaning, water–gas-shift reactions, catalytic reactors, final gas separation and upgrading. Optionally a gas turbine and steam turbines are used to produce heat and electricity from unconverted gas and heat removal, respectively. The results show that, in terms of mass conversion, methanol production seems to be the most efficient process for all the biowastes. SNG synthesis is preferred when exergetic efficiency is the objective parameter, but hydrogen process is more efficient when the performance is analyzed by means of the 1st Law of Thermodynamics. The main exergy losses account for the gasification section, except in the electricity and heat production chain, where the combined cycle is less efficient.     

液压系统常见的故障诊断及处理

任何工程机械式液压设备使用时出现故障是不可避免的。但是怎样确定故障的原因及找到好的解决方法，这是使用者最关心的问题。讲述了液压系统常见的故障及其排除方法。     

Economie d'énergie en trigénération

Trigeneration is defined as the production of three useful forms of energy—heat, cold and power—from a primary source of energy such as natural gas or oil. For instance, trigeneration systems typically produce electrical power via a reciprocating engine or gas turbine and recover a large percentage of the heat energy retained in the lubricating oil, exhaust gas and coolant water systems to maximize the utilization of the primary fuel. The heat produced can be totally or partially used to fuel absorption refrigerators. Therefore, trigeneration systems enjoy an inherently high efficiency and have the potential to significantly reduce the energy-related operation costs of facilities. In this paper, we describe a model of characterization of trigeneration systems trough the condition of primary energy saving and the quality index, compared to the separate production of heat, cold and power. The study highlights the importance of the choice of the separate production reference system on the level of primary energy saving and emissions reduction.     

Mineralogical characterization of the intraseam layers of Lofoi lignite deposits in Florina basin (western Makedonia,northwest Greece)

The mineralogical composition of intraseam layers from Lofoi lignite deposits (northwest Greece) is the subject of the present study. The samples were examined by means of X-ray diffraction (XRD), thermo-gravimetric (TG/DTG) and differential thermal analysis (DTA), and Fourier transform infrared (FT-IR) spectrometry. The clay minerals prevail in most samples, with illite-muscovite being the dominant phase, and kaolinite and chlorite being the other major clay components. No smectite was found. Quartz and feldspars, dominate in two cases. The studied materials are characterized as clays to clayey sands, showing significant similarities with the intraseam layers of the adjacent Achlada lignite deposits.     

Innovative methodologies in renewable energy: A review

This paper is concerned with innovative approaches to renewable energy sources computation methodologies, which provide more refined results than the classical alternatives. Such refinements provide additional improvements especially for replacement of fossil energy usages that emit greenhouse gas (GHG) into the atmosphere leading to climate change impact. Current knowledge gap among each renewable energy source calculation is rather missing fundamentals of plausible, rational, and logical explanations for the interpretation of results. In the literature, there are rather complicated and mechanically applicable methodologies, which require input and output measurement data match with missing physical explanations. The view taken in this review paper is to concentrate on quite plausible, logical, rational, and effectively applicable innovative energy calculation methodologies with simplistic fundamentals. For this purpose, a set of renewable energy methodological approaches is revisited with their innovative structures concerning solar, wind, hydro, current, and geothermal energy resources. With the increase in the renewable energy utilizations to combat the undesirable impacts of global warming and climate change, there is a need for better models that will include physical environmental conditions and data properties in the probabilistic, statistical, stochastic, logical, and rational senses leading to refined and more reliable estimations with application examples in the text. Finally, new research directions are also recommended for more refined innovative energy system calculations.     

Constrained Optimization of Heat Transfer from an Extended Surface

Two different zero‐order optimization techniques are used to maximize the rates of heat transfer from a fin assembly of a specified cost and in the shape of several annular fins that are mounted on a central stem. The problem is formulated to account for two‐dimensional steady‐state heat transfer that is limited by several inequality constraints. The dimensionless governing equations are used to identify the relevant decision variables. The number of fins making up the assembly is treated as an input parameter. A digital computer is used to determine the required temperature distributions and to implement the optimization search algorithms. Three different fin materials are assessed—aluminum, copper and carbon steel. Design optimizations of the extended surface assembly were made over a range of operating conditions, encompassing several different convection heat transfer coefficients that are representative of free and forced convection in air, and several different overall temperature differences between the substrate surface and air. A few recommendations based on trends in the predicted results are given. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res, 43(6): 504–521, 2014; Published online 3 October 2013 in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21093     

CY6D78Ti型柴油机的开发研制

本文介绍了CY6D78Ti型柴油机的开发研制过程及现状,CY6D78Ti型柴油机能满足国内中、重型卡车和豪华客车市场对柴油机动力性、经济性、可靠性的需求。由于该机型的高档配置,保证了其排放达到欧Ⅱ标准,同时为进一步提高性能、降低排放,采用电控及高压共轨等技术手段搭建了平台。     

我国车用柴油机的技术现状及发展趋势

本文根据国内外信息和资料，分析了我国目前车用柴油机制造技术方面与国际水平所存在的差距，预测今后若千年内车用柴油机要向节能降耗、应用增压技术、提高可靠性、降低排放、采用电控技术方面发展，以尽快接近和赶上国际先进水平．