Integrated gas analyzer for complete monitoring of turbine engine test cells

Fourier transform infrared (FT-IR) spectroscopy is proving to be reliable and economical for the quantification of many gas-phase species during testing and development of gas turbine engines in ground-based facilities such as sea-level test cells and altitude test cells. FT-IR measurement applications include engine-generated exhaust gases, facility air provided as input to engines, and ambient air in and around test cells. Potentially, the traditionally used assembly of many gas-specific single gas analyzers will be eliminated. However, the quest for a single instrument capable of complete gas-phase monitoring at turbine engine test cells has previously suffered since the FT-IR method cannot measure infrared-inactive oxygen molecules, a key operational gas to both air-breathing propulsion systems and test cell personnel. To further the quest, the FT-IR sensor used for the measurements presented in this article was modified by integration of a miniature, solid-state electrochemical oxygen sensor. Embedded in the FT-IR unit at a location near the long-effective-optical-path-length gas sampling cell, the amperometric oxygen sensor provides simultaneous, complementary information to the wealth of spectroscopic data provided by the FT-IR method.     

内燃机燃烧测试分析系统的设计与开发

开发一套基于PC机的内燃机燃烧测试分析系统,并对气缸压力的采集,数据的匀化、光顺处理,动态上止点位置的确定等做介绍。利用测量的气缸压力曲线和能量守恒原理,在LabVIEW软件平台上编写出内燃机燃烧放热率计算程序,研究主要经验参数对放热率及缸内平均温度的影响。结果表明:采用Woschni传热公式计算的放热率曲线值高于采用Eichelberg传热公式和Sitkei传热公式计算的放热率曲线值。扫气系数φs的变化对气缸内平均温度有显著影响,φs=0.99时的缸内平均温度明显高于φs=0.95时的缸内平均温度,两者最高温度相差81.4 K。     

A new decomposition algorithm for a liquefied natural gas inventory routing problem

We consider an inventory routing problem (IRP) in the liquefied natural gas (LNG) supply chain, called the LNG-IRP. Here, an actor is responsible for the LNG production and inventory management at the liquefaction plants, the routing and scheduling of a heterogeneous fleet of LNG ships, as well as the inventories and sales at the regasification terminals. Furthermore, all ports have a limited number of berths available for loading and unloading. The LNG-IRP is more complicated than many other maritime inventory routing problems because a constant rate of the cargo evaporates in the tanks each day and is used as fuel during transportation. In addition, a variable number of tanks are unloaded at the regasification terminals. We introduce a new path flow formulation for this problem arising from a novel decomposition scheme based on parts of a ship schedule, called duties. A ship schedule for the entire planning horizon can be divided into duties consisting of a visit to a liquefaction plant, then one or two visits to a regasification terminal before ending in a liquefaction plant. The solution method suggested is based on a priori generation of duties, and the formulation is strengthened by valid inequalities. The same problem was previously solved by a branch-price-and-cut algorithm for a schedule-based formulation. Computational results show that the new formulation provides tighter bounds than the previous schedule-based formulation. Furthermore, on a set of 27 benchmark instances, the proposed algorithm clearly outperforms the previous branch-price-and-cut algorithm both with regard to computational time and the number of problems solved within a 10-h time limit.     

燃气机热泵机组的研制与实验研究

设计开发了一台面向商用的天然气发动机驱动风冷热泵冷热水机组(简称"燃气机热泵").对燃气机热泵的设计方法和安装问题进行了介绍.重点对系统设计中的机组型式的选择、热泵(制冷)系统的设计要点、发动机和压缩机的匹配,以及余热回收和散热系统的设计这四个方面进行了论述.对机组在不同环境温度、不同出水温度和不同转速下冷热量和一次能耗进行了测试.     

A new high temperature resistant glass-ceramic coating for gas turbine engine components

A new high temperature and abrasion resistant glass-ceramic coating system (based on MgO-Al₂O₃-TiO₂ and ZnO-Al₂O₃-SiO₂ based glass systems) for gas turbine engine components has been developed. Thermal shock resistance, adherence at 90°-bend test and static oxidation resistance at the required working temperature (1000°C) for continuous service and abrasion resistance are evaluated using suitable standard methods. The coating materials and the resultant coatings are characterized using differential thermal analysis, differential thermogravimetric analysis, X-ray diffraction analysis, optical microscopy and scanning electron microscopy. The properties evaluated clearly showed the suitability of these coatings for protection of different hot zone components in different types of engines. XRD analysis of the coating materials and the resultant coatings showed presence of a number of microcrystalline phases. SEM micrographs indicate strong chemical bonding at the metal-ceramic interface. Optical micrographs showed smooth glossy impervious defect free surface finish.     

工业炸药有毒气体测试容器的研制

针对测量工业炸药有毒气体含量的爆炸弹筒法无法应用在大药量和常压情况下的难题,通过爆炸相似率和动力系数法进行理论计算及工程设计,研制出了容积15 m³下端为圆柱体,顶端为半球形结构的大型密闭爆炸容器。研制的爆炸容器可以研究工业炸药在常压状态下的爆炸气体产物,并对其有毒气体含量进行分析,解决了爆炸弹筒法由于装药量小且必须在真空状态下引爆炸药的困境。同时通过气密性及抗爆性试验对爆炸测试容器进行了进一步的安全测试,均无异常。设计结果表明该爆炸容器用于工业炸药有毒气体测试安全可靠、功能满足试验要求。研制方法可为同类型爆炸容器的设计提供参考。     

160万m~3/d天然气透平膨胀机的研制

介绍了160万m3/d天然气透平膨胀机的设计参数和运行参数,重点分析了透平膨胀机设计中遇到的问题及解决措施,调整设计参数和运行参数后,透平膨胀机运行性能良好,最后总结了天然气透平膨胀机设计中的经验教训。     

A pyrolysis cell as simulator for an automobile catalytic converter

We studied the behaviour of some aromatic hydrocarbon molecules (benzene, toluene and xylene) and their reaction with water as a function of temperature and water content in a pyrolysis cell. We also investigated these substances as parts of two types of unleaded gasolines of two brands available in the Portuguese market.     

Simulation and validation of a hybrid-power gas engine heat pump

Hybrid-power gas engine heat pump (HPGHP) combines hybrid power technology with gas engine heat pump, which can keep the gas engine working in the economical zone. In this paper, a steady-state model of the HPGHP in heating condition has been established, the optimal torque curve control strategy is proposed to distribute power between the gas engine and battery pack. The main operating parameters of the HPGHP system are simulated on Matlab/Simulink and validated by experimental data, such as operating temperature, coefficient of performance (COP), fuel-consumed rate, etc. Heating capacity and COP of the heating pump system are validated under different ambient temperatures and water flow rates. The simulation and experiment results shows acceptable agreement, the maximum difference is respectively 8.9%, 5.9%, 9.5% and 8.2% for engine torque, motor torque, reclaimed heat and fuel-consumed rate. Based on the simulation results, HPGHP has the lowest fuel-consumed rate of 283 g (kWh)⁻¹ at engine speed of 3000 rpm; the PER of HPGHP system is about 15.9% and 11.4% higher than the GHP under the same load in Mode C and D.     

新型汽车起动机综合测试设备的研制

 介绍了一种新型汽车起动机综合测试设备的系统设计及关键技术，包括模块化模拟蓄电池开关电源的设计、多功能机械台架的开发、气一液比例控制模拟负载的智能PID控制等．该设备已在起动机生产线上稳定良好地运行．     

Procedure and test unit for studying the operating capacity of gas turbine engine blades under the combined action of mechanical and thermal loads,and atmosphere in a gas-dynamic test bed

A procedure and a gas-dynamic test bed are described for testing gas turbine engine blades with programmed mechanical and thermal loading. The test bed provides fatigue and heat resistance tests for GTE blades under conditions of the corrosive action of a high-temperature gas stream including variable thermodynamic parameters as well as other corrosive components, for example sea water salts injected into the stream in order to simulate GTE marine operating conditions.Deceased.Translated from Problemy Prochnosti, No. 6, pp. 71–77, June, 1993.     

Metrological certification of a piston flowmeter for natural gas flows

The results of metrological certification of piston flowmeter RPDU-41pg for natural gas flows are examined.Translated from Izmeritel'naya Tekhnika, No. 11, pp. 28–30, November, 1995.     

A four-way catalytic system for control of emissions from diesel engine

The pollution caused by diesel-fuelled vehicles has become a subject of global concern. Presently, various separate technologies such as diesel oxidation catalyst, diesel particulate filter, selective catalytic reduction and ammonia selective catalytic reduction are used to control these pollutants. The four-way catalytic (FWC) system integrates all the separate control systems into a single compact unit. FWC technique using a combination of oxidation–reduction catalysts under various strategies has been investigated to simultaneously remove CO, HC, PM and NOx emitted from diesel engines. An oxidation catalyst (La_0.6K_0.4CoO₃) was prepared by two different methods (sol–gel and co-precipitation). The reduction catalysts: Ag/Al₂O₃ and Cu-ZSM5 were synthesized by impregnation and ion-exchange method, respectively. The FWC was characterized by N₂-sorption, X-ray diffraction, Fourier transform spectroscopy and scanning electron microscopy. The catalytic activities of FWC containing double-layer of catalysts were evaluated in a fixed-bed-tubular-reactor. The highest catalytic activity resulted by the two-layered system of La_0.6K_0.4CoO₃ (sol–gel)?+?Cu-ZSM5 showing 100% NO conversion to N₂ at 415°C, maximum-temperature of soot-combustion at 410°C, complete C₃H₈ conversion at 450°C and 100% CO conversion at 388°C. Maximum NO conversion was maintained up to 427°C; conversion started decreasing with further increase in temperature and 75.4% conversion remained up to 450°C. The performance of double-layered-catalytic-system was as follows: La_0.6K_0.4CoO₃(sol–gel)?+?Cu-ZSM5?>?La_0.6K_0.4CoO₃(sol–gel)?+?Ag/Al₂O₃?>?La_0.6K_0.4CoO₃(co-ppt)?+?Ag/Al₂O₃?>?La_0.6K_0.4CoO₃(co-ppt)?+?Cu-ZSM5.     

地铁车辆辅助变流柜噪声试验研究

为了识别地铁车辆辅助变流器在不同运行工况下的气动噪声和电磁噪声特征以及贡献,通过试验方法对变流柜整机以及其内部2个主要的噪声源部件单体(风机和变压器)进行噪声测试.通过单体测试,分别得到风机和变压器在不同工况下的峰值频率以及对应幅值,为变流柜下一步降噪提供理论依据.     

基于Modelica的生物质燃气内燃机性能模拟研究

针对由沼气成分及其理化特性导致的内燃机燃用沼气时会发生燃烧速度慢、后燃严重、排气温度高等问题,将生物质燃气内燃机作为研究对象,基于可重用性及面向对象的Modelica语言建立内燃机模型库,将生物质燃气为燃料对四缸四冲程火花点火内燃机性能进行分析.通过仿真研究不同比例天然气(体积分数分别为33%,67%及100%)和LP...     

Failure analysis of a natural gas pipeline

In the present work, the failure investigation of a 30 in. diameter gas transmission pipeline (API 5L X-60 grade steel) has been described. The failure was due to a longitudinal crack developing in the centerline of longitudinal weld joint. Mechanisms and morphology of crack initiation and propagation were studied through different tests including: thickness measurement, chemical composition analysis, metallographic inspection, mechanical property testing, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The experiments resulted to the conclusion that some factors associated with Sulphide Stress Cracking (SSC) and metallurgical defects cause the failure of weld joint pipe. Detailed examination revealed that these factors are inappropriate welding parameters, pitting corrosion on longitudinal weld, and hydrogen permeation to the weld metal.     

自动测试系统中新技术的发展及应用

为了让国内自动测试领域的从业人员对测试新技术的发展现状和应用有一个清楚的了解,以及为我国自动测试系统的升级改造和研制提供参考.在参考和查阅大量资料基础上对近年来测试领域中出现的新技术,包括合成仪器技术、LXI总线技术、柔性测试技术和IVI信号接口技术的基本概念,发展和应用进行了详细地概述,讨论并指出了测试系统发展的新方向.     

Failure analysis of a natural gas pipeline

A L390 natural gas pipeline exploded in 2011 in China. Macrofracture examination, thickness measurement, chemical composition analysis, metallographic inspection, mechanical property testing, fracture scan electronic microscopy examination and environment analysis were conducted to the burst pipeline. The results showed that Stress Corrosion Cracking (SCC) generated in the mechanical damaged zone of the pipeline was the reason of the failure. This kind of cracking was induced by Cl⁻ and HCO₃⁻ in near neutral corrosive medium of pH value. The stress concentration was induced by the groove damage under inner pressure.