首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
舰船燃气轮机双机并车控制仿真技术研究   总被引:5,自引:1,他引:4  
介绍了功率反馈控制技术的原理和特点,并利用功率反馈控制技术对舰船燃气轮机双机并车控制技术进行了分析.利用C++语言建立了全燃动力装置的仿真模型,并对功率反馈法进行了计算机仿真试验.结果表明,功率反馈控制技术能较好地实现舰船燃气轮机双机并车运行的控制.  相似文献   

2.
针对实车检测坦克柴油机比油耗的原理和方法作了探讨,对12150L柴油机进行了实车比油耗测试,认为用无负荷方法实车测定柴油机有效功率,同时用涡轮流量计测量燃油消耗量是实车测量发动机比油耗可行的方法。  相似文献   

3.
柴油机有害排放物控制的新发展   总被引:1,自引:1,他引:0  
简要介绍柴油机的有害排放物质,重点回顾了近几年柴油机排放控制技术的进展。提出现代柴油机有害排放物的控制是一个综合的、系统的工程,以改进柴油机设计技术为核心,与燃料改质和排气后处理系统相结合将是未来降低排放研究的主要思路。并对柴油机排放控制技术今后的研究重点进行了预测。  相似文献   

4.
船用柴油机是舰船动力系统的主要设备,确定舰船服役年限必须掌握柴油机的使用寿命.柴油机的使用寿命取决于自然损耗、技术性能以及使用的经济性,用自然寿命、技术寿命和经济寿命的最小值表示.提出一种柴油机使用寿命确定方法:将柴油机重要运动部件的磨损率和磨损量以及容许磨损量当作随机变量,建立计算这些部件寿命的数学模型,确定柴油机的...  相似文献   

5.
某型水陆坦克功率转换装置存在着操作不便的缺陷,影响了其机动性.为解决上述问题,在对相关技术进行深入研究的基础上,提出了采用电磁换向进行液压控制的双功率转换装置代替原有功率转换装置,并进行了台架和实车试验.试验表明,采用液压控制双功率转换装置,不仅提高了水陆坦克车辆操纵的灵活性和机动性,还彻底解决了以往驾驶员必须停车才能进行功率转换的被动局面.  相似文献   

6.
针对以燃气轮机为原动力的舰船综合电力系统动态性能易受舰船大功率用电负载突变、高能武器投切、电网故障等的影响问题,首先提出采用短时高功率的飞轮储能系统并入船舶电网以平缓系统功率波动;然后,结合综合优化弱磁控制建立了飞轮充放电控制模型,并对并网侧变流器控制进行了优化改进,实现飞轮充电模式下直流电压快速稳定、增强抗扰性能及放电并网模式下输出功率可控;最后,利用仿真软件分析了飞轮储能系统并网下负载突变导致的燃气动力轮机涡轮转速、电网频率、电压幅值及功率的变化。结果表明:飞轮储能系统的投入对舰船电网电压凹陷具有抑制作用,能够减缓负载突变导致燃气轮机动力涡轮转速变化及增加电网频率稳定性,有效提高了舰船综合电网整体性能。  相似文献   

7.
针对舰船柴油机冷却系统水垢、锈垢严重,维修保养困难的问题,提出舰船柴油机冷却系统不解体清洗技术。通过对舰船柴油机冷却系统材质和垢样的分析,提出由清洗主剂、缓蚀剂和清洗助剂为基础的6种清洗剂配方。对比6种清洗剂配方的缓蚀与清洗效果,确定了最优的清洗剂配方。经柴油机台架试验发现,不解体清洗可有效清除汽缸缸套、缸体等部位的积垢,清除率可达81%,显著改善了热交换效果。  相似文献   

8.
详细地阐述了舰船动力装置采用主动振动控制技术的必要性和可行性,并对该技术的最新发展进行了综述。  相似文献   

9.
柴油机电控冷却系统性能仿真   总被引:3,自引:0,他引:3  
为了精确控制柴油机出水温度,降低冷却系统功率消耗,以某型柴油机冷却系统为研究对象,建立了该型柴油机冷却系统仿真模型,并将机械水泵改为电控水泵进行了变工况仿真计算。结果表明:电控水泵耗功小于机械水泵,平均效率提高1.31%,能够精确控制柴油机出水温度。通过该型柴油机热平衡实验,在外特性上验证了该冷却系统仿真模型是可信的。  相似文献   

10.
前言柴油机-螺旋桨系统是目前大部分舰船的推进动力源。研究舰船-柴油机-螺旋桨系统中关于柴油机在稳定工况中经济工作区域的确定、在非稳定工况中不同的操纵方法导致的柴油机整机负荷的变化规律及舰船机动性的变化规律这二个问题,就成为非常迫切了。研究方法有许多种,建立在相似理论基础上的模拟法是其中的一种。本文概要地介绍了×型护卫舰模型的一般概况;遥测、遥调(遥控)的主要设备和性能;柴油机特性模拟方法及初步试验结果。  相似文献   

11.
Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).  相似文献   

12.
In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.  相似文献   

13.
This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.  相似文献   

14.
The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.  相似文献   

15.
This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.  相似文献   

16.
装备的RMS是装备的重要设计参数,是影响战备完好和保障能力的关键因素.引入GTST-DMLD作为主要建模工具,建立起装备系统的RMS描述模型,以ESD为补充和扩展,对维修过程进行建模.并以GTST-DMLD-ESD模型作为装备RMS仿真的核心,对装备RMS仿真模型的总体框架进行了研究,并对各模块进行了较为详细的探讨.  相似文献   

17.
18.
ABSTRACT

What was the scope of the Bosnian jihadi participation in the war in Syria? Did the Bosnian volunteers tend to join one particular faction? Why did the Bosnian youngsters decide to join the holy war in the Levant? Was this an organized and hierarchical process or was this a grassroots movement? Last, were all the Salafis in Bosnia supportive of this dynamic or did this process cause internal frictions? These are some of the questions that this research will try to answer.  相似文献   

19.

The Soviet Union was able to develop a large military-industrial complex and become the world's second superpower despite deficiencies in its centrally planned economy because defence was given high priority status and special planning, rationing and administrative mechanisms were used to attain national security objectives. However, in the period 1976-85 the effectiveness of priority protection diminished and defence institutions experienced more of the problems typical of the shortage economic system. The heavy defence burden also created growing difficulties for the civilian economy. The attempts by the Gorbachev government to reform the defence sector and improve defence-economic relationships during perestroika (1985-91) uniformly failed. For most of the transition period, the Russian military-industrial complex has been adversely affected by its low priority status, cuts in defence spending, instability of the hybrid politico-economic system, and negative growth of the economy. The armed forces and defence industry have been reduced in size and their outputs of military services and equipment have fallen to low levels. Nevertheless, the Russian armed forces still have over one million troops, significant stocks of sophisticated conventional weapons, and a large nuclear arsenal. The government of President Putin has raised the priority of the defence sector, increased real defence spending, and adopted ambitious plans to revive Russian military power. It is likely, though, that tight resource constraints will hamper efforts to reform the armed forces and to upgrade weapons. By 2010 Russia will be an important, but not dominant, military power in Eurasia.  相似文献   

20.
The collapse of the Soviet Union precipitated the massive expansion of drug use and trade in Russia. The country now has one of the largest populations of injecting drug users in the world and has become the largest single-country market for Afghan heroin. In 2003 the Federal Service for the Control of the Drugs Trade was created to coordinate a comprehensive counternarcotics strategy appropriate to the scale of this threat. The service continues to face a number of challenges in its early stages of development. However, it has made considerable advances in improving responses to large-scale organised crime and in building international cooperation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号