汽油机机油消耗量的试验与分析

润滑油对发动机有非常重要的作用,发动机中影响机油消耗的因素也很多。本文针对不同的缸盖护罩、活塞、二道气环和油环背压,在电控汽油机上进行了机油消耗量的试验和分析。试验结果表明:总机油消耗主要包括活塞部分机油消耗和强制通风口机油消耗两部分,其中活塞部分机油消耗占总机油消耗的90%以上;改进型缸盖护罩能有效冷凝机油蒸汽,降低机油的蒸发消耗;对二道气环的改进能减少活塞环的磨损,并提高刮油效果;确保活塞与气缸贴合的更好,能有效阻止窜气的发生;油环背压的增加能够改善刮油效果,但由于同时增加了活塞环的磨损,在实验后期机油消耗量反而增加。     

TCD2015V08柴油机废气大故障分析

针对TCD2015V08柴油机在试验过程中出现的废气大、机油压力降低等故障,通过对故障件,如箱体、气缸盖、缸套、活塞主轴瓦连杆瓦、水泵等技术状态的检查和分析,确认系气缸盖回油孔与水腔壁裂,致冷却液与机油混合,造成了废气大、机油压力降低的故障;相应地提出了改进设计方案。     

活塞环轴向动态对机油消耗量的影响

汽油机活塞油环矮型环窜气机油消耗量本文研究的目的是解决因燃油经济性、功率和发动机转速的提高而带来的机油消耗量增大的问题。解决的办法是减小第１和第２道气环的开口间隙，测试了活塞环性能及活塞环张力，而且还研讨了活塞第３环岸泄油孔对机油消耗量的影响。研究的结果是减少活塞第１环岸处的窜气回流、合理控制较低的活塞环张力及活塞第３环岸开泄油孔，可降低机油消耗量     

柴油机机油耗的优化改进及试验研究

以某柴油机为研究对象,针对低功率段柴油机排气歧管出现漏机油现象,对活塞油环槽上下侧面直线度、油环槽油带以及油环槽槽下侧面中的回油孔、泄油槽等设计参数进行优化和试验验证。结果表明:活塞油环槽下侧面增加回油孔设计使机油耗量由原型产品的19. 4 g/h降低到7. 5 g/h,柴油机漏机油试验通过率达98. 4%,从而有利于解决柴油机漏机油问题,对柴油机有效地降低机油消耗有指导意义。     

汽油机机油消耗量的试验与分析

润滑油对发动机有非常重要的作用，发动机中影响机油消耗的因素也很多。本文针对不同的缸盖护罩、活塞、二道气环和油环背压，在电控汽油机上进行了机油消耗量的试验和分析。试验结果表明：总机油消耗主要包括活塞部分机油消耗和强制通风口机油消耗两部分，其中活塞部分机油消耗占总机油消耗的90％以上；改进型缸盖护罩能有效冷凝机油蒸汽，降低机油的蒸发消耗；对二道气环的改进能减少活塞环的磨损，并提高刮油效果；确保活塞与气缸贴合的更好，能有效阻止窜气的发生；油环背压的增加能够改善刮油效果，但由于同时增加了活塞环的磨损，在实验后期机油消耗量反而增加。     

车用发动机曲轴箱通风系统构成及常见故障分析

随着国家排放法规要求越来越严格,曲轴箱通风系统对整车排放的影响越来越大。本文介绍了车用发动机曲轴箱通风系统的构成及功能,构成包括通风腔、油气分离系统、曲轴箱压力控制系统、回油腔及呼吸管五部分;同时介绍了曲轴箱通风系统常见的故障模式并分析了失效原因,通常的故障模式包括:曲轴箱压力异常,烧机油,呼吸管结冰。     

柴油机曲轴箱通风系统设计与试验研究

对直列4缸柴油机的曲轴箱通风系统进行设计和CAE分析,对窜气流量、曲轴箱压力、油气分离模块压降及窜气中机油含量进行试验研究。分析了曲轴箱通风系统设计要点,以及用CAE分析软件对设计进行分析,对设计进行试验验证,验证结果表明,满足设计要求。     

探究增压直喷机型机油稀释的影响因素及解决方法

机油稀释现象是发动机常见的试验表象之一,尤其是增压缸内直喷汽油发动机,机油稀释较明显。机油发生稀释后会破坏机油使用性能,降低运动粘度,严重时还导致机油压力下降,零部件功能丧失,发动机可靠性下降。主要分析一款1.8L GDI缸内增压直喷发动机产生机油稀释的影响因素进而对机油牌号、机油温度、水温、SOI角度、曲轴箱通风系统、活塞漏气量、喷油器布置方式进行Benchmark分析及优化验证,为改善增压直喷发动机机油稀释现象提供解决方法,机油稀释包括燃油喷射稀释和机油挥发稀释,重点探究的方向是燃油喷射稀释。     

TSI汽油机机油消耗高的原因与对策

主要针对可能导致TSI汽油机机油消耗高的原因,从TSI汽油机的工作原理和发动机的曲轴箱通风系统、涡轮增压器等部件的结构加以分析,并提出一些改进措施及可行的解决办法。     

基于缸套失圆的活塞环结构参数对密封与摩擦性能的影响研究北大核心CSCD

以某非道路高压共轨柴油机为研究对象,采用仿真和测试相结合的方法,建立了整机耦合装配模型与活塞环组动力学模型,研究了干式缸套的失圆变形。在考虑缸套失圆变形的基础上,研究了活塞环结构参数对窜气量、机油消耗量和摩擦损失的影响,并通过正交设计方法进行了活塞环径向弹力、开口间隙和侧向间隙对窜气量、机油消耗和摩擦损失的影响研究。研究结果表明,活塞环结构参数中,二环径向弹力、二环开口间隙和顶环侧向间隙对窜气量的影响最大,油环径向弹力、二环开口间隙和顶环侧向间隙对机油消耗量的影响最大,油环径向弹力、油环开口间隙和油环侧向间隙对摩擦损失的影响最大。     

我国经济和社会发展中必须重视石油峰值问题

石油峰值(Peak Oil)是指某一区域(全球、地区、国家、油区等)石油产量的最大值及其来临的时间。世界石油产量到达峰值并不意味着全世界已将石油消耗怠尽,也不意味着人类不可能在地球上再发现新的油田,只是新发现的油田的石油产量越来越无法弥补已开发油田产量的下降,世界石油供应量不可能再增加,不能满足人类日益增长的需求。许多研究表明世界石油产量正在进入峰值平台期,随时都可能出现资源长期短缺的石油危机。我国的石油消费一直以较快的速度增长,石油也许很快成为我国经济发展的瓶颈。本文提出了石油峰值——我国经济和社会发展中必须重视的一个重大问题,希望大家尤其是主管部门和高层决策者充分认识石油峰值的内涵和挑战,高度重视我国面临的潜在的石油危机,认真落实科学发展观、未雨绸缪,提早采取应对策略以实现我国经济社会的可持续发展。     

美国战略石油储备补仓和释放策略分析

美国是最早建立战略石油储备的国家之一,自20世纪70年代开始已逐步形成了一套比较完善的战略石油储备决策管理体系。历史数据表明,美国战略石油储备的几次释放和补仓时机都把握得很好,充分发挥了战略石油储备保障国家石油供应安全、平抑国际原油价格的作用。本文系统地介绍和分析了美国战略石油储备几次主要的释放和补仓策略,以期为探讨我国战略石油储备的补仓和释放时机与策略,提供决策信息参考。     

开发难动用储量保障国家石油安全

保障我国石油安全有多种措施：建立石油储备、发展替代能源、降低能耗、从国外获取稳定的石油供应、加大国内石油资源的勘探开发力度等。其中，加强国内石油资源的勘探开发是最重要的途径。本文针对我国陆上近４０亿ｔ已探明难动用石油地质储量的现实，从国家石油政策、技术进步、开发方式和机制、评价方法和参数等方面论述了促进难动用储量开发，保障国家石油安全的途径。     

我国急需发展石油期货市场

本文从我国石油需求逐年上升、对进口依赖性不断提高以及国际石油市场起伏不定的现实出发,分析论述了我国发展石油期货市场的必要性和可行性,并提出了发展石油期货市场方面的建议。     

Mitigation of maximum world oil production: Shortage scenarios

A framework is developed for planning the mitigation of the oil shortages that will be caused by world oil production reaching a maximum and going into decline. To estimate potential economic impacts, a reasonable relationship between percent decline in world oil supply and percent decline in world GDP was determined to be roughly 1:1. As a limiting case for decline rates, giant fields were examined. Actual oil production from Europe and North America indicated significant periods of relatively flat oil production (plateaus). However, before entering its plateau period, North American oil production went through a sharp peak and steep decline. Examination of a number of future world oil production forecasts showed multi-year rollover/roll-down periods, which represent pseudoplateaus. Consideration of resource nationalism posits an Oil Exporter Withholding Scenario, which could potentially overwhelm all other considerations. Three scenarios for mitigation planning resulted from this analysis: (1) A Best Case, where maximum world oil production is followed by a multi-year plateau before the onset of a monatomic decline rate of 2–5% per year; (2) A Middling Case, where world oil production reaches a maximum, after which it drops into a long-term, 2–5% monotonic annual decline; and finally (3) A Worst Case, where the sharp peak of the Middling Case is degraded by oil exporter withholding, leading to world oil shortages growing potentially more rapidly than 2–5% per year, creating the most dire world economic impacts.     

Feasibility of edible oil vs. non-edible oil vs. waste edible oil as biodiesel feedstock

Biodiesel has high potential as a new and renewable energy source in the future, as a substitution fuel for petroleum-derived diesel and can be used in existing diesel engine without modification. Currently, more than 95% of the world biodiesel is produced from edible oil which is easily available on large scale from the agricultural industry. However, continuous and large-scale production of biodiesel from edible oil without proper planning may cause negative impact to the world, such as depletion of food supply leading to economic imbalance. A possible solution to overcome this problem is to use non-edible oil or waste edible oil (WEO). In this context, the next question that comes in mind would be if the use of non-edible oil overcomes the short-comings of using edible oil. Apart from that, if WEO were to be used, is it sufficient to meet the demand of biodiesel. All these issues will be addressed in this paper by discussing the advantages and disadvantages of using edible oil vs. non-edible vs. WEO as feedstock for biodiesel production. The discussion will cover various aspects ranging from oil composition, oil yield, economics, cultivation requirements, land availability and also the resources availability. Finally, a proposed solution will be presented.     

Performance and emission characteristics of a DI compression ignition engine operated on Honge, Jatropha and sesame oil methyl esters

The high viscosity of vegetable oils leads to problem in pumping and spray characteristics. The inefficient mixing of vegetable oils with air contributes to incomplete combustion. The best way to use vegetable oils as fuel in compression ignition (CI) engines is to convert it into biodiesel. Biodiesel is a methyl or ethyl ester of fatty acids made from vegetable oils (both edible and non-edible) and animal fat. The main resources for biodiesel production can be non-edible oils obtained from plant species such as Pongamia pinnata (Honge oil), Jatropha curcas (Ratanjyot), Hevea brasiliensis (Rubber) and Calophyllum inophyllum (Nagchampa). Biodiesel can be used in its pure form or can be blended with diesel to form different blends. It can be used in CI engines with very little or no engine modifications. This is because it has properties similar to mineral diesel. This paper presents the results of investigations carried out on a single-cylinder, four-stroke, direct-injection, CI engine operated with methyl esters of Honge oil, Jatropha oil and sesame oil. Comparative measures of brake thermal efficiency, smoke opacity, HC, CO, NO_X, ignition delay, combustion duration and heat release rates have been presented and discussed. Engine performance in terms of higher brake thermal efficiency and lower emissions (HC, CO, NO_X) with sesame oil methyl ester operation was observed compared to methyl esters of Honge and Jatropha oil operation.     

近期石油市场供需形势分析

5月份受SARS疫情影响,国内石油消费需求下降;另一方面,5月以来石油资源增势有所回落,原油及成品油的增幅较之1季度均有不同程度减缓,又加之受国际行情下挫等诸多因素的共同作用,使得国内持续走高的油价大幅下跌。在多方面力量推动下,进入6月以来上述情况有所缓解。通过对近期国内外经济走势的综合分析,认为随着SARS疫情得到有效控制,国内各油品市场油品销售将会有不同程度的提高,市场后期形势趋于回升。     

Factors Affecting the Oil Agglomeration of Sivas-Divriği Uluçayır Lignite

Abstract

In the coal industry, the coal particles need to be decreased to a very fine size because of the need of removing inorganic materials from coal. Oil agglomeration is a kind of coal cleaning technique that is used for separation of organic and inorganic parts of fine sized coal. In this study, the oil agglomeration of Sivas-Divri?i (S-D) Uluçay?r lignite was carried out by using kerosene, diesel oil, fuel oil, poppy oil, and sunflower oil. The amount of bridging oil was varied from 5% to 25% of the amount of lignite. The effect of oil amount, oil type, solid content, agitation rate and time, pH on agglomeration performance was investigated. Maximum recovery value of 98.18% was observed by using poppy oil. In order to investigate the effect of pH on agglomeration NaOH and HCl is added to the slurry in various amounts. It is decided that the best agglomeration condition is obtained at low pH values. The effect of nonionic surface active agent (Igepal-CA 630) on agglomeration is investigated by adding to the slurry and it is observed that the grade is increased with the amount of surface active agent.     

对燃油锅炉渣油供油系统的工艺改进

针对渣油特性及其应用过程中易发生的问题，介绍了供油系统的几项有效改进措施。