汽车磨期的使用

配合零件摩合阶段的磨损主要与零件表面的加工质量吸磨合规范有关。在这个阶段如何使用不当或不正确地执行磨合规范，将影响配合零件的工作期限。汽车磨合期就是为了使汽车更好地向正常使用阶段进行过滤，以提高汽车的使用寿命。     

汽车磨合期的使用

配合零件磨合阶段的磨损主要与零件表面的加工质量及磨合规范有关。在这个阶段如果使用不当或不正确地执行磨合规范 ,将影响配合零件的工作期限。汽车磨合期就是为了使汽车更好地向正常使用阶段进行过渡 ,以提高汽车的使用寿命     

汽车磨合期的使用

配合零件磨合阶段的磨损主要与零件表面的加工质量及磨合规范有关.在这个阶段如果使用不当或不正确地执行磨合规范,将影响配合零件的工作期限.汽车磨合期就是为了使汽车更好地向正常使用阶段进行过渡,以提高汽车的使用寿命.     

浅析气缸套早期磨损的原因及预防

气缸套早期磨损，是指发动机在磨合期内或使用很短时间内，气缸套已严重磨损的一种失效模式，会使发动机起动困难、漏气严重、功率不足、烧润滑油，甚至活塞和气缸套之间产生敲击声，有时会引起发动机严重拉缸和烧瓦。认真分析气缸套早期磨损的原因，采取预防措施，对于提高发动机的使用经济性有十分重要的意义。     

低温起动运转与发动机的磨损

我国设计生产的汽车一般都不是按照等强度设计,也就是说,当汽车的发动机已达到了使用极限,而它的底盘及其它部分还可能处于良好的工作状态,这时就需要送修。因此要延长汽车的使用寿命,实际上就是如何减少发动机的磨损。为了有效地提高零件的耐磨性,有必要研究发动机的磨损规律及各种因素对磨损的影响。     

低温起动运转与发动机的磨损

我国设计生产的汽车一般都不是按照等强度设计,也就是说,当汽车的发动机已达到了使用极限,而它的底盘及其它部分还可能处于良好的工作状态,这时就需要送修。因此要延长汽车的使用寿命,实际上就是如何减少发动机的磨损。为了有效地提高零件的耐磨性,有必要研究发动机的磨损规律及各种因素对磨损的影响。影响发动机的磨损因素比较多,原因也比较复杂,磨损的过程是物理、机械、化学现象的综合,而每一种现象都与运动的性质、载荷、单位压力、滑动速度、摩擦表面温度等都有关系。特别是受到实验条件的限制,我们对许多零件的磨损机理尚未彻底弄     

红岩CQ30290汽车发动机早期磨损的原因分析

通过红岩CQ30290汽车上的康明斯发动机产生早期磨损的异常情况的分析研究,认为康明斯发动机在红岩汽车上出现早期磨损的主要原因之一是汽车制造厂在进行汽车总体设计时对发动机进气系统配套设计不合理。其次,用户对发动机进气系统的使用、保养不当也是造成发动机异常磨损的原因。     

红岩CQ30290汽车发动机早期磨损的原因分析

通过红岩CQ30290汽车上的康明斯发动机产生早期磨损的异常情况的分析研究,认为康明斯发动机在红岩汽车上出现早期磨损的主要原因之一是汽车制造厂在进行汽车总体设计时对发动机进气系统配套设计不合理。其次,用户对发动机进气系统的使用、保养不当也是造成发动机异常磨损的原因。     

柴油机磨合后的清洗保养和调整

新的或大修后的内燃机,都应进行磨合试运转,这段时间称为“磨合期”。在磨合期内,由于零件表面上存在着微观不平度,所以摩擦件间的磨损积屑较多。又因各杆件、板件和薄壁壳体件会产生微量塑性变形;螺钉、螺母受振动而松动,而使连接件连接松动。因此在磨合试运转结束后,应对     

发动机曲轴轴颈与轴瓦磨损及预防措施

曲轴轴颈-轴瓦副是发动机中的重要配合副，如果使用不当极易造成早期磨损和破坏。了解其磨损规律及造成异常磨损的原因，提出使用中如何进行预防的措施，对防止曲轴轴颈—轴瓦副的早期损坏具有重要意义。     

火电厂节能工作浅析

本文探讨了火电厂节能基本程序和工作方法,分析节能工作要从基础工作、技术创新、设备整治、燃烧管理等方面入手的论述.     

Geothermal energy in agriculture in Yugoslavia

SFR Yugoslavia has natural hot water springs practically all over its territory, indicating the presence of geothermal reservoirs underground. There is no final estimate of how much energy can be expected from this new resource, except for figures based on the results of studies and investigations.The first use of geothermal energy in Yugoslavia in numerous spas dates back to the 19th century. Some remarkable examples of central heating are known, but the most widespread use is in agriculture (in greenhouse heating, farm heating and drying of agricultural products).     

Energy conservation measures in an institutional building in sub-tropical climate in Australia

In this study, various energy conservation measures (ECMs) on heating, ventilating and air conditioning (HVAC) and lighting systems for a four-storied institutional building in sub-tropical (hot and humid climate) Queensland, Australia are evaluated using the simulation software called DesignBuilder (DB). Base case scenario of energy consumption profiles of existing systems are analysed and simulated first then, the simulated results are verified by on-site measured data. Three categories of ECMs, namely major investment ECMs (variable air volume (VAV) systems against constant air volume (CAV); and low coefficient of performance (COP) chillers against high COP chillers); minor investment ECMs (photo electric dimming control system against general lighting, and double glazed low emittance windows against single-glazed windows) and zero investment ECMs (reset heating and cooling set point temperatures) are evaluated. It is found that the building considered in this study can save up to 41.87% energy without compromising occupancies thermal comfort by implementing the above mentioned ECMs into the existing system.     

Uncertainties in decarbonising heat in the UK

Heating is arguably one of the most difficult sectors to decarbonise in the UK's energy system. Meeting the 80% greenhouse gas emission reduction target by 2050 is likely to require that heat related emissions of CO₂ from buildings are near zero by 2050, and there is a 70% reduction in emissions from industry (from 1990 levels). Though it is clear that the use of the natural gas network will reduce over time, recent modelling suggests a limited residual role for gas by 2050 to help meet peaks in heat demand. High levels of uncertainty about the way in which heat will be decarbonised present a number of challenges to policy makers. This paper will explore the risks and uncertainties associated with the transition to a low carbon heat system in the UK as outlined by the 4th carbon budget review. The potential impact of key uncertainties on the levelised costs of heat technologies and the development of energy networks are explored using a sensitivity analysis approach. Policy changes required to decarbonise the heat sector are also examined.     

Solar drying in sludge management in Turkey

Two main wastewater treatment plants in Bursa city in Turkey will start to operate and produce at least 27,000 tons of dry solids per year by the end of 2006. The purpose of this study was to investigate an economical solution to the sludge management problem that Bursa city would encounter. The general trend in Turkey is mechanical dewatering to obtain a dry solid (DS) content of 20%, and liming the mechanically dewatered sludge to reach the legal landfilling requirement, 35% DS content. This study recommends limited liming & solar drying as an alternative to only-liming the mechanically dewatered sludge. Open and covered solar sludge drying plants were constructed in pilot scale for experimental purposes. Dry solids and climatic conditions were constantly measured. Faecal coliform reduction was also monitored. The specially designed covered solar drying plant proved to be more efficient than the open plant in terms of drying and faecal coliform reduction. It was found that, if the limited liming & solar drying method was applied after mechanical dewatering instead of only-liming method, the total amount of the sludge to be disposed would be reduced by approximately 40%. This would lead to a reduction in the transportation, handling, and landfilling costs. The covered drying system would amortize itself in 4 years.     

Viscous heating in liquid flows in micro-channels

Many experimental works on forced convection through micro-channels evidenced that when the hydraulic diameter is less than 1 mm, conventional theory can no longer be considered as suitable to predict the pressure drop and convective heat transfer coefficients. This conclusion seemed valid for both gas and liquid flows. Sometimes the authors justified this claim by invoking “new” micro-effects. On the contrary, in this paper the explanation of the experimental results obtained for micro-channels in terms of friction factors will be researched inside the conventional theory (Navier-Stokes equations). In particular, this paper will focus on the role of viscous heating in fluids flowing through micro-channels. A criterion will be presented to draw the limit of significance for viscous dissipation effects in micro-channel flows. The role of the cross-sectional geometry on viscous dissipation will be highlighted and the minimum Reynolds number for which viscous dissipation effects can no longer be neglected will be calculated as a function of the hydraulic diameter and of the micro-channel geometry for different fluids. It will be demonstrated how viscous effects can explain some experimental results on the Poiseuille numbers in micro-channels, which recently appeared in the open literature.     

Energy consumption in rural transportation in India

Energy consumption in rural transportation has been computed, taking into account the energy embodied in vehicles or bullocks, as well as the fuels or feeds and food (of operators). Bullock cart transport consumes over four times more energy than vehicles. However, animal transport will continue to be preferred because of its availability.     

Leading-edge Technologies in Hydropower Development in China

After the implementation of the Reform and Opening-up Policy for a period of 40 years, the exploitation of China’s hydropower resources developed significantly. Through vast amounts of scientific and technological research and construction practices, China has accumulated abundant engineering experience with respect to the construction technologies required for 300-meter-high concrete arch dams, 200-meter-high roller-compacted concrete gravity dams, 200-meter-high concrete face rockfill dams, and 250-meter-high earth core rockfill dams, large-flow discharge and energy dissipation, huge underground cavern group constructions, complicated foundation treatments for high earth and rockfill dams and high and steep slope reinforcements. These series of technologies have now reached an international leading level. In the near future, these technical improvements will likely have broader application prospects and make greater contributions toward hydropower development both in China and across the world.