别墅建筑的几种空调设计方案

介绍了可用于别墅建筑的风冷式盛大热泵空调机组系统，风冷热泵冷水机组系统、等方案，指出应根据不同的能源和气候条件，     

Experimental study on fluidisation behaviour and pressure drop across the centrifugal fluidised bed with static geometry by varying inlets,inlet width and mass of bed particles

Centrifugal fluidised bed with static geometry (CFBSG) is the novel approach of fluidisation which has not yet attracted the attention of IC engine researchers to remove particulate matter. This requires necessitating an understanding of the nature of fluidisation and pressure drop in CFBSG. The present study describes an experimental study on the effect of a number of inlets, inlet width, and mass of bed particles silicon carbide (SiC) on fluidisation and pressure drop across the fluidised bed chamber using air as a medium. Low pressure drop and better partial fluidisation were observed for three- and four-inlet chambers, especially at a higher loading of bed particles. The accumulation of bed particles near inlet and outlet is also drastically reduced as the number of inlet increases. When compared to 5?mm inlet slot chambers, 3?mm inlet slot chambers for any inlet gives better fluidisation with higher pressure drop.     

Effect of intake air oxygen enrichment for improving engine performance and emissions control in diesel engine

Stringent emission regulations and health awareness about air pollution have led researchers to find alternative means of minimising emissions in diesel engines. In this article, the influence of oxygen enrichment is discussed to determine the effect on diesel engine performance, emission characteristics and combustion characteristics. Normal diesel and oxygen-enriched diesel are used in this experiment. The increase in oxygen concentration led to complete combustion, producing higher thermal efficiency and low harmful emissions. From the results, it is noted that oxygen-enriched diesel fuel showed reduction of CO, HC and smoke emissions, while NOx emission increased.

Abbreviations/Nomenclature DI: direct injection; NOx: oxides of nitrogen; O₂: oxygen; HC: hydrocarbon; PM: particulate matters; CO: carbon monoxide; CO₂: carbon dioxide     

Detailed analysis on injection timing retardation and simultaneous technology in a biodiesel-powered compression ignition engine

ABSTRACT

This detailed study focuses mainly on the reduction of oxides of nitrogen emissions from CI engines. It also discusses about other emissions and performance parameters. Injection timing retardation and simultaneous technology methods have been employed for controlling oxides of nitrogen emissions by many researchers. This review paper studies on injection timing retardation and simultaneous technology and its effects on various operating parameters carried out in a biodiesel-powered CI engines. The objective of this work is to find the significance of injection parameters such as retardation of injection timing and simultaneous technology on the various emission parameters. This paper also deals upon the various methods of retardation of injection timing and simultaneous technology to examine the emissions such as HC, CO, NO_x, smoke, and particulate matters. The present study showed that widespread review on CI engine emission characteristics in a CI engine fuelled with biodiesel blends.     

Combustion characteristics of the direct injection diesel engine fuelled with corn oil methyl ester

Petroleum-based fuels is a finite resource that is rapidly depleting. Consequently, petroleum reserves are not sufficient enough to last many years. In this research, an experimental investigation has been performed to give insight into the potential of biodiesel as an alternative fuel for direct injection (DI) diesel engines. The experimental work has been carried out to estimate the combustion characteristics of a single-cylinder, four-stroke, DI diesel engine fuelled with corn oil methyl ester (COME) and diesel blends. The COME was preheated to temperatures namely 50°C, 70°C and 90°C before it was supplied to the engine. The optimised preheated temperature of 70°C was chosen based on the higher brake thermal efficiency and lower specific fuel consumption. The performance, emission and combustion characteristics are evaluated by running the engine with COME and diesel blends at this preheated temperature. In this paper, the combustion characteristics are only discussed. The combustion characteristics such as ignition delay, maximum rate of pressure, heat release rate, cumulative heat release rate, mass fraction burned and combustion duration of COME methyl ester and diesel were evaluated and compared with neat diesel. The rate of pressure rise and maximum combustion pressure inside the cylinder were high for COME blends compared with neat diesel. The heat release rate of diesel is higher compared with COME blends. The ignition delay and combustion duration are decreased for COME blends compared with neat diesel. The cumulative heat release rate and mass fraction burnt of COME blends are higher than neat diesel.     

燃气内燃机发电机组在LNG接收站的应用

介绍了燃气内燃机发电机组的优点,结合工程实例,对燃气内燃机发电机组在 LNG接收站中应用的技术与经济性进行了探讨。     

基于ArcSDE的管网数据一体化管理的研究与应用

空间数据库引擎(SDE,Spatial Data Engine)作为中间件能较好地解决地理信息系统(GIS,Geographical Information System)中空间数据和属性数据统一存储和管理的问题。论文首先探讨了管线数据库的常用解决方案,再重点阐述了ArcSDE的数据库存储方法,最后通过实例详细论述了ArcSDE对管网空间及属性数据的一体化管理方法,对其他城市管网系统的建库工作提供了一定的参考价值。     

Research on Spray, Combustion and Emission Characteristics for DI Diesel Engine

For diesel engines,meeting future stringent ex-haust emission standards represents a big challenge,particularly with regardtothe NOxemission with re-quirements of reducingsmoke emission andi mprovingfuel economy.The commercial CFD code FIREserves as the modeling platformfor the engine devel-opment and design.During the past several decades,researchers have investigated various aspects to i m-prove the combustion process of conventional dieselengines so as to reduce the generation of polluta…     

微弧氧化技术在消防车发动机活塞上的应用

为提高消防车发动机活塞的耐磨性,延长其使用寿命,通过采用脉冲电源放电的方法,对普通汽车发动机活塞(ZL108)基体进行了微弧氧化处理,并对获得涂层的耐磨性进行了分析,给出了活塞装车运行的试验结果.这些结果表明:本试验为微弧氧化技术在消防车发动机活塞上的应用提供了理论依据及实践经验,具有很大的可行性.     

氨混合燃料体系的性能研究现状

氨不仅是一种成本低廉的化工原料,而且由于具有较高的能量密度、易于储运、燃烧不产生CO₂等优点被认为是一种有广泛应用前景的清洁燃料。氨燃料具有替代汽油、柴油等化石燃料的应用潜力,为解决环境污染和化石能源短缺等问题提供了新的途径。本文概述了氨燃料的理化特性、燃烧特性以及与多种材料的相容性,介绍了氨作为调合燃料的性能及应用研究进展,尤其对氨-汽油燃料、氨-柴油燃料、氨-正庚烷燃料等燃料体系的研究成果进行了总结。文章集中分析了氨作为发动机燃料的机遇和挑战,尤其指出了氨燃料的生产高能耗、毒性及腐蚀性、氨的燃烧缺陷等问题,并探讨了对应的解决方案。在碳达峰、碳中和的大背景下,氨燃料在我国的发展具有后发优势。