在内燃机中掺烧甲醇新方式的试验研究

一种在柴油机上有效地掺烧甲醇的新方式,在495涡流燃烧室柴油机上已试验成功。当甲醇掺烧比不大于30%时,柴油机在各种工况下,折合油耗率比燃用纯柴油时低。这一效果,尤其低负荷时油耗率低是目前其他掺烧方式尚无法实现的。论文就掺烧甲醇蒸气的燃烧过程、新方法的特点以及与化油器熏蒸法的比较,进行了较深入的分析探讨。     

甲醇燃料在船舶内燃机动力中的应用

针对现有船舶动力应用甲醇燃料的方式,从甲醇的特点、甲醇混合气的形成、燃烧模式等方面开展分析,结果表明：高速船用柴油机改装为点燃式甲醇燃料发动机简便易行;低速船舶内燃机缸径大、缸盖空间充裕,便于多喷嘴布置,实现缸内直喷微量燃油引燃、甲醇燃料压燃模式,可在满足排放法规要求的前提下,在双燃料及纯燃油模式间切换;中高速船舶内燃机缸盖结构紧凑,适合采用柴油在缸内与甲醇混合气共燃的模式。     

内燃机燃用甲醇的研究进展和发展前景

介绍了甲醇的特点及作为代用燃料的优势,详细综述了甲醇作为发动机燃料的各种燃用方式的研究进展,并对甲醇燃料在内燃机中的应用前景及存在的问题进行了探讨。     

内燃机燃用甲醇的研究进展和发展前景

介绍了甲醇的特点及作为代用燃料的优势,详细综述了甲醇作为发动机燃料的各种燃用方式的研究进展,并对甲醇燃料在内燃机中的应用前景及存在的问题进行了探讨.     

甲醇燃料在车用发动机上的应用研究

结合甲醇燃料的理化特性,分别在495Q和JT468Q汽油发动机进行了燃用高比例M85甲醇汽油燃料和全甲醇燃料的对比试验。试验结果表明：直接燃烧定比例甲醇燃料时,功率和扭矩都略有提高;提高压缩比后,功率和扭矩都大幅度提高,燃油消耗也大幅度降低、排放明显改善。     

激光光声光谱法检测甲醇内燃机燃烧排放气体成分的研究

介绍激光光声光谱法检测以甲醇为燃料的内燃机燃烧排放的气体成分,证明了激光光声光谱气体分析装置是内燃机燃烧诊断的有效工具之一。     

废热重整甲醇内燃机-涡轮复合循环

介绍了一种清洁、高效的废热甲醇重整气涡轮-内燃机复合动力循环,研究了甲醇操作压力、水醇比、压缩比及过量空气系数对循环热效率的影响,并与氢气机、甲醇机、汽油机进行了对比分析。     

废热裂解甲醇内燃机复合循环研究

介绍了一种利用发动机废热裂解甲醇,将裂解气引入涡轮膨胀冷却后燃烧的新型循环,并建立物理数学模型,利用SHBWR方程及其混合规则描述流体及流体混合物状态,研究了甲醇操作压力、操作温度等对甲醇裂解气作功能力的影响,讨论了裂解气涡轮与发动机耦合时的调节与优化。     

煤基甲醇和天然气基甲醇燃料的生命周期影响评价

用生命周期评价方法,对煤基M85(甲醇体积占85%的甲醇汽油混合燃料)和天然气基M85的生命周期环境影响进行评价。结果表明:与汽油相比,煤基M85和天然气基M85燃料的环境影响总水平值分别降低了41.2%和60.8%。在污染物中,VOC排放产生的环境影响最大。煤基M85的SO2排放高于天然气基M85,导致煤基M85对环境影响总水平值高于天然气基M85。煤制甲醇CO变换工艺造成的CO2排放占煤基M85全生命周期CO2排放的36%,导致其生命周期内的温室气体排放高于汽油和天然气基M85。     

A quasi-dimensional model for the power cycle of a hydrogen-fuelled ICE

There is a growing body of literature as well as increased demonstration of advanced hydrogen-fuelled internal combustion engines. These engines offer the potential of high power output, outperforming gasoline engines; high efficiency, approaching or bettering diesel engines; and very low emissions well within the most strict emission standards.     

Micro-/nanoscaled irreversible Otto engine cycle with friction loss and boundary effects and its performance characteristics

An irreversible cycle model of the micro-/nanoscaled Otto engine cycle with internal friction loss is established. The general expressions of the work output and efficiency of the cycle are calculated based on the finite system thermodynamic theory, in which the quantum boundary effect of gas particles as working substance and the mechanical Casimir effect of gas system are considered. It is found that, for a micro-/nanoscaled Otto cycle devices, the work output W and efficiency η of the cycle can be expressed as the functions of the temperature ratio τ of the two heat reservoirs, the volume ratio r_V and the surface area ratio r_A of the two isochoric processes, the dimensionless thermal wavelength λ and other parameters of cycle, while for a macroscaled Otto cycle devices, the work output W₀ and efficiency η₀ of the cycle are independent of the surface area ratio r_A and the dimensionless thermal wavelength λ. Further, the influence of boundary of cycle on the performance characteristics of the micro-/nanoscaled Otto cycle are analyzed in detail by introducing the output ratio W/W₀ and efficiency ratio η/η₀. The results present the general performance characteristics of a micro-/nanoscaled Otto cycle and may serve as the basis for the design of a realistic Otto cycle device in micro-/nanoscale.     

工质变比热和传热损失对Otto循环性能的影响

用有限时间热力学的方法分析空气标准Otto循环，由数值计算给出了存在传热损失和工质变比热时循环功率与压缩比、效率与压缩比以及功率和效率的特性关系，并分析了传热损失和工质变比热对循环性能的影响特点。通过分析可知传热和变比热特性对Otto循环性能有较大影响，所以在实际循环分析中应该予以考虑。     

Optimization of the endoreversible otto cycle with respect to both power and mean effective pressure

The output response of an endoreversible Otto cycle with combustion is optimized with respect to both power and mean effective pressure. The endoreversible cycle is one in which the heating process by combustion and the heat removing process to the surroundings are the only irreversible processes in the cycle. Expressions for these two responses are derived and optimized and a comparative analysis of results conducted. This paper provides an additional criterion for use in the evaluation of the performance and the suitability of an Otto engine.     

A comparison of Miller and Otto cycle natural gas engines for small scale CHP applications

This paper presents an investigation into the feasibility and potential advantages of a small scale Miller cycle natural gas engine for applications such as domestic combined heat and power systems. The Miller cycle engine is compared to a standard Otto cycle engine using cycle analyses and multidimensional simulation, and basic engine design implications are discussed. It is found that the Miller cycle engine has a potential for improved fuel efficiency, but at the cost of a reduced power to weight ratio. A fuel efficiency advantage of 5→10%$5\to 10\%$ compared to a standard Otto cycle engine appears possible, however it is stated that further investigations, in particular into the topic of engine friction, are required in order to validate the findings.     

Comparison of biodiesel production from crude Jatropha oil and Krating oil by supercritical methanol transesterification

This work compared the production of biodiesel from two different non-edible oils with relatively high acid values (Jatropha oil and Krating oil). Using non-catalytic supercritical methanol transesterification, high methyl ester yield (85–90%) can be obtained in a very short time (5–10 min). However, the dependence of fatty acid methyl ester yield on reaction conditions (i.e., temperature and pressure) and the optimum conditions were different by the source of oils and were correlated to the amount of free fatty acids (FFAs) and unsaturated fatty acid content in oils. Krating oil, which has higher FFAs and unsaturated fatty acid content, gave higher fatty acid methyl ester yield of 90.4% at 260 °C, 16 MPa, and 10 min whereas biodiesel from Jatropha oil gave fatty acid methyl ester yield of 84.6% at 320 °C, 15 MPa and 5 min using the same molar ratio of methanol to oil 40:1. The product quality from crude Krating oil met the biodiesel standard. Pre-processing steps such as degumming or oil purification are not necessary.     

内燃机复杂零件结构分析的实用边界元方法

给出了一种适用于内燃机复杂零件结构分析的简便、高精度三维边界元算法,它对非均匀、非规则网格,特别是快速疏密过渡以及含有狭长单元的网格能获得较好的计算精度,从而可放宽对内燃机复杂零件边界元网格划分的要求,对简化数据准备工作、降低计算规模和节省计算时间,以及提高计算精度等具有重要的实际意义,最后以曲轴三维边界元分析为例进行了说明。