双燃料发动机与普通柴油机的技术经济对比分析

介绍了2000型柴油／天然气双燃料发动机的技术特点,以及双燃料发动机与普通柴油机的区别,并以配备DJ40钻机动力为例,从经济效益方面对双燃料发动机与普通柴油机进行了比较分析,最终为优选双燃料发动机提供依据。     

使用双燃料发动机与普通柴油机作钻机动力的经济性分析

本文简要介绍2000型柴油,天然气双燃料发动机的技术特点,以及双燃料发动机与普通柴油机的区别,并以配备DJ40钻机动力为例,从经济效益方面对双燃料发动机与普通柴油机进行了对比分析,最终为优选双燃料发动机提供依据.     

双燃料发动机(天然气/柴油)性能与排放的研究

以4102型柴油机为基础机，开发天然气／柴油双燃料发动机，试验研究引燃油量、喷油提前角对发动机排放和经济性影响，以及双燃料发动机与原柴油机性能和排放的比较。     

中速大功率双燃料船用发动机关键技术研究

以某型船用中速柴油机为基础,开展船用双燃料发动机关键技术研究。基于国内外先进柴油机及双燃料发动机技术,成功研发出具有自主知识产权的中速大功率双燃料发动机。配机试验表明:所研制的双燃料发动机功率和柴油机相当,NO_x 及CO₂排放明显降低;其动力性、总体经济性和排放性均优于纯柴油发动机。     

双燃料发动机放热率计算和试验分析

提出了一个描述双燃料发动机燃烧特性的多区模型,模型将气体燃料的燃烧和引燃柴油的燃烧分别进行考虑。建立了由实测示功图求解双燃料发动机放热率的微分方程式,开发了计算双燃料发动机燃烧放热规律的软件,并在一台生物质气-柴油双燃料发动机上与传统柴油机放热率计算模型进行了试验验证和对比。研究和试验结果表明,用传统柴油机分析方法计算双燃料发动机的放热率峰值偏大,所计算的缸内工质平均温度偏高,新模型计算的结果与实际情况更吻合。     

船用低速双燃料发动机燃烧循环及应用现状分析

介绍了船用低速双燃料发动机两种燃烧循环过程,以及双燃料发动机与一般柴油机结构的区别进行了介绍。以此为基础总结了两种燃烧循环的双燃料发动机零部件结构、性能及外围支撑的优缺点。对两种循环发动机的应用现状进行了分析。     

生物制气-柴油双燃料发动机燃烧及排放分析

采用气化炉热解气化各种农林废弃的生物质,得到可燃生物制气。将柴油机改制成双燃料发动机,用生物制气作为主要燃料,由柴油引燃。测量生物制气-柴油双燃料发动机在最大扭矩转速时的气缸压力及废气排放,分析燃烧特性及对排放物生成的影响,并对比分析柴油机与双燃料发动机的差别。     

沼气—柴油双燃料发动机的调速与供气系统的研究

本文就1105型柴油机改装成沼气一柴油双燃料发动机的调速与供气系统进行了研究。在理论分析的基础上进行了对比试验,提出了提高双燃料发动机代油率和热效率的方向,可供设计双燃料发动机调遣和供气系统时参考。     

柴油/天然气电控双燃料技术研究

针对双燃料发动机的特点介绍了电控双燃料系统的原理;并对所研究的双燃料发动机的失效模式及效应进行了分析。性能试验表明:在不对原柴油机喷油角度、压缩比等参数进行任何改动,只增加燃气供应系统和电控双燃料系统的情况下,在75%负荷下天然气的替代率达到83%,经济性好;同时,排放较纯柴油有较大的改善;发动机的排温、最高燃烧压力及调速性能与柴油机的相近。     

YC6108天然气/柴油双燃料改型发动机的性能研究

本文介绍CY6 10 8Q型柴油机改装为天然气 /柴油双燃料发动机的有关情况。试验研究结果表明 ,虽然对原机的改动不大 ,但改装后的双燃料发动机与原机相比 ,动力性却略有提高 ,排气烟度也大幅度地改善 ,油气转换方便、并具有良好的可操作性、安全性和可靠性 ,双燃料发动机的性能基本达到了设计目标     

基于LABVIEW的柴油／酒精双燃料发动机燃料控制装置的研究

针对目前柴油/酒精双燃料发动机燃料系混合比难于控制，导致柴油，酒精双燃料发动机的研究发展缓慢的现状，在不改变发动机供油系统的前提下，利用LABVIEW软件自带的虚拟仪器设计双燃料喷射系统，实现柴油，酒精混合比的人为控制。     

电控柴油天然气(双燃料)发动机性能研究

本文主要对电控柴油天然气(双燃料)发动机的台架试验性能进行了研究，试验时通过控制数字电磁阀脉宽来决定每循环进入气缸的燃气量，用少量柴油引燃，达到双燃料柴油机的性能。试验结果表明，燃料发动机的动力性能、综合排放性能得到改善；天然气的最高替代率85％以上。可见，压缩天然气采用电子控制多点顺序喷射这一先进技术，使发动机达到了较好的综合性能指标。     

低热值燃气-柴油双燃料发动机动力性能计算

推导了低热值燃气-柴油双燃料发动机动力性能计算公式,并对由单缸、四冲程、水冷、直喷式柴油机改装的生物制气-柴油双燃料发动机的动力性能进行了计算分析。结果表明：双燃料发动机能够达到原柴油机的动力水平;其动力性能随引燃油量的减小而降低;在新鲜空气充足的前提下,供给更多的燃气,双燃料发动机的动力性能增强;燃气替代率有一最大值,超过该值后,随替代率增大,动力性能急剧下降;燃气低热值越高,替代率便可越大。计算得出的生物制气-柴油双燃料发动机在标定点和最大转矩点的最大生物制气替代率和对应的燃气进气比,与试验结果相吻合。     

生物制气-柴油双燃料发动机放热规律试验研究

采用气化炉热解气化各种农林废弃的生物质,产生可燃生物制气,用作为以柴油引燃的双燃料发动机的主要燃料。测量生物制气-柴油双燃料发动机气缸压力,计算分析放热规律。双燃料发动机与燃用纯柴油时的发动机相比,燃烧始点延迟,最大燃烧压力降低,最大放热率和排气温度增加,后燃较严重。负荷增大时,双燃料发动机燃烧始点提前,最大燃烧放热率增高,最高燃烧温度升高,后燃较严重。供油提前角提前时,后燃减小,燃烧过程明显改善。     

Application of machine learning and Box-Behnken design in optimizing engine characteristics operated with a dual-fuel mode of algal biodiesel and waste-derived biogas

Waste-derived biogas and third-generation algal biodiesel are attractive alternative fuels to substitute fossil diesel in a diesel engine. However, using biodiesel as a pilot liquid fuel and biogas as the main fuel in a diesel engine is a complicated and highly non-linear process. The current study seeks to predict and optimize the combustion and exhaust emission characteristics of a variable compression dual-fuel combustion engine. Data from experiments were obtained at a variety of engine loads, compression ratios, pilot fuel injection pressures, and timings. A multi-layer perceptron network was employed to develop an Artificial Neural Network (ANN) based prognostic model using the experimental data. The developed prognostic model was used to estimate brake thermal efficiency, biogas flow rates, peak in-cylinder pressure, carbon dioxide, unburned hydrocarbons, oxides of nitrogen, and carbon monoxide. The predictive model's robustness is demonstrated by statistical metrics such as R (0.9723–0.988) and R² (0.9453–0.9761), Nash-Sutcliffe model efficiency (94–97%), and mean absolute percentage error (0.013–0.128%), Kling-Gupta efficiency (0.9548–0.9836), and Theil's U2 model uncertainty (0.162–0.368). To optimize the parameters of dual-fuel combustion, the Multi-Output Response Surface Methodology (RSM) was employed. The trade-off assessment between emission and efficiency using the desirability approach revealed that 84% engine load, 244 bar of fuel injection pressure, 28 °BTDC of injection timing, and 17.5 compression ratio are the best-operating conditions for the test engine. An experimental investigation was used to corroborate the RSM research findings, and errors were less than 9%. It was revealed that ANN-linked RSM is a good hybrid technique for modeling, prediction, and optimization of the performance of a dual-fuel engine.     

生物制气-柴油双燃料发动机NOx计算模型

采用气化炉热解气化各种农林废弃的生物质，产生可燃生物制气，作为双燃料发动机的主要燃料。双燃料发动机由单缸、四冲程、水冷、直喷式柴油机改装，生物制气通入发动机进气管，在进气过程中吸入气缸。在油滴蒸发准维燃烧模型的基础上，结合单区模型和详细化学反应动力学机理，建立生物制气-柴油双燃料发动机的NOx生成模型，计算结果与试验结果吻合较好。供油提前角提前，生物制气-柴油双燃料发动机NOx排放量增加；引燃柴油量减小时，NOx排放量减小。     

Effect of engine parameters and type of gaseous fuel on the performance of dual-fuel gas diesel engines—A critical review

Petroleum resources are finite and, therefore, search for their alternative non-petroleum fuels for internal combustion engines is continuing all over the world. Moreover gases emitted by petroleum fuel driven vehicles have an adverse effect on the environment and human health. There is universal acceptance of the need to reduce such emissions. Towards this, scientists have proposed various solutions for diesel engines, one of which is the use of gaseous fuels as a supplement for liquid diesel fuel. These engines, which use conventional diesel fuel and gaseous fuel, are referred to as ‘dual-fuel engines’. Natural gas and bio-derived gas appear more attractive alternative fuels for dual-fuel engines in view of their friendly environmental nature. In the gas-fumigated dual-fuel engine, the primary fuel is mixed outside the cylinder before it is inducted into the cylinder. A pilot quantity of liquid fuel is injected towards the end of the compression stroke to initiate combustion. When considering a gaseous fuel for use in existing diesel engines, a number of issues which include, the effects of engine operating and design parameters, and type of gaseous fuel, on the performance of the dual-fuel engines, are important. This paper reviews the research on above issues carried out by various scientists in different diesel engines. This paper touches upon performance, combustion and emission characteristics of dual-fuel engines which use natural gas, biogas, producer gas, methane, liquefied petroleum gas, propane, etc. as gaseous fuel. It reveals that ‘dual-fuel concept’ is a promising technique for controlling both NO_x and soot emissions even on existing diesel engine. But, HC, CO emissions and ‘bsfc’ are higher for part load gas diesel engine operations. Thermal efficiency of dual-fuel engines improve either with increased engine speed, or with advanced injection timings, or with increased amount of pilot fuel. The ignition characteristics of the gaseous fuels need more research for a long-term use in a dual-fuel engine. It is found that, the selection of engine operating and design parameters play a vital role in minimizing the performance divergences between an existing diesel engine and a ‘gas diesel engine’.     

双燃料发动机的结构改进及试验研究

对一台单缸双燃料发动机进行了负荷特性和外特性试验,测得发动机各性能参数,并将试验结果与发动机燃用纯柴油时测得结果进行了较全面的分析对比,以便综合评价双燃料发动机的动力性、经济性和排放性能,为双燃料发动机的性能研究奠定试验基础。     

Emissions from sawdust biomass and diesel blends fuels

Biomass producer gas presents a very promising alternative fuel to diesel since it is a renewable and clean burning fuel having similar properties to those of diesel. In this outline, a multi-cylinder diesel engine is experimentally optimized for maximum diesel savings, lower emissions, and without any excessive vibration of the engine using sawdust biomass as producer gas. Emission parameters of the double-fuel engine at diverse gas flow rates are contrasted with those of diesel at distinctive load conditions. The study brings out that the greatest diesel reserve happens to be 80% at 8 kW load without any engine issue in dual-fuel mode. Carbon monoxide (CO), hydrocarbon (HC), and carbon dioxide (CO₂) emissions in dual-fuel mode are more contrasted with diesel at all test extents. Smoke opacity and oxide of nitrogen (NO) emission values in dual-fuel mode are less contrasted with diesel.     

Use of hydrogen in dual-fuel engines

The dual-fuel method is the easiest and most flexible method for using hydrogen in a diesel engine. In this work, a conventional single cylinder, four-stroke diesel engine has been converted to work on the dual-fuel principle with hydrogen as the inducted fuel. The main objectives of the investigation were to determine the optimum proportions between hydrogen and diesel oil under various engine operating conditions and to study the combustion process in the engine under these conditions. The results show that very satisfactory dual-fuel operation with hydrogen is possible. The thermal efficiencies obtained were comparable with pure diesel operation and up to about half the engine's energy requirement could be derived from hydrogen. The chief problem noticed is that of knocking setting in well before the stoichiometric hydrogen-air ratio. This requires further research for rectification.