某轻型货车鼓式制动器设计含三维CATIA模型

喜欢就充值下载吧。。资源目录里展示的文件全都有，，请放心下载，，有疑问咨询QQ:1064457796或者1304139763 ==================== 喜欢就充值下载吧。。资源目录里展示的文件全都有，，请放心下载，，有疑问咨询QQ:1064457796或者1304139763 ==================== 题目：某轻型货车鼓式制动器设计某轻型货车鼓式制动器设计汇报内容汇报内容1.研究意义与国内外发展概况研究意义与国内外发展概况2.制动器的结构选择及方案分析制动器的结构选择及方案分析3.制动器的设计计算制动器的设计计算4.制动器主要零部件的结构设计制动器主要零部件的结构设计5.制动器主要零件的加工工艺制动器主要零件的加工工艺6.尺寸工艺链分析尺寸工艺链分析7.结论结论8.致谢致谢1.1 研究背景及意义研究背景及意义汽车使用越来越广泛，对制动性能要求也越来越高，而制动系故障引起的交通事故与日增多，所以目前急需要一种不仅可以完全发挥鼓式制动器制动效能因数高的优点，同时具有盘式制动器摩擦副压力分布均匀、制动效能稳定等优点的制动器；制动器是制动系中最主要零部件之一,它的设计制造对制动系的制动性能和稳定性有很大的影响；因此，本次设计是针对鼓式制动器来进行设计。1.2国内外现状及发展国内外现状及发展目前很多发动机排量较小的中低档车型，其制动系统大多采用“前盘后鼓式”，比如常见的大众捷达、长安铃木奥拓、东风悦达起亚千里马以及上海通用赛欧等。另外，鼓式制动器还用在一系列货车上。所以，鼓式制动器的设计制造水平很重要。虽然领从蹄式制动器的效能及稳定性在各式制动器中均处于中等水平，但由于其在汽车前进和倒车时的制动性能不变，结构简单，造价较低，也便于附装驻车制动机构，易于调整蹄片与制动鼓之间的间隙。所以，本次设计选择领从蹄式制动器。2.制动器的结构选择及方案分析制动器的结构选择及方案分析3.1.参考车型的参数：3.制动器的设计计算制动器的设计计算3.2 制动力与制动力分配系数 在 汽车进行制动的时候，在踏板力相对来说比较小时，地面的制动力FB与制动器的制动力Ff是近似相同的，地面制动力最大只能和地面附着力一样大，但是制动器的制动力只与踏板力有关，从理论上来说可以是无限大，因此当踏板力达到一个定值后，即图中的交点时，如继续加大制动器制动力，接着踩踏板时，就会出现车轮不转的情况，车轮就会出现抱死：（1）前轮先抱死，然后后轮再抱死；（2）后轮先抱死，然后前轮再抱死；（3）前、后轮同时抱死，这种情况的附着条件利用得最好。=3.3 同步附着系数 图中实际前后制动器制动力分配线与I曲线交于B点，可求出B点处的附着系数，则交线处的附着系数为同步附着系数。所以，同步附着系数选取0.774。3.4 行车制动（制动距离）制动距离s=31.04m 由上表算得的制动距离，=36.60m 因为，算得的制动距离小于表格规定的最大制动离，所以该制动系的行车效能满足要求。4.1 制动鼓 1.制动鼓直径D 轮辋直径为13英寸，货车的D/Dr一般在0.70-0.83，所以取 D/Dr=0.73，得：Dr=13*25.4=330.2mm D=0.73*330.2=241.05mm 根据QC/T3091999制动鼓工作直径及制动蹄片宽度尺寸系列的规定，制动鼓直径等于240mm；2.本设计采用由钢板冲压成形的辐板与灰铸铁鼓筒部分铸成一体的组合式制动鼓，制动鼓壁的厚度一般在13-18mm之间，选取13mm。4.制动器主要零件的结构设计制动器主要零件的结构设计4.2 制动蹄 1.本设计制动蹄采用热轧钢板冲压焊接制成，腹板和翼缘的厚度货车约为5-8mm,选取6mm；2.制动蹄的支承：采用偏心支承销，可以使一个自由度的制动蹄的工作表面与制动鼓的工作表面同轴心；3.制动蹄支承点位置坐标：k=0.2R=24mm，c=96mm。4.3 摩擦衬片 1.本次设计摩擦片采用着模压材料，它是以石棉纤维为主并与树脂粘结剂、调整摩擦性能的填充剂，摩擦系数f=0.3；2.摩擦片的包角 通常在90到120度之间选取，虽然包角减小有利于散热，但单位压力过高将加速磨损。实际上包角两端处单位压力最小，过大不仅不利于散热，而且易使制动作用不平顺，甚至可能发生自锁。所以，选取 =95度，根据QC/T3091999制动鼓工作直径及制动蹄片宽度尺寸系列，选取宽度 b=50mm，起始角 =42.5度；3.一个制动器的摩擦面积为198.87cm2。4.4 制动底板 制动底板是除制动鼓外制动器各零件安装基本，应保证各安装零件相互间位置地正确，它承受着制动器工作时的制动反力矩，应有足够的刚度。因此，本设计制动底板采用热轧钢板冲压成形，制动底板的厚度一般为2.6-5.8mm之间，选取5mm。4.5 制动轮缸 轮缸的缸体由灰铸铁HT250制成，其缸筒为通孔，采用两个活塞推动。1.轮缸直径：公式 =18.74mm，根据 GB 752487标准规定的尺寸系列中，选取轮缸直径为22mm；2.轮缸工作容积:=1519.76 3.轮缸活塞宽度22mm 4.缸筒壁厚6mm。4.6制动器间隙的调整机构 在未制动的状态下，制动鼓与摩擦衬片之间应有工作间隙，以保证制动鼓能自由转动。一般鼓式制动器的设定间隙为0.20.5mm。考虑到在制动过程中摩擦副可能产生机械和热变形，所以制动器在冷却状态下的间隙应通过试验来确定。另外，制动器在工作过程中会因为摩擦衬片的磨损而加大，因此制动器必须设有间隙调整机构。5.制动器摩擦片的加工工艺制动器摩擦片的加工工艺摩擦片加工的标准：螺栓锪孔后的剩余厚度应为摩擦片厚度的1/3，连合后的摩擦片贴合牢固，无裂损，不得有大于0.15的缝隙；光磨后的摩擦片螺栓头应低于摩擦片表面3以上，与制动鼓的接触面积应大于50，并保证两端首先接触；摩擦片的连接应从摩擦片的中部依次向两端拧紧螺栓，连接后的摩擦片与制动蹄应全部贴合，连接牢固，连接后蹄架进行油漆处理。摩擦片车削时要做到定位准确，圆跳动符合要求，圆跳动大于1时就要检查蹄片及定位情况，必要时更换蹄架；加工后，还应检查与制动鼓切合情况，保证摩擦片与制动鼓有较大的切合面积。检查工艺：先在制动鼓上涂以白粉，将摩擦片贴合在制动鼓上来回移动，检查切合情况，切合面积不小于摩擦片总面积的50%，且两端向中间分布，两端切合较重，中间较轻。6.尺寸工艺链分析尺寸工艺链分析图中，A1为增环，A2,A3为减环，间隙A0为封闭环。1验证各环基本尺寸：A0=A1-(A2+A3）=120(110+10)=0mm 2求各组成环平均公差：Tav=T0/(n-1)=0.1 3.调整各组成环公差：选A3为协调环，调整A3公差 T1=0.040(mm),T2=0.035(mm)那么，T3=0.025，则A3的公差等级为IT8，这样将容易通过切削加工来保证。7.结论结论1.通过对给定汽车制动系统的结构分析与设计计算，认识制动系各部分结构的功能和作用，了解现阶段使用状况以及普遍存在的问题，提升了我对汽车制动系统更全面的认识；2.制动系统是汽车中一个重要的总成，它既可以让行驶中的汽车减速与制动，又能保证停车后的汽车能停驻原地。制动系统工作可靠、制动性能优良的汽车能充分发挥出其高速行驶的动力性并保证行驶的安全性。这显示出了制动系统是汽车非常重要的组成部分，从而对于汽车制动系统的设计也显得非常的重要。谢辞谢辞请各位老师，同学批评指正请各位老师，同学批评指正 设 计 任 务 书 （理工类） 题 目： 某轻型货车鼓式制动器设计 学生姓名： 学 号： 专 业： 年 级： 学 院： 指导教师： 设计任务与要求： 设计任务： 1.通过合理整合已有的设计，阅读大量参考文献和设计标准，掌握机械设计的基本步骤和要求，以及传统机械制图的步骤和规则，掌握鼓式制动器总成的相关设计方法，以进一步扎实汽车设计基本知识，完成开题报告和设计说明书； 2.学会用AUTO CAD,CATIA等软件进行基本的建模和制图，完成鼓式制动器零件图以及装配图的绘制（3张0#图纸的工作量），同时提高分析问题及解决问题的能力。提出将各种设计方法互相结合,针对不同的设计内容分别应用不同的方法,以促进其设计过程方法优化、设计结果精益求精。 通过各种渠道大量搜集有关汽车鼓式制动器的资料信息，查阅国内外参考文献，查看汽车制动器的相关理论，了解汽车鼓式制动器的基本结构，认识鼓式制动器各部分结构的功能和作用，了解现阶段汽车鼓式制动器的使用状况以及普遍存在的问题，通过对其结构的分析和各种结构优缺点的比较，以及查阅相关标准，最后确定汽车鼓式制动器传动系的结构设计方案，对其主要结构零件进行参数选定、计算及校核，并为自己的设计方案做理论性验证，利用制图软件绘制出主要零部件的设计图纸和总装配图。根据设计车型的特点，合理计算该车型制动系统制动力及制动器最大制动力矩、鼓式制动器的结构形式及选择、鼓式制动器主要参数的计算与确定、摩擦衬块的磨损特性计算、制动器热容量和温升的核算、制动力矩的计算与校核、在AUTO CAD、CATIA等软件中完成鼓式制动器零件图以及装配图的绘制、合理性的分析和评价等。 推荐的主要参考文献和资料： [1] 齐志鹏. 汽车制动系统的结构原理及检修[M]. 北京: 人民邮电出版社, 2002. [2] 王望予. 汽车设计（第4版）[M]. 北京: 机械工业出版社, 2004. [3] 臧杰, 阎岩. 汽车构造[M]. 北京: 机械工业出版社, 2010. [4] 余志生. 汽车理论（第五版）[M]. 北京: 机械工业出版社, 2009. [5] 濮良贵, 纪名刚. 机械设计[M]. 北京: 高等教育出版社, 2006. [6] 汽车工程手册编辑委员会. 汽车工程手册: 设计篇[M]. 北京: 人民交通出版社, 2001. [7] 刘惟信. 汽车制动系统的结构分析与设计计算[M]. 北京: 清华大学出版社, 2004. [8] 全国轮胎轮辋标准化技术委员会. GB 9744-2007 载重汽车轮胎[S]. 北京：中国标准出版社, 2007. [9] 全国汽车行业标准委员会. QC/T309—1999 制动鼓工作直径及制动蹄片宽度尺寸系列的规定[S]. 北京: 中国标准出版社, 1999. [10] 国家标准局. GB 5763-1998 汽车用制动器衬片[S]. 北京: 中国标准出版社, 1998. [11] 国家质量技术监督局. GB 12676-1999 汽车制动系统结构、性能和试验方法[S]. 北京: 中国标准出版社, 1999. [12] [英]T. P. 纽康姆等. 汽车制动文集[M]. 吴植民, 李明丽译. 北京: 人民交通出版社, 1984. [13] 龚洪. 影响制动性能的因数及设计方法[J]. 汽车科技, 2003, (5): 20-22. [14] 王国权, 龚国庆. 汽车设计课程设计指导书[M]. 北京: 机械工业出版社, 2009. [15] 王伯平. 互换性与测量技术基础(第三版)[M]. 北京: 机械工业出版社, 2008. [16] 程国华. 汽车制动系统发展漫谈[J]. 汽车运用, 2003, (6): 21-22. [17] 刘彬. 汽车制动系统使用中的误区[J]. 汽车运用, 2003, (1): 25-26. [18] Rodolf Limpert. Brake Design and Safety (Second Edition)[M]. Warrendale, 1998. [19] Lijie Li, Huajiang OuYang, A. R. Abubakar. Numerical Analysis of Car Disc Brake Squeal Considering Thermal Effects[J]. Computational Mechanics, 2009: 399. 年 月 日 Open Access Journal Journal of Power Technologies 92(1)(2012)5567journal homepage:papers.itc.pw.edu.plEffect of hydrogen-diesel quantity variation on brake thermal efficiency of adual fuelled diesel engineBiplab K.Debnath,Ujjwal K.Saha,Niranjan SahooDepartment of Mechanical Engineering,Indian Institute of Technology GuwahatiGuwahati-781039,Assam,IndiaAbstractThe twenty first century could well see the rise of hydrogen as a gaseous fuel,due to it being bothenvironment friendly and having a huge energy potential.In this paper,experiments are performedin a compression ignition diesel engine with dual fuel mode.Diesel and hydrogen are used as pilotliquid and primary gaseous fuel,respectively.The objective of this study is to find out the specificcomposition of diesel and hydrogen for maximum brake thermal efficiency at five different loadingconditions(20%,40%,60%,80%and 100%of full load)individually on the basis of maximum dieselsubstitution rate.At the same time,the effects on brake specific fuel consumption,brake specificenergy consumption,volumetric efficiency and exhaust gas temperature are also observed at variousliquid gaseous fuel compositions for all the five loadings.Furthermore,second law analysis is carriedout to optimize the dual fuel engine run.It is seen that a diesel engine can be run efficiently inhydrogen-diesel dual fuel mode if the diesel to hydrogen ratio is kept at 40:60.Keywords:Diesel Engine,Diesel Replacement Ratio,Hydrogen,Dual Fuel,Efficiency,Second Law1.IntroductionThe use of conventional fossil fuels has reacheda perceived crisis point.A number of reasons areresponsible for this,such as finite reserves of whatare non-renewable energy sources and the damagefossil fuels cause to the environment 1.There-fore,researchers around the world are exploringevery option to find suitable alternatives to re-place fossil fuels,whether partially or fully 2.Some of the alternative fuels that have been usedto replace petroleum-based fuels include vegetableCorresponding authorEmail addresses:d.biplabiitg.ernet.in(BiplabK.Debnath),sahaiiitg.ernet.in(Ujjwal K.Saha),shockiitg.ernet.in(Niranjan Sahoo)oils,alcohols,liquefied petroleum gas(LPG),liq-uefied natural gas(LNG),compressed natural gas(CNG),bio gas,producer gas,hydrogen etc.Inthis context,hydrogen(H2),a non-carboniferousand non-toxic gaseous fuel,has attracted greatinterest and has huge potential.H2is only oneof many possible alternative fuels that can be de-rived from various natural resources.Others in-clude:coal,oil shale and uranium or renewableresources based on solar energy.H2can be com-mercially formed from electrolysis of water andby coal gasification;thermo-chemical decompo-sition of water and solar photo-electrolysis,al-though these are still in the developmental stageat present 3.The energy required to ignite H2is very low and thus its usage in spark ignitionJournal of Power Technologies 92(1)(2012)5567(SI)engines is not suitable.Again,in compres-sion ignition(CI)engines,H2will not auto ignitedue to its high auto ignition temperature(858 K).Therefore the dual fuel mode appears the bestway to utilize H2in internal combustion(IC)en-gines 4.The dual fuel environment can be cre-ated by initially using a small amount of diesel(as pilot fuel)to launch the combustion and thensupplying H2(as primary fuel)to deliver the restamount of energy to run the cycle.Regardingpower output,hydrogen enhances the mixturesenergy density at lean conditions during a dualfuel run by increasing the hydrogen-to-carbon ra-tio,and thereby improves torque at the wide openthrottle condition 5.H2can be supplied in theengine by carburation,manifold or port injectionor by cylinder injection 6,7.However,the injec-tion of H2in the intake manifold or port requires aminor modification in the engine and offers a bet-ter power output than carburetion 810.Theexperimental works of Yi et al.11 establishedthat intake port injection delivers higher efficiencythan in-cylinder injection at different equivalenceratios too.Varde and Frame figured out that the brakethermal efficiency(bth)of H2diesel dual fuel modeis primarily dependent upon the amount of H2added.The larger the amount of H2,the higherthe value of bthis 3,12.It has been seen in H2diesel dual fuel mode that 90%enriched H2giveshigher efficiency than 30%at 70%load,but can-not complete the load range beyond that due toknocking problems 3.However,bthwas foundto drop when the amount of H2is less than orequal to 5%.In their analysis,an extremely leanair H2mixture restricts the flame to propagatefaster,which lowers H2combustion efficiency 12.However,experimental works done later,with H2diesel dual fuel mode,do not prove this drop inbthwith H2addition as mentioned above 13.According to Shudo et al.hydrogen combus-tion causes higher cooling loss to the combustionchamber wall than hydrocarbon combustion,be-cause of its higher burning velocity and shorterquenching distance 14.A study performed byWang and Zhang indicates that the introductionof hydrogen into the diesel engine causes the en-ergy release rate to increase at the early stagesof combustion,which increases the indicated effi-ciency 15.This is also the reason for the low-ered exhaust temperature.According to them,for fixed H2supply at 50%,75%and 100%load,H2replaces 13.4%,10.1%and 8.4%energy respec-tively with high diffusive speed and high energyrelease rate.The practice of normal and heavy exhaust gasrecirculation(EGR)in H2diesel dual fuel modeis found to lower power production and fuel con-sumption 16.Increases in compression ratio(CR)for H2fuelled diesel engine improves power,efficiency,peak pressure,peak heat release rateand emission of oxides of carbon,but increasesNOxemission 17.A study of injection timingvariation shown that advancing injection timingalthough provides favorable emission reduction,but makes engine operation more inefficient andunstable 18.Sahoo et al.performed an experi-mental study on syngas diesel dual fuel mode forH2:CO ratio of 100:0 at 20%,40%,60%,80%and100%of full load at maximum possible supply ofhydrogen until knocking 19.The study revealsthat at 80%load,the engine offers a maximum19.75%brake thermal efficiency at a maximum72.3%diesel replacement ratio.A few researchers4,20 have studied the variation of H2-dieselquantity for constant diesel supply at each loadto improve the brake power(BP).The increasein the supply of H2in inlet manifold causes a re-duction in the air flow to the engine.As a result,the volumetric efficiency(vol)and consequentlythe bthof the engine reduces.Therefore,thereis scope to study and understand engine perfor-mance by varying both H2and diesel supply whilemaintaining constant BP at each load condition.In light of this fact,the objective of the presentstudy is to determine the best composition of H2-diesel for maximum bthby varying the quantity offuel(pilot and primary)and maintaining constantspeed and BP at each of the five load conditionscorrespondingly.Some of the important physicaland thermodynamic properties of diesel and H2are shown in Table 1.The load conditions selectedare 20%,40%,60%,80%and 100%of full load.As reported by Sahoo et al.19,the maximum 56 Journal of Power Technologies 92(1)(2012)5567Table 1:Properties of H2and diesel 19PropertiesDieselHydrogenChemical compositionC12H26H2Density?kgm3?8500.085Calorific value?MJkg?42119.81Cetane number4555Auto-ignition temperature(K)553858Stoichiometric air fuel ratio14.9234.3Energy density?MJNm3?2.822.87diesel replacement ratios during a dual fuel runare considered as 26%,42%,58%,72%and 44%atthe aforementioned loads respectively.Other per-formance parameters studied alongside are brakespecific fuel consumption(BSFC),brake specificenergy consumption(BSEC),voland exhaust gastemperature(EGT).In order to endorse the ex-perimental results and analysis,the Second Lawanalysis is performed to provide histograms of cal-culated availability of fuel,cooling water,exhaustgas,availability destruction and exergy efficiency.In this way,the present experimental and analyt-ical studies will establish the optimized quantityof H2-diesel composition for best efficiency at con-stant power at each load.2.Experimental setupThe experiments are carried out in a KirloskarTV1 CI diesel engine installed at the Centrefor Energy of the Indian Institute of Technol-ogy(IIT),Guwahati,India.Figure 1 shows aschematic diagram of the engine test bed.Theoriginal engine specifications are shown in Table 2.The engine loading is performed by an eddy cur-rent type dynamometer.The liquid fuel is sup-plied to the engine from the fuel tank through afuel pump and injector.The fuel injection sys-tem of the engine consists of an injection nozzlewith three holes of 0.3 mm diameter with a 120spray angle.A U-tube type manometer is used toquantity the head difference of air flow to the en-gine,while allowing the intake air to pass throughan orifice meter.The engine block and cylinderhead are surrounded by a cooling jacket throughwhich water flows to cool the engine.To mea-sure the specific heat of exhaust gas,a calorime-ter of counter flow pipe-in pipe heat exchanger isalso provided.Temperature measurement is per-formed by K-type thermocouples,which are fittedat relevant positions 21.In order to convert the diesel engine test bedinto dual fuel mode,some additional equipmentis installed in the setup.These include:hydro-gen gas cylinder with regulator,coriolis mass flowmeter,flame trap with fine tuning regulator,nonreturn valve(NRV)and gas carburetor.The cori-olis mass flow meter measures the mass flow rateof hydrogen;while the flame trap and the NRV areused to prevent fire hazards due to accidental en-gine backfire.In the dual fuel mode H2is suppliedto the engine by the induction method.In thismethod,H2mixes with the intake air in the inletmanifold outside the cylinder.A gas carburetor16 is fixed in the intake manifold of the engineto provide the H2supply.The liquid fuel supplyis controlled through a fuel cut offvalve for vari-ous diesel fuel replacement ratios by a lever-armarrangement,as shown in Fig.2.3.Experimental procedureTable 3 illustrates the designed experimental ma-trix of the H2-diesel test at different loads.Ini-tially,the engine is allowed to run on diesel atno load condition for a few minutes to attaina steady state.The cooling water supplies forthe engine and calorimeter are set to 270 and 57 Journal of Power Technologies 92(1)(2012)5567Table 2:Diesel engine specification 21ParameterSpecificationEngine typeKirloskar TV1General detailsSingle cylinder,four stroke diesel,water cooled,compression ignitionBore and stroke87.5110 mmCompression ratio17.5:1Rated output5.2 kW(7 BHP)1500 rpmAir boxWith orifice meter and manometerDynamometerEddy current loading unit,016 kgFuel injection opening205 bar 23BTDC staticCalorimeter typePipe in pipe arrangementRotameterFor water flow measurementTable 3:The experimental matrixLoadDiesel replacement ratioEngine operation20%10,20,26Speed:40%10,20,30,40,42150050 RPM60%10,20,30,40,50,58Injection timing:80%10,20,30,40,50,60,70,7223BTDC100%10,20,30,40,44Figure 1:Schematic diagram of the setup80 liters per hour,as per the engine provider in-structions.Thereafter,the load is gradually in-creased to 3.2 kg(20%load)and the engine is al-lowed to run until it reaches a steady state.Then,the inlet and outlet temperatures of engine cool-ing water,calorimeter cooling water and exhaustgas are measured.Water head difference,dieselFigure 2:Adjustable lever arm arrangementflow rate and engine speed are also recorded.Theadjustable lever arm is then rotated to press thefuel cut offvalve,which will reduce the fuel supplyand speed.The lever arm is then fixed at a point wherediesel supply is reduced by 10%.At this pointH2(99.99%purity)is allowed to flow from thehigh pressure cylinder to the flame trap,throughthe coriolis mass flow meter.At the outlet of theflame trap,one fine tuning regulator is connectedto control H2flow accurately and is delivered tothe intake manifold through the NRV and gas car-58 Journal of Power Technologies 92(1)(2012)5567buretor.The added supply of chemical energy inthe form of H2in the cylinder is converted into me-chanical energy after combustion.This increasesthe speed and BP of the engine.The quantity ofH2is adjusted precisely to return the engine speedand BP to its previous value,recorded during thepure diesel run.The pressure of the H2outlet isnot allowed to exceed 1.2 bar.After the enginereaches a steady state,the values of temperatures,water manometer head and mass flow of H2fromcoriolis flow meter are recorded.The H2supply isthen stopped and the adjustable lever depressedfurther to reduce the diesel fuel supply by 20%.At this point,H2supply is initiated and the pro-cedure is repeated.Once the data of all the fuel replacement ratiosare recorded,the engine is restored to its dieselmode.The load is increased by the eddy currentdynamometer,and the measurement procedurefor all the diesel replacement ratios are repeatedat that load.The maximum fuel replacement ra-tios(shown in Table 3)for five loading conditions(20%,40%,60%,80%and 100%of full load)aretaken from the work reported by Sahoo et al.19.Finally,the H2supply is stopped completely,andthe engine is allowed to run at“no load condition”prior to complete shutdown.4.Analysis procedureAfter collecting the data sets at each diesel re-placement ratio and for each load,the dependentparameters are calculated according to the follow-ing equations 22,23.The diesel replacement ratio(Z)is given byZ=md mpd md 100%(1)The brake power can be written asBP=2 3.142 N W r60000(2)The brake thermal efficiency for diesel mode ismeasured as(bth)diesel=BP md LHVd 100%(3)The brake thermal efficiency for dual fuel modeis given by(bth)dual=BP mpd LHVpd+mh LHVh 100%(4)The brake specific fuel consumption for dualfuel mode is computed fromBSFC=mpd+mhBP!3600(5)The brake specific energy consumption for dualfuel mode is given byBSEC=mpd LHVpd+mh LHVhBP(6)The volumetric efficiency can be computedfromvol=ma?kgs?3600?3.1424?D2 L Nn 60 K a 100%(7)5.Thermodynamic analysisThe results of the hydrogen-diesel dual-fuel ex-periment are analyzed using the Law of Ther-modynamics.It provides significant informationregarding the appropriate distribution of energysupplied by fuel in different parts of the engine24.Also,the energy that is utilized or destroyedis quantified through availability analysis.Thisanalysis,finally,gives the exact amount of hy-drogen and diesel composition which should bemaintained to extract the maximum amount ofenergy from the fuel energy supplied.Hence,the“First Law(Energy)”along with the“Second Law(Exergy)”study of the engine is described in thefollowing section with correct equations.5.1.Energy analysisAccording to the First Law of thermodynamics,the energy supplied in a system is conserved inits different processes and components 25.In aCI engine,the fuel energy supplied(Qi)is trans-ferred in its different processes,viz.Shaft power(Ps),Energy in cooling water(Qc),Energy in ex-haust gas(Qe)and Uncounted energy losses(Qu)59 Journal of Power Technologies 92(1)(2012)5567in the form of friction,radiation,heat transfer tothe surroundings,operating auxiliary equipments,etc.These different forms of energies are calcu-lated according to the following analytical expres-sions 26.The fuel energy supplied,i.e.,the energy inputcan be calculated as follows:(Qi)diesel=md3600 LHVd(8)(Qi)dual=mpd3600 LHVpd+mh3600 LHVh(9)The energy transferred into the shaft can bemeasured asPs=Brake power of the engine(10)The energy transferred into cooling water canbe computed asQC=mpd3600!Cpw(Two Twi)(11)The energy flow through exhaust gas can beestimated asQe=?me3600?Cpe(Tei Teo)(12)For a more precise thermodynamic analysis,thespecific heat of exhaust gas is calculated from theenergy balance of the exhaust gas calorimeter.Fi-nally,from the energy balance,the uncounted en-ergy losses can be estimated asQu=Qi(Ps+Qc+Qe)(13)5.2.Exergy analysisThe availability can be described as the abil-ity of the supplied energy to perform a usefulamount of work 27.In the CI engine the chem-ical availability of fuel(Ai)supplied is convertedinto different types of exergy,viz.,Shaft availabil-ity(As),Cooling water availability(Ac),Exhaustgas availability(Ae)and Destructed availability(Ad)in the form of friction,radiation,heat trans-fer to the surroundings,operating auxiliary equip-ments,etc.These forms of energies are calculatedaccording to the following analytical expressionsas described in the literature 2830.The chemical availability of the fuel supplied isgiven by(Ai)diesel=1.0338 md3600 LHVd(14)(Ai)dual=1.0338 mpd3600 LHVpd(15)+0.985 mh3600 LHVhThe availability transferred through the shaftis recorded asAs=Brake power of the engine(16)The cooling water availability can be measuredasAC=QC?mw3600?Cpw ln TwoTwi!(17)Exhaust gas availability can be calculated asAe=Qe+?mw3600?(18)To(Cpw ln ToTei!Re ln PoPe!)The exhaust gas constant(Re)is estimatedfrom the energy balance of the exhaust gascalorimeter and the products of complete com-bustion of the diesel fuel.The uncounted availability destruction is deter-mined from the availability balance asAd=Ai(As+Ace+Ae)(19)Therefore,the exergy efficiency(II)can be es-timated asII=1 DestructedavailabilityFuelavailability=1 AdAi(20)6.Results and discussionThe results and discussion part of this H2-dieseldual fuel experiment work is divided into two sec-tions;viz.,performance analysis and Second Lawanalysis.The performance analysis discusses bth 60 Journal of Power Technologies 92(1)(2012)5567 05101520251020304050607080Diesel Replacement(%)20%Load40%Load60%Load80%Load100%LoadFigure 3:Variation of brake thermal efficiency with dieselreplacement 0.20.40.60.81.01.21.41020304050607080Diesel Replacement(%)20%Load40%Load60%Load80%Load100%LoadFigure 4:Variation of brake specific fuel consumption withdiesel replacement,BSFC,BSEC,vol,EGT and a comparison ofmaximum brake thermal efficiencies for diesel anddual fuel modes.Later on,the Second Law anal-ysis shows the availabilities of fuel,cooling waterand exhaust gas,destroyed availability and exergyefficiency.6.1.Performance analysisThe effect of variation of H2-diesel quantity onbthfor the five loading conditions is shown inFig 3.Except for the 20%load,all other load-ing conditions show that an increase in H2quan-tity increases bth,but only up to a certain limit.This indicates that in the lower load region,H2cannot burn properly with diesel and results inpoor combustion efficiency.However,this con-dition improves with the increase in load.Themaximum value of bthobtained is around 20%at 0.640.660.680.700.721020304050607080Diesel Replacement(%)20%Load40%Load60%Load80%Load100%LoadFigure 5:Variation of volumetric efficiency with diesel re-placement 481216201020304050607080Diesel Replacement(%)20%Load40%Load60%Load80%Load100%LoadFigure 6:Variation of brake specific energy consumptionwith diesel replacement80%load condition for both 50%and 60%dieselreplacement ratio.Along with the increase in thebththere is also a reduction in BSFC encounteredwith the increase in load and H2substitution rate(except for the 20%load)which is exemplifiedin Fig.4.This is because with the increase inH2,the quantity of energy supply rate into thecylinder increases.Therefore,the total amountof fuel needed for the same BP is alleviated asfar as energy supply is concerned.However,af-ter a certain point of H2replacement,the enginemay not run more efficiently,resulting in a reduc-tion in bth.This is because of the large reductionin volumetric efficiency caused by a reduction ofair(or more precisely oxygen)accessibility insidethe cylinder.This can be clearly understood fromFig.5.The reduction in BSEC with the increase 61 Journal of Power Technologies 92(1)(2012)5567 1002003004005006007008009001020304050607080Diesel Replacement(%)20%Load40%Load60%Load80%Load100%LoadFigure 7:Variation of exhaust temperature with dieselreplacement 051015202520406080100Eng