原 稿
A New Type Car -- Hybrid Electric Vehicle
With skyrocketing fuel prices and changes in weather patterns, many car manufacturers claimed to develop the kind of vehicles that will increase the mileage and reduce the emissions. Hybrid car is a kind of vehicle which can meet above requirements. A hybrid car features a small fuel-efficient gas engine combined with an electric motor that assists the engine.
The reasons of building such a complicated machine are twofold: to reduce tailpipe emissions and to improve mileage. Firstly, hybrid cars are good for the environment. They can reduce smog by 90 percent and they use far less gasoline than conventional cars. Meanwhile, hybrid cars burn less gasoline per mile, so they release fewer greenhouse gases. Secondly, hybrid cars are economical. Hybrid cars, which run on gas and electricity, can get up to 55 to 60 miles per gallon in city driving, while a typical SUV might use three times as much gas for the same distance! There are three reasons can mainly account for that: 1) Hybrid engines are much smaller than those on conventional cars. A hybrid car engine is to accommodate the 99% of driving time when a car is not going up hills or accelerating quickly. When extra acceleration power is needed, it relies on the battery to provide additional force. 2) Hybrid gasoline engine can shut off when the car is stopped and run off their electric motor and battery. 3) Hybrid cars often recover braking energy. Electric motors could take the lost kinetic energy in braking and use it to charge the battery. Furthermore, hybrids are better than all-electric cars because hybrid car batteries recharge as you drive so there is no need to plug in. Most electric cars need to be recharged every 50-100miles. Also, most electric cars cannot go faster than 50-60 mph, while hybrids can.
Hybrid cars bridge the gap between electric and gasoline-powered cars by traveling further and driving faster and hybrid gas-electric cars are proving to be a feasible alternative at a time of high gas prices. So, in my opinion, hybrid cars will have a bright future.
How Does Hybrid Electric Vehicle Work？
You probably own a gasoline or diesel-engine car. You may have heard of electric vehicles too. A hybrid vehicle or hybrid electric vehicle (HEV) is a combination of both. Hybrid vehicles utilize two or more sources of energy for propulsion. In the case of HEVs, a combustion engine and an electric motor are used.
How it works depends on the type of drive train it has. A hybrid vehicle can either have a parallel or series or parallel-series drive train.
Parallel Hybrid
The parallel hybrid car has a gas tank, a combustion engine, transmission, electric motor, and batteries.
A parallel hybrid is designed to run directly from either the combustion engine or the electric motor. It can run using both the engine and the motor. As a conventional vehicle, the parallel hybrid draws its power from the combustion engine which will then drive the transmission that turns the wheels. If it is using the electric motor, the car draws its power from the batteries. The energy from the batteries will then power the electric motor that drives the transmission and turns the wheel.
Both the combustion engine and the electric motor are used at the same time during quick acceleration, on steep ascend, or when either the engine or the motor needs additional boost.
Since the engine is directly connected to the wheels in a parallel drive train, it eliminates the inefficiency of converting mechanical energy into electrical energy and back. This makes a very effective vehicle to drive on the highway.
Series Hybrid
The series hybrid car also has a gas tank, a combustion engine, transmission, electric motor, and batteries with the addition of the generator. The generator can be the electric motor or it can be another separate component.
The series configuration is the simplest among the 3. The engine is not connected to the transmission rather it is connected to the electric motor. This means that the transmission can be driven only by the electric motor which draws its energy from the battery pack, the engine or the generator.
A hybrid car with a series drive train is more suited for city driving conditions since the engine will not be subjected to the varying speed demands (stop, go, and idle) that contributes to fuel consumption.
Series-Parallel Hybrid
The series-parallel configuration solves the individual problems of the parallel and series hybrid. By combining the 2 designs, the transmission can be directly connected to the engine or can be separated for optimum fuel consumption. The Toyota Prius and the Ford Escape Hybrid use this technology.
Honda’s hybrid
For those of you who have toyed with the idea of buying a hybrid but were discouraged by the price, you are not alone. In fact, despite the growing concern for the environment, not to mention the skyrocketing price of gas, hybrid cars still only represent a small percentage of global car sales, and a major reason for this is the cost.
Hybrids are considered the wave of the future because they not only reduce emissions, addressing the issue of climate change, but they get great gas mileage, an important consideration with the current price of oil. It should be noted that hybrids can also improve the power of the engine, which compromises any advantages in fuel efficiency and emissions. Whatever the application, however, the technology makes the cars more expensive.
Because of this, they are the vehicle of choice for only a small niche of people who can afford them, and they currently enjoy a special status amongst the image conscious celebrity-set. For most average consumers, however, they are not an option.
That may soon change.
Honda Motor Corporation, one of the largest car manufacturers in the world and a leader in fuel efficient technology, has unveiled it’s plan to introduce a low-cost hybrid by 2009. If they can pull it off, they hope to make the hybrid a more mainstream car that will be more appealing to the general public, with the ultimate goal of achieving greater sales and broader appeal than their current incarnation.
This, of course, is making Detroit nervous, and may signal a need for American car makers to start making greener and more fuel efficient vehicles, something they could afford to ignore in the past because hybrid cars weren’t worth their attention (due to such a small market share) while gas-guzzling SUVs have such high profit margins.
Honda, meanwhile, has had to confront a growing need to compete with Toyota, which has not only grown to be the world’s largest automaker, but makes the car that has become synonymous with the hybrid movement, the Prius. Honda is therefore faced with the seemingly insurmountable task of challenging Toyota’s dominance in the market.
Concurrently, Toyota is racing to lower production costs on the Prius, as well, which would hopefully result in a lower cost to the consumer. All eyes are on a potentially favorable car buyers market in 2009.
In the meantime, with even adamant global warming naysayers warming up (no pun intended) to the possibilities of an ecological disaster on the horizon, maybe it’s time that we got over our need to drive huge SUVs and start moderating our fuel consumption.
Then again, as gas prices hovering around $4.00 and with no ceiling in sight, we may have little choice in the matter.
Engine Operating Principles
Most automobile dngines are internal combustion, reciprocating 4-stroke gasoline engines, but other types have been used, including the diesel, the rotary ( Wankel ) , the 2-srtoke, and stratified charge.
Reciprocating means up and down or banck and forth, It is the up and down action of a piston in the cylinder blick, or engine block. The blick is an iron or aluminum casting that contains engine cylinders and passges called water jackets for coolant circulation. The top of the block is covered with the cylinder head. Which forms the combustion chanber. The bottom of the block is covered with an oil pan or oil sump.
Power is produced by the linear motion of a piston in a cylinder. However, this linear motion must be changed into rotary motion to turn the wheels of cars of trucks. The piston is attached to the top of a connecting rod by a pin, called a piston pin or wrist pin. The bottom of the connecting rod is attached to the crankshaft. The connecting rod transmits the up-and-down motion of the piston to the crankshaft, which changes it into rotary motion.
The connecting rod is mounted on the crankshaft with large beaings called rod bearings. Similar bearings, called main bearings, are used to mount the crankshaft in the block. Shown in Fig. 1-1
The diameter of the cylinder is called the engine bore. Displacement and compression ratio are two frequently used engine specifications. Displacement indicates engine size, and compression ratio compares the total cylinder volume to compression chamber volume.
The term stroke is used to describe the movement of the iston within the cylinder, as well as the distance of piston travel. Depending on the type of engine the operating cycle may require either two or four strokes to complete. The 4-stroke engine is also called Otto cycle engine, in honor of the German engineer, Dr. Nikolaus Otto, who first applied the principle in 1876. In the 4-stroke engine, four strokes of the piston in the cylinder are required to complete one full operating cycle. Each stroke is named after the action it performs intake, compression, power, and exhaust in that order, shown in Fig1-2.
1、Intake stroke
As the piston moves down, the vaporized mixture of fuel and air enters the cylinder through open intake valve. To obtain the maximum filling of the cylinder the intake valve opens about 10°before t.b.c., giving 20°overlap. The inlet valve remains open until some 50°after b.d.c. to take advantage of incoming mixture.
2、 Compression stroke
The piston turns up, the intake valve closes, the mixture is compressed within the combustion chamber, while the pressure rise to about 1Mpa, depending on various factors including the compression ratio, throttle opening and engine speed. Near the top of the stroke the mixture is ignited by a spark which bridges the gap of the spark plug.
3、 Power stroke
The expanding gases of combustion produces a rise in pressure of the gas to some 3.5Mpa, and the piston is forced down in the cylinder. The exhaust valve opens near the bottom of the stroke.
4、Exhust stroke
The piston moves back up with the exhaust valve open some 50°before b.d.d., allowing the pressure within the cylinder to fall and to reduce ‘back’pressure on the piston during the exhaust stroke, and the burned gases are pushed out to prepare for the next intake stroke.The intake valve usually opens just before the exhaust stroke.
This 4-stroke cycle is continuously repeared in every as long as the engineremains running.
A 2-stroke engine also goes through four actions to complete one operating cycle.
However, the intake and the compression actions are combined in one seroke, and the power and exhaust actions are combined in the other stroke. The term2-stroke cycle or 2-stroke is preferred to the term 2-cycle, which is really not accurate.
In automobile engines, all pistons are attached to a single crankshaft. The more cylinders an engine has, the more power strokes produced for cach revolution. This means that an 8-cylinder engine runs more smoothly bdcause the power atrokes are closer together in time and in degrees of engine rotation.
The cylinders of multi-cylinder automotive engines arranged in one of three ways.
1、Inline engines use a single block of cylinder.Most 4-cylinder and any 6-cylinder engines are of this design. The cylinders do not have to be vertical. They can be inclined either side.
2、V-type engines use two equal bands of cylinders, usually inclined 60degrees or 90degrees from the cach other. Most V-type engines have 6 or 8 cylinders, although V-4 and V-12 engines have been built.
3、Horizontally opposed or pancake engines have two equal banks of cylinders 180degreeas apart. These space saving engine designs are often air-cooled, and are found in the Chevrolet Carvair, Porsches, Subaus, and Volkswagens. Subaus design is liquid cooled.
Late-model Volkswagen vans use a liquid-cooled version of the air cooled VWhorizontally opposed engine.
译 文
新型汽车----混合动力汽车
在油价飞涨的今天，汽车制造商被要求发展一种排放低，行驶里程长的汽车。由此混合动力车诞生了。混合动力车的特征是拥有一个小型高效的发动机和一个辅助发动机的电动机。
发明这个复杂机器的原因是双重的：减少排放，增加形式路程。第一，混合动力车是环保的。混合动力车的排放比普通汽油机少90%。其间，混合动力车每英里的燃料消耗少，所以排放的二氧化碳也就少。第二，混合动力车是经济的。混合动力车是有发动机和电动机共同驱动的，每加仑燃料可以行使大约55~60英里，而普通的SUV行使相同的距离需要至少三倍的燃料！原因有三点：1）混合动力车的发动机排量比普通汽车的都小。当车不需要爬坡和急加速的情况下，发动机适应99%的驾驶情况。当需要额外的动力时，它可以通过发电机提供动力。2）混合动力车可以在怠速时使是发动机停止工作，而仅仅依靠电动机和电池驱动。3)混合动力车有能量回收装置。电动机可以在刹车时把能量回收，储存在电池中。此外，混合动力车要比纯电动车好，因为混合动力车不需要给电瓶另外充电。大部分纯电动车每行使50~100英里就要充电。而且，纯电动车的速度不能大于50~60英里每小时，而混合动力车可以。
混合动力车以它的低油耗和长行使距离填补了纯电动车和内燃机车之间的空隙，同时，在油价高涨的今天混合动力车被证明是一种可行的选择。因此，我认为混合动力车拥有一个光明的未来。
油电混合汽车是如何工作的？
您或许有辆汽油车或者柴油车。您或许也听说过电动汽车。一辆混合动力车或者是油电混合动力车是个能量的混合体。混合动力车有两个或两个以上的能量来源来推动汽车。在这种情况下，通常是由一个内燃机和一个电动机组成的。
那它是如何处理动力的联结方式呢？根据混合动力驱动的联结方式通常分为三类：并联式，串联式和混联式混合动力系统。
并联式混合动力系统
并联式混合动力系统式由供油系统，内燃机，变速箱，电机和电池组成的。
在并联式系统中，不管是内燃机还是电机都能各自驱动汽车，而且在某些情况下还能同时驱动汽车。当作为一辆普通汽车时，它的动力来自内燃机，并通过变速箱将动力传到车轮。如果用电动机驱动，它就会利用电池的能量，并通过变速箱传递给车轮。
当遇到急加速或上坡等需要额外的驱动力时，内燃机和电动机会同时工作，以满足需求。
当内燃机和并联式混合动力系统连接起来后，在使用的过程中的无用燃料消耗会大大减少，动力得到了回收，降低了内燃机油耗。当在平坦的路上行驶时，大部分时间是电动机在工作。
串联式混合动力系统
串联式系统同样拥有供油系统，发动机，变速箱，电动机和一个可以给电池充电的发电机。发电机可以是电动机也可以是另外一个独立的部分。
串联式系统可以说是这3种系统中最简单的了。发动机并没有和变速箱相连，而是和发电机连在一起。这意味着变速箱只能和电动机相连，而电动机的能量来自电池，发电机或者发动机。
一辆串联式混合动力车非常适和都市交通情况，使发动机避免了怠速和低速运转的工况，从而减少了油耗和排放。
混联式混合动力系统
混联式系统解决了并联和串联式各自的问题。由于结合了两种系统的优点，变速箱既可以和发动机连接，也可以和电动机相连，从而降低了油耗。丰田的Prius和福特的Escape Hybrid都是用的是这种 技术。
本田的混合动力技术
我们虽然想买混合动力的汽车但最终会被它的价格泼一盆冷水。事实上姑且不提飞涨的油价，另外就是我们很关心环境的，混合动力汽车还是由于价格原因只有很小的市场占有率。
混合动力被誉为下一个流行潮流，因为他不仅减少了给气候带来威胁的尾气排放，而且还解决了目前的高油价问题。值得一提是这还是内燃机协调燃料效能和排放方面技术进步的表现。不论如何应用，科技总是会使车的涨价。
就是因为这样，只有在一特殊的小市场里的少部分的人们可以买的起这样的车，他们在名人中有一种形象特殊的地位。对于大多数的人来说，他们不并不是一个选择。那种情况很快就会改变的。
全球最大的汽车生产商和燃料效能技术机构本田机车公司将要在2009年推出一款低价位的混合动力汽车。如果可以的话他们希望使这款车成为大众能接受的主流车型，达到更大的销售量并具有更广泛的吸引力的目标。
当然这样做会使底特律紧张起来，并给美国的汽车生产商们发出了一个信号：你们应该着手生产他们原来忽视的东西，那些更环保和燃油经济性更好的汽车了，在过去由于混合动力很少的市场占有率和高油耗svu车型有更大的利润使他们并不重视混合动力的研发。
现在本田不仅正在和全球最大的汽车制造商而且还是制造普锐斯---混合动力汽车的代名词的丰田公司来较量了。本田挑战一个看上去不可战胜被丰田掌控的市场。
同时丰田正致力于降低普锐斯的制造成本，从而降低其市场价格。所有的注意都集中在2009年的潜在的汽车消费市场。
于此同时，态度强硬的全球变暖的反对者更坚信生态灾难就要来临，或许已经是到结束我们对suv车型的钟爱，并着手降低成品油消费的时候了。
油价涨到了4美元并且还在无限制的增长，我们可能只有很小的选择空间了。
发动机工作原理
大多数汽车的发动机是内燃机，往复四冲程汽油机，但是也有使用其它类型的发动机，包括柴油机，转子发动机，二冲程发动机和分程燃烧发动机。
往复的意思就是上下运动或前后运动，在往复发动机中，气缸中活塞的上下运动产生发动机的动力，这种类型几乎所有的发动机都是依赖气缸体即发动机缸体，缸体是铸铁或铸铝制的，它包括发动机气缸和冷却液循环用的水套。缸体的顶部是气缸盖，它组成了燃烧室，缸体底部是油底壳。
气缸内活塞的直线运动产生动力，然而，必须将直线运动转化成旋转运动，使汽车车轮转动，活塞销将活塞连接在连杆顶部，连杆底部与曲轴连接，使汽车车轮转动，活塞销将活塞连杆顶部，连杆底剖与曲轴连接，连杆将活塞的往复运动传递给曲轴，曲轴将其转化为旋转运动，连杆是用连杆曲轴安装在曲轴上的，用类似的轴承即主轴承将曲轴固定在缸体内。
气缸的直径称为发动机的内径，排量和压缩比是两个常用的发动机参数 ，排量是指发动机的大小，压缩比是气缸总容积与燃烧室压缩容积之比。
术语: 冲程是用来说明活塞在气缸内的运动，也就是活塞行程的距离根据发动机类型的需要二冲程或四冲程来完成一个工作循环四冲程发动机也叫做奥托发动机，为了纪念德国工程 师奥托，他是在1876年第一个应用该原理的，在四冲程发动机中，要求气缸活塞四冲程来完成一个完整的工作循环，每个冲程根据其行为命名分别为: 进气冲程，压缩冲程，作功冲程和排气冲程。
1、进气冲程
当活塞下移时，雾化后的可燃混合气通过打开的进气门 进入气缸，为了达到最大的进气量，进气门在活塞到达上止点前10°打开，使进、排气门有20°打开重叠角，进气门一直打开到活塞到达下止点充分进入混合气之后50°左右。
2、压缩冲程
活塞开始向上移动时，进气门关闭，混合气在燃烧室中压缩，根据不同因素包括压缩比，节气门开度，发动机转速压力上升到约1兆帕，接近冲程顶部时，火花塞产生的电火花击穿点火间隙点燃可燃混合气。
3、作功冲程
燃烧膨胀的气体产生的压力上升到3.5个兆帕时，推动活塞下移，接近气缸底时，排气门打开。
4、排气冲程
随着排气门开启约下止点前50°，活塞回升，使气缸内压力下降在排气冲程，减少对活塞回压，派出废气，为下一个进气冲程作准备，通常情况下，进气门在排气冲程完成前打开。
只要发动机保持运转，每个气缸内四个冲程循环连续不断地重复下去。
两冲程发动机也同样通过四行程来完成，一个工作循环但是进气冲程，压缩冲程合为一个冲程，作功冲程形成另一个冲程，术语两行程循环和两行程就是所谓的术语双循环但实际上并不太准确。
在所用的汽车发动机中，所有的活塞都是固定在一个曲轴上的，气缸中发动机越多，每转为发动机的作功冲程产生越多的动力，这就意味着八缸发动机运转的越平顺，因为发动机在作功冲程中运转时间和旋转角度紧密。
多气缸发动机有三种排列形式，任其一种
1、直列式发动机用一个气缸体，大多数四缸发动机和一些六缸发动机都采用这种型式，这种气缸不必垂直分布，它们可以向任一方向倾斜。
2、V-型发动机用两排同样的气缸，通常夹角为60°或90°，大多数有六缸或八缸，尽管四缸和十二缸也有采用V型的。
3、 卧式或者对置式发动机有两排互为180°的气缸，这些节省窨发动机 设计 通常采用风冷式，在雪弗兰、富士、大众车采用这种型式，富士汽车采用水冷式，在顶置式风冷发动机中，大众的新型厢式汽车采用水冷式。
在未来的20年，内燃机仍是各种通用机械的主要动力，随着汽油和柴油的质量越来越高以及内燃机技术的快速发展，能量利用效率得到了明显的提高，同时代用燃料也会得到迅速运用，小型的废气涡轮增压内燃机的研制，必将对我国内燃机行业的发展及节约能源方面起到重要的作用。因此，如何结合我国国情来发展内燃机行业及中国的燃料，开发研究新的节能技术，制定科学的、符合发展的战略，是我国内燃机行业科研单位乃至国家政府必须重视的问题。
1．研究提高内燃机制造的关键技术
近几年我国通过技术引进和技术改造，内燃机技术已经有了长足的进步，走上了健康的发展之路。但在关键技术还远远落后于国外先进水平，所以，在关键技术上要加大科技投入，重点扶持油泵油嘴、增压器等关键零部件产业；充分利用电子控制、共轨系统等高新技术来改进内燃机及燃烧系统；解决整机开发及匹配技术，如柴油机燃油、进气及燃烧系统的匹配与优化技术；有计划的改进内燃机的制造工艺及材质的问题，提高内燃机的质量，增加能源利用效率，以达到节约能源的目的。
研究开发高速直喷燃烧系统。我国小型高速柴油机普遍采用涡流室，比直喷机型油耗高10％～15％。我国小型高速直喷柴油机处于研究开发阶段。
2．研究开发综合燃烧系统的内燃机
回顾内燃机发展历程，汽油机及柴油机都有各自的优点，而且已经表明汽油机与柴油机在互相渗透，扬长避短，为了适应燃料多元化及节约能源的要求，必须将汽油机及柴油机工作过程的优点综合在一起，研究开发新的综合燃烧系统。增加柴油机的均质预混合部分，取消汽油机的点火系统，增加压缩比；运用成熟的纳米材料及纳米技术。
3．研究及开发代用燃料
我国每年都需要进口大量的石油，而且逐年在增长，石油资源逐渐枯竭，所以必须考虑替代燃料，目前已经应用和发展了多元化的燃料，包括天然气(CNG)、液化石油气(LPc)、甲醇、乙醇、氢、二甲醚及生物柴油等，其中天然气、液化石油气、乙醇已经得到了应用，氢气是理想的清洁燃料，是科研人员追求的目标。目前，无论用水或生物质制氢，都是效率低、成本高，包括储存的一些技术仍远未解决。纳米材料及纳米技术有助于解决这一问题，但这需要较长时间的开发研究，宝马公司一直致力于氢气内燃机的研制，开发了多款氢内燃机汽车，其中V12氢内燃机是世界上首批用于轿车上的内燃机，该内燃机可使用氢气和汽油两种燃料；从20世纪80年代起国外就开始研究生物质能，不断取得一些成果，但仍未达到商业化的水平，据专家预测，2010年左右可达到廉价工业化要求。我国有关大学及科研单位也在进行研究、开发和应用生物质能及燃料，这是经济可持续发展的必由之路。
4．增压技术应该向中小功率内燃机发展
内燃机增压技术在上世纪60年代才获得了迅速的发展和广泛的推广使用，采用增压技术的内燃机可以降低油耗2％～5％，但目前大中型内燃机使用较多，而中小型的内燃机应用比较少。所以增压技术应向中小功率内燃机扩展，随着小型涡轮增压器结构的可靠性不断提高，我国应尽快开发小型废气涡轮增压汽油机及柴油机。
5．内燃机的柴油机化
内燃机作为最广泛的动力机械，其中我国汽油机占40％，其余为柴油机。柴油机的热效率比汽油机高，通常可以节油25％以上，这是世界上早已达成的共识。随着设计、制造技术、材料技术水平的提高，柴油机取代汽油机的技术障碍将逐步被克服，特别是近年“石油危机”以来，世界各国“柴油机化”迅速发展，不但农用发动机采用柴油机，各类机动车用发动机也采用柴油机，就是有些轿车也采用柴油机。