(Single overhead camshaft engine) Engine type divided by number of camshaft positions, SOHC stands for single overhead camshaft engine, which is suitable for 2-valve engines.
(Double overhead camshaft engine) indicates a double overhead camshaft engine that is suitable for multi-valve engines. Usually engine has 2 valves per cylinder, and in recent years 4-valve and 5-valve engines have also appeared, which undoubtedly opens way for improved intake efficiency and engine power at high speeds. This type of engine is suitable for high speed engines and can properly reduce fuel consumption at high speeds.
Turbo, abbreviated as T, is usually 1.8T, 2.8T, etc. at rear of car. A turbocharger has a single turbocharger and a dual turbocharger. Turbocharging, which we commonly refer to as exhaust gas turbocharging. Generally, exhaust gases drive an impeller that drives impeller, and more air is sent into engine, thereby increasing engine power. reduction in engine fuel consumption.
(Electronic Valve Timing and Lift Control) Honda's VTEC is world's first valve control system that can simultaneously control valve opening and closing times and lift in two different situations. It has evolved into i-VTEC. The biggest difference between an i-VTEC engine and conventional engines is that for low to medium speeds and high speeds, two sets of different valve-driven cams are used, which can be switched automatically via an electronic system. In addition, engine can also automatically change opening time and valve lift degree according to driving conditions, that is, change intake air amount and exhaust amount, so as to achieve purpose of increasing power and reducing fuel consumption.
(Intelligent Variable Valve Timing and Lifting) i-VTEC is English abbreviation for Honda's Intelligent Variable Valve Timing System. Newer Honda sedan engines typically have i-vtec systems installed. Honda's i-vtec system continuously adjusts valve timing and can control valve lift. Its working principle is as follows: when engine is switched from low speed to high speed, electronic computer automatically supplies engine oil to small turbine in intake camshaft drive gear, so that under pressure, small turbine is opposite. The gear turns at a certain angle, so that camshaft turns forward or backward in range of 60 degrees, thereby changing opening timing of intake valve and achieving goal of continuously adjusting valve timing.
(Stepless Variable Valve Timing System) South Korea's automotive industry has never been known for advanced technology, so most of technologies used are based on experience of Germany, Japan and other countries, and CVVT is precisely in VVT-i and i-Developed on basis of VTEC. Take for example Hyundai CVVT engine, which can be started based on speed to achieve goal of increasing power and reducing fuel consumption. But CVVT will not control valve lift, which means this engine only changes intake and exhaust timing.
(Variable Valve Timing Engine) This system adjusts engine cam phase with equipped control and execution system, so that valve opening and closing time changes with engine speed change, so as to improve charging efficiency, so as to increase engine power.
(Intelligent Variable Valve Timing) VVT-i is a unique Toyota engine technology that is very mature. In recent years, most domestically produced Toyota vehicles, including new Vios, have been equipped with VVT-i. Similar to Honda VTEC principle, biggest feature of this system is that it can control intake camshaft according to engine condition and optimize valve timing by adjusting camshaft angle to get best valve timing. , so that intake camshaft can be controlled throughout increased torque in speed range, and can improve fuel economy, thus effectively improving vehicle performance.
9. Double VVT--i
(Dual Intelligent Valve Timing Engine) Dual VVT-i means separate engine intake and exhaust system control. During fast acceleration, VVT-i which controls intake increases intake time and increases valve lift, while VVT-i which controls exhaust delays exhaust time, effect is similar to a smaller turbocharger, can effectively increase engine power. At same time, by increasing volume of intake air, combustion of gasoline is more complete and goal of reducing emissions is achieved.
(Dual Variable Valve Timing, Variable Intake Engine) The base Rohens V-6 Lambda engine uses Time Dual Variable Valve Timing (D-CVVT) technology and features a new variable intake valve. system (VIS), which increases amount of intake air into cylinder, thereby improving fuel efficiency. It is equipped with a 3.8-liter V-6 engine with 290 horsepower, although power output is high, this does not affect its environmental protection and ultra-low emission control (ULEV) performance. Among them, Aisin's 6-speed overdrive automatic transmission is indispensable, with its smooth shifting and wide gear ratio, which provide Rohens' high power and excellent fuel efficiency.
(Turbo Direct Injection Supercharged Engine) TDI is abbreviation for Turbo Direct Injection in English, which stands for Turbo Direct Injection (Diesel Engine). In order to solve inherent disadvantages of SDI, a turbocharger device is installed on diesel engine, so that intake pressure is greatly increased, and compression ratio is generally higher than 10, so that large torque can be achieved at a very low speed, and through more complete combustion, amount of harmful particles in exhaust emissions are also significantly reduced. TDI technology allows fuel to be injected directly into cylinder through a high pressure injector. Equipped with Volkswagen Group's first direct injection turbocharged diesel (TDI), Bora TDI is very advanced and uses a number of advanced technologies such as pump injection system, variable vane turbocharger, etc. It is applied to domestic vehicles. Bora TDI uses latest high pressure fuel injection technology --- pump injection system. This system provides more complete mixing of diesel fuel with air and more thorough combustion; at same time, an oxidation catalytic reactor is used to greatly reduce CO emissions,HC and particulates, among which CO2 emissions can be reduced by 30% compared to gasoline vehicles of same displacement. In addition, use of EGR system significantly reduces formation of NOx, and its emission index complies with Euro-3 standard. The "TDI logo" of Volkswagen diesel engine is most successful diesel engine recognized in world.
(Diesel engine) The hydraulic timing device of distribution pump is driven by timing piston to move roller frame to adjust fuel injection timing. The high pressure cavity of timing piston communicates with pump chamber, pressure in pump chamber increases with speed, pressure in piston pressure chamber increases with speed, and pressure in piston pressure chamber increases with speed. advances timing of fuel injection. The Jetta electronic control system connects N108 electric valve in series between high and low pressure chambers of piston. The fill ratio adjusts pressure difference between high and low pressure chambers, and fuel injection timing changes. If fill ratio is large and pressure drop is small, synchronization is delayed, and synchronization controlled by a needle valve. The G80 lift sensor detects fuel injection timing and performs closed-loop control of fuel injection timing. The Volkswagen GDF-P diesel engine is more popular.
(Fuel Injection Engine) FSI is a new technology in field of gasoline engines, which stands for fuel stratification injection. Some are similar to high pressure oil technology in diesel engines. It is equipped with a demand-controlled fuel delivery system, then a piston pump provides necessary pressure, and finally a fuel injector injects fuel directly into combustion chamber at most appropriate time. Due to design of internal shape of combustion chamber, there will be a richer mixture around spark plug, while there will be a leaner mixture in other areas, ensuring that combustion is as lean as possible under conditions of smooth ignition, which is also stratified. The essence of combustion. Compared to an engine of same level, FSI's performance is significantly improved, but fuel consumption can be reduced by about 15%.
(Turbocharged stratified fuel injection engine) This extra T than FSI stands for turbocharger (turbocharger), and engine itself is indeed a turbocharger added to an FSI engine. Turbocharging is to use high temperature and high pressure of exhaust gases to make exhaust gas turbine rotate at high speed, which drives intake turbine to compress intake air.and increase air density.At same time, computer control to increase amount of fuel injection.Improve engine efficiency under same conditions. FAW-Volkswagen and Shanghai Volkswagen call their engines 1.4TFSI and 1.8TFSI, both of which are called 1.4TSI and 1.8TSI, name is extremely irresponsible. At same time, in order to avoid general objection to abbreviating TFSI as TSI, they explained: “Since we usually use three characters as name of engine-specific technology in normal system, so this time we will abbreviate TFSI as TSI. where T means turbo, SI means direct injection. The latest TSI engine of domestic models Magotan, Sagitar and others is actually not same as TSI mentioned above. The Magotan 1.8TSI and 1.4TSI engine that will power Sagitar effectively neutered supercharging and fuel stratification technology. Of course, this is also a consideration of issues of petroleum products and cost after localization. Because a supercharger kit costs at least 15,000 yuan and needs to be changed every 50,000 kilometers, while a more expensive turbocharger needs to be changed every more than 100,000 kilometers.
15 years, TSI
(Mechanical Turbocharger and Direct Injection Engine) The design of TSI (Tubular Injection Turbocharged Engine) is very ingenious. It actually integrates a turbocharger (Turbocharger) and a supercharger (Supercharger) together into an engine. The letter T in TSI does not mean a turbocharger, but a twincharger (dual supercharging). We mentioned above that a turbocharged engine has a dynamic neutral gear at both low and high speeds. To improve engine efficiency even more, add a supercharger and let it increase intake pressure at low speeds. The turbocharger can be sized larger to compensate for neutral power at high speeds to achieve superior power performance from low to high speeds.
16. Variable valve timing engine
Infinitely variable valve timing actuator for a Volkswagen engine comprising a valve equipped with a valve spring, a rocker arm that reciprocates valve, and a rotating cam that drives rocker arm. replace valve Cam with multiple working conditions of lift and opening and closing times, cam profile with multiple working conditions: one end is a low speed and light load cam profile, other end is high speed and heavy load cam profile, and a low speed cam profile and low load is same as profile of high speed and heavy load cam.move multi-state cam along its axial direction because profile of multi-state cam is continuous and smooth. to needs, and stepless valve phase adjustment can be realized. In addition, multi-operation cam profile covers various engine operating conditions, so utility model can well match engine's variable operating conditions. situation requires.
(Variable Lift System) AVS refers to variable valve lift system, also known as variable timing two-stage control system. Energy saving and power increase at same time. This technology is widely used in Audi vehicles.
(Variable Intake System) Under control of PCM, VAD airway can be opened at right time when engine produces more power (another airway is opened, which is equivalent to an increase in airway diameter), which can guarantee engine's maximum air volume. This technology is widely used in Mazda vehicles.
(Variable Intake Manifold System) on PC under M control, high torque is maintained from light load and low speed to heavy load and high speed. Working principle: change length of effective intake manifold to effectively control inertia of intake air flow in intake port, so that frequency of air flow pressure wave and frequency of intake valve coincide in time under different conditions. operating conditions, thereby guaranteeing engine air intake to maximum under any operating conditions. The bottom line is to use principle of medium-inertia harmonic boost to realize maximum air intake of engine. When engine speed is below 4400 rpm, VIS does not work, VIS valve is closed, and air flow path is longer; at an engine speed above 4400 rpm, VIS is running, VIS valve is open, and air flow path is shorter; In this way, it is possible to meet air volume requirement for different working conditions.
(Variable Swirl Control System) The intake manifold port opens differently at different water temperatures and speeds to meet air demand of engine under different operating conditions. Principle: Under same operating conditions, various orifices of VTCS valve change speed of air flow into engine, creating a vortex, which we often call a vortex, making engine's oil-gas mixture more complete. Especially in cold start engine at low temperature and low load, poor atomization of gas mixture, poor combustion and poor emissions The level reaches and exceeds Euro Ⅲ standard. Working process: under temperaturewater temperature is below about 62 degrees and engine speed is below 3750 rpm, area of the inlet pipe channel decreases, with a further increase in water temperature, speed increases even more, opening of VTCP valve is fully open, and tracheal area reaches its maximum.
(Electronic Throttle System) As name suggests, it does not control opening of intake manifold with a throttle cable, but uses a DC motor to automatically realize this through a reduction mechanism. Function and working process: It has main function of a conventional throttle valve, and its function is to open intake manifold port on main pipe and open various holes under different working conditions. Generally, car's throttle valve is driven by throttle pedal control cable. But this type of cable operated throttle has phenomenon of intake hysteresis under special working conditions such as fast acceleration, that is, under special working conditions such as fast acceleration, throttle opening signal was sent through throttle position sensor, but air, in fact entering cylinder does not keep up in time, and throttle is not very smooth due to disturbance of airflow, so air volume is unstable, and acceleration is not perfect and unstable. The electronic throttle valve can directly control DC motor to respond quickly according to throttle position signal, and open throttle valve in time to required opening, and electronic throttle valve will not be affected by airflow due to self-locking. self-braking action The disturbance oscillates to keep intake air volume and engine speed stable. Advantages: The response speed of electronic control method is fast, and it can ensure delivery in appropriate working condition in time. The air volume control accuracy is high, stability is good.
(Valve Timing System) We know that timing of intake valve opening and closing determines amount of air engine takes in. The intake air volume of a conventional car depends only on engine speed. The air intake quantity is fixed, that is, opening and closing time of intake valve is fixed, and air intake control of modern cars is designed to further improve performance of engine, it is more scientific to control opening and closing times of intake valve, to ensure that engine can reach maximum amount of intake air under various operating conditions to ensure best engine performance. Function: Automatically adjust intake valve opening and closing times via PCM in variousoperating conditions to ensure maximum engine consumption. Principle and working process: This is duty cycle signal sent by PCM. Under different engine running conditions, hydraulic control oil pressure control valve is opened to different opening degrees, and then intake camshaft is controlled to change various rotation angles, change opening and closing times intake valve and change intake air volume of engine. The throttle opening is logically controlled by PCM according to various signals according to a certain function, in order to achieve perfection of intake control.
23 years old, TSCV
(Swirl Control System) TSCV ensures stable combustion when engine is too cold or under low load by controlling swirl in combustion chamber. As a result, energy yield is improved and emissions are minimized.
24 years old, TKI
(Exhaust Turbocharging and Intercooling Technology) Chery 1.9D TCI diesel engine integrates several advanced engine technologies, and at same time has cleanliness and quietness of a gasoline engine, as well as economy and power of a diesel engine. These technologies include: TCI (Turbocharged Intercooler) technology, which maximizes engine power and torque without changing engine displacement; high pressure common rail direct injection technology, which directly drives intake camshaft to high pressure fuel pump, fuel injection is divided into three stages of pre-injection, main injection and post-injection to realize re-injection of fuel in combustion process, reduce temperature of combustion products in cylinder, reduce NOx, CO and PM formations are completely oxidized, and reduce formation of CO, PM, etc., to suppress formation of soot, EGR (exhaust gas recirculation) system reduces oxygen content of mixture in cylinder, thereby lowering combustion temperature, improving combustion process , and suppression of formation of NOx, a TVD (that is, a torsional vibration damper), a dual-mass flywheel and other designs are also used. The exhaust emissions of this engine can meet Euro IV standard, and fuel consumption has also reached advanced international level, which can be called a new generation of green energy.
(Vertical swirl lean combustion engine) BYD MVV's vertical swirl lean combustion engine is similar to general principle of in-cylinder direct injection engine.
(Variable Inertia Intake System Engine) Haima's VICS variable inertia intake system engine. Therefore, it has high torque characteristics over entire speed range, VICS systemcan provide high power and high torque throughout engine speed range from low to high rpm. This system is designed to control opening and closing of valve in air chamber according to torque requirements at different engine speeds, adjust length of intake manifold path, and improve efficiency of engine intake. After installing this system, engine can increase torque by at least 2.2% at low speeds.
(Natural Gas Engine) The exhaust gas purification converter of a natural gas engine usually consists of two parts: a honeycomb ceramic catalyst and a metal shell. temperature above 200~300°C, and convert harmful components CO, HC, NOX, etc. in exhaust gases into non-toxic water, carbon dioxide and nitrogen. The core of project is CNG engine exhaust gas cleaning technology, which belongs to three-component catalytic gas cleaning technology and is currently main method for cleaning exhaust gases of liquefied natural gas engines. At present, it is mainly used in taxis and some models.
(Variable Intake System, Intelligent Continuous Variable Valve Timing) Both NICS and C-VTC are Nissan technologies. NICS technology is that engine air filter is equipped with two intake pipes, and sensor can automatically open and close valve in main intake pipe according to engine speed, thereby improving intake efficiency, reducing intake noise at medium and low speeds. speeds and increased intake air at high speeds. This technology is similar to "variable intake manifold" commonly used in Audi A6 engines. The full name C-VTC - Continuous Variable Valve Tining Contorl (stepless variable valve timing) is an upgraded version of VTC, and this technology is similar to Honda's i-VTEC (upgraded version of VTEC). C-VTC controls optimum valve opening and closing timing via a clutch device mounted on front end of engine camshaft to improve combustion efficiency. C-VTC is a relatively advanced engine technology.
29, Ecotech DVVT
(Dual Variable Valve Timing Engine) VVT stands for Variable Valve Timing. We know that opening and closing of intake and exhaust valves in general engines is dependent on mechanical positive action. The timing mechanism opens and closes at appropriate crank angle position, which has nothing to do with engine speed and load. That is, time of opening and closing door corresponds to positioncrankshaft rotation, no matter high or low speed. Now pursuit of excellence in engine technology requires best performance under any load and speed condition. So someone has developed a mechanism that can change valve timing, which is realized through hydraulic or electronic control. DVVT and CVVT are both technologies, and DVVT refers to dual variable valve timing. Its valve timing has two torques that can be opened in position 1 or position 2, and can be adjusted based on speed and load. CVVT is stepless variable valve timing. It can be continuously adjusted between two limit phases in allowable valve timing. It must be said that it can provide better control, but it must have high control accuracy. VVT-i promoted by Toyota is owned by CVVT. The Ecotec DVVT is currently widely used in Buick series.
(Engine with intelligent two-valve intake control technology) EVIC-III intelligent two-valve intake control technology is used to reduce fuel consumption etc., as well as timely adjustment of valve timing, optimized fixed valve stack angle, engine power and output torque will be more linear, taking into account output power at high and low speeds, so that engine can run at high speed, it can reach maximum efficiency at low revs, reduce emissions and save fuel. (2) As an inertial variable intake system, by changing shape and length of intake manifold at low speeds, a long intake manifold is used to ensure air density and maintain power efficiency at low speeds, a short intake manifold is used at low speeds. high speeds for acceleration The speed at which air enters cylinder increases inertia of intake air flow and provides intake air volume at high speeds to accommodate engine performance at various speeds. After installing VIS, inertia of flow and suction efficiency of engine intake air flow are increased, thereby increasing torque and reducing fuel consumption. This technology is currently widely used in Roewe series.
(Variable Camshaft Variable Intake Manifold Engine) Lotus CamPro is an engine jointly developed by Proton and Lotus Engineering for high performance, low fuel consumption and low emissions. Thanks to this engine, Proton is officiallyo entered independent research and development market, and has world-class technology to produce next generation of motor, mainly to make motor breathe better, to improve CamPro's unique bottom torque loss problem, and improve fuel consumption figures in urban areas while driving, when upgrading ignition system to an independent ignition system to get more precise ignition control Increase low-rpm power to meet Euro IV standards, completely upgrade ECU, and apply variable camshaft and variable camshaft technology to engine intake manifold.
(Variable Displacement Engine) Chrysler's HEMI engine is equipped with an MDS system that can automatically switch between 4-cylinder and 8-cylinder modes. This technology is best suited for multi-cylinder engines and effectively reduces fuel consumption in traffic jams without affecting driver's desire to stimulate acceleration for large displacement vehicles. For example, after introduction of this technology, a conventional 8-cylinder engine is equivalent to installing two independent 4-cylinder engines, which can make one engine work and other rest according to driving needs.
33. Multistage Variable Intake Manifold Technology
Intake pipe length is computer controlled to provide high torque at low speed and high power at high speed.
(Integrated Motor) is produced in Italy, Brazil, Turkey and other countries with an annual production of millions of units. It is an economical engine with proven technology and consistent performance. It is widely used in various Fiat engines. on sedan. Take 188A4000 engine loaded in Fiat Palio as an example, engine displacement is 1242ml and compression ratio is 9.5±0.21. The engine control ECU is a Magneti Marelli® IAW 59F multi-point electronic injection system from Italian company Marelli. Using electrostatic ignition, sequential injection, non-return oil supply system and dual oxygen sensor technology, engine's emission level easily exceeds European No. 2 standard and improves vehicle safety. This system has following functions: fuel injection timing control, ignition timing control, electronic radiator fan control, idle speed control and management, cold start compensation control, self-diagnosis and self-learning, and emergency braking function.
(Variable displacement engine) will be installed in future Ford cars and trucks forto further improve vehicle's fuel efficiency. This engine technology is best suited for use with multi-cylinder engines. For example, for a 12-cylinder engine, after implementing this technology, it is equivalent to installing two independent 6-cylinder engines, with one engine running according to driving needs, while other is in an idle state. Thus, engine exhaust volume can be adjusted at any time, thereby reducing fuel consumption.
(Intelligent camshaft timing and lift control) MIVEC mechanism controls intake camshaft timing through ECU to issue precise instructions: engine ECU automatically searches for appropriate engine speed, intake air intake valve under various driving conditions. Optimal valve timing for air volume, throttle position and coolant temperature, and control hydraulic camshaft control valve, and determine actual camshaft timing through signals of various sensors, and then perform feedback control to compensate for system errors to achieve a better camshaft position can effectively improve power and performance vehicle, reduce fuel consumption and exhaust emissions. This technology is widely used in Mitsubishi vehicles.
37, Double VANOS Valvetronic
(Double Camshaft Variable Valve Timing) In 1992, BMW launched stepless variable valve timing control system, Double-VANOS Variable Valve Timing, which is world's first technology applied to BMW M3. The advantage of this control system is that intake and exhaust valve timing can be adjusted steplessly by precisely controlling camshaft angle according to engine's operating mode, and is not affected by accelerator pedal position and engine speed. In real driving, this means sufficient torque at lower engine speeds and optimal power at high engine speeds. In addition, Double-VANOS variable valve timing system with two camshafts can significantly reduce unburned residual gases, thereby improving engine idling performance. This technology is used in almost all BMW series.
(Multiple Fuel Injection Engine) The so-called MFI originally stands for Multiple Fuel Injection, which is itself a mature engine technology. The 2.0MFI engine is based on German AZM engine, combined with many factors such as Chinese roads, climate and fuel quality,and after careful retooling is a masterpiece.
(Intelligent Variable Valve Timing Control System) The technology of C-VTC Intelligent Variable Valve Timing Control System is basically same as that of VVT.
40, VVEL, TsVTKS
(Infinitely Variable Intake Height and Continuous Timing System) The Infiniti VVEL Infinitely Variable Intake Height system combined with CVTCS continuously variable intake timing also provides best kinetic energy and combustion efficiency. The unit optimizes efficiency with Continuously Variable Valve Lift (VVEL) technology to achieve a balance of power, response, fuel efficiency and emissions. Torque and power are increased by increasing power of combustion phase by constantly changing valve lift and thus amount of air in combustion chamber. Best of all, valves control intake stroke rather than traditional throttles, so throttle response is immediate and quick. VVEL technology improves fuel economy and reduces emissions compared to standard valve lift systems. Precise ECU transformation helps optimize engine power and torque. Gradual “expansion” that provides a “rolling wave” of acceleration rather than peak power.
(Variable Cylinder Management System) Honda Variable Cylinder Management System VCM technology, VCM system used in V6 i-VTEC engine is first application on Accord non-hybrid model, new generation VCM system can be used in three-cylinder, four-cylinder and full six-cylinder modes operation, whereas previously it was possible to switch only three-cylinder and four-cylinder operating modes. The VCM system allows new Accord to keep all six cylinders running in any situation requiring high power output, such as starting off, accelerating or climbing. However, when cruising at medium speed and light engine load, only one bank of cylinders is working, that is, three cylinders, and rear bank of cylinders stops working. Under moderate acceleration, high-speed cruising and driving on a gentle gradient, engine will use 4 cylinders to operate, i.e. left and middle cylinders of front group of cylinders work normally, and right and middle cylinders of rear group of cylinders work. usually. The all-new 3.5-liter V6 engine uses Honda's most advanced VCM technology with variable cylinder control. The VCM system can automatically switch between 3-cylinder, 4-cylinder, and all 6-cylinder operating modes. When vehicle starts, accelerates or liftsIt seems that all 6 cylinders are activated when high power output is required; Under engine load conditions, system works with only one bank of cylinders, i.e. with 3 cylinders; under medium acceleration, high speed driving and driving on gentle slopes, engine will use 4 cylinders to work, which significantly reduces fuel consumption. This 3.5-liter V6 engine is not only Honda's most powerful engine to date, but also reduces fuel consumption by 7% compared to previous generation Accord 3.0 model.
Fox Duratec-he inverted aluminum alloy motor is made of solid cast aluminum alloy, inverted design, maximum power can reach 104kw, maximum torque can reach 180Nm (2.0L engine), cooperating with vis ( variable inlet system) Variable inertia intake, plastic steel and other long intake manifolds, showing excellent level of fast acceleration power, smooth operation, high efficiency intake effect, low noise and low fuel consumption.
43 horizontally opposed engine
The engine pistons are evenly distributed on both sides of crankshaft and move left and right in a horizontal direction. The overall height of engine is reduced, length is shortened, center of gravity of vehicle is lowered, and vehicle runs more smoothly. The engine is installed on center line of vehicle, and torques generated by pistons on both sides cancel each other out, greatly reducing vehicle's vibration during driving, which is convenient. The speed of engine has been greatly improved and noise has been reduced.
(Lean Burn Technology) i-DSI is a dual spark plug ignition that can improve combustion efficiency. By increasing air-fuel ratio of mixture in engine, mixture is burned in a state in which air-fuel ratio is greater than value of theoretical air-fuel ratio. The relatively rare out-of-cylinder lean-burn technology is not as advanced as in-cylinder direct injection, but it costs less than direct injection engines.
(Direct Injection Gasoline Engine) Mitsubishi GDI engine reduces fuel consumption by 20-35% and carbon dioxide emissions by 20% due to lean burn technology, and power output is 10% higher than conventional engines with same operating volume. In-cylinder direct injection technology is an offshoot of lean burn technology. The biggest difference from conventional engines is its direct injection system. In fact, in-cylinder direct injection is not a new technology. Many diesel engines adopted this technology many years ago, and ingasoline engines, it was used only a few years ago. In-cylinder direct injection technology has two advantages: 1. The engine can directly inject gasoline into high-pressure combustion chamber before spark plug ignites, and at same time, under precise control of ECU, gas mixture is stratified. and burned down. This technology allows mixture near spark plug to be relatively rich and mixture away from spark plug to be relatively lean, thereby achieving lean ignition and stratified combustion more efficiently. 2. Since gasoline is injected directly into cylinder, compared with transmission's external injection, gas mixture does not need to pass through throttle valve, so air resistance generated by throttle valve to mixed gas can be reduced. .
(External injection engine) Fuel is injected into intake pipe. In order for gasoline to have time to mix with air after injection into intake pipe, fuel injector must be separated from valve by a certain distance. After gasoline and air are completely mixed in this space, it is introduced into cylinder for combustion. For this traditional design, if gasoline is injected directly into cylinder, it will inevitably lead to insufficient time for mixing air and gasoline. This unmixed gas obviously cannot meet ignition requirements of engine. The first thing a direct injection engine needs to solve is this problem.
(Direct injection engine) IDE still uses a lean mixture of air and fuel, but at same time increases exhaust gas circulation through EGR valve. EGR stands for Exhaust Gas Recirculation, which means Exhaust Gas Recirculation in Chinese. This technology reduces fuel consumption and effectively lowers combustion temperature - this is main reason for its effective solution to emission problem of GDI engines. As we all know, air is mainly composed of nitrogen, oxygen, carbon dioxide and some other inert gases. Among them, nitrogen, constituting largest proportion, is a very stable gas, and it is generally difficult to oxidize directly with oxygen. However, at high temperature and high pressure, nitrogen, which is usually very stable, can easily react with oxygen to form very harmful oxides of nitrogen. Conventional engines, including above-mentioned GDI engine, when they are running normally, working environment in cylinder is just in a state of high temperature and high pressure, so that mixture of air and fuel easily generates nitrogen oxides after combustion. . This is especially problematic for engines with direct injection into cylinder. Since compression ratio of direct injection engines is usually designed relatively high, cylinder pressure is higher thanbull engines, which facilitates formation of nitrogen oxides. We all know that nitrogen oxide emissions from diesel engines are usually much higher than from gasoline engines, mainly due to high compression ratio of diesel engines. In case where pressure cannot be reduced (because a high compression ratio is a necessary means of improving engine efficiency), only way to reduce emission of nitrogen oxides is to lower combustion temperature in cylinder. The IDE engine's EGR system is designed to reduce combustion chamber temperature by reintroducing some of exhaust gases ejected from cylinder into intake pipe to mix with fresh air and fuel for combustion. We know that exhaust gases after combustion cannot be burned again. After exhaust gases are introduced into cylinder, they will occupy part of usable volume in cylinder. This effect is equivalent to reducing engine displacement, which can effectively reduce combustion temperature naturally while naturally reducing exhaust emissions.
(Variable Intake Valve Timing Engine) i-VCT, also known as Intake Variable Timing System, can use engine to deliver more than 90% torque between 2000 and 5000 rpm, keeping engine running smoothly . . VVT-i, Variable Valve Timing System, emphasizes low speed performance, but in reality Toyota's VVT-i doesn't have much torque below 2000 rpm and it feels like there's more torque at low speeds. revolutions. speeds and high gears. This is because VVT-i operation cannot cover low speed range, it can only rely on gear matching. However, Toyota gears place too much emphasis on smooth driving, resulting in a lack of passion for driving an integrated car. But dynamics in acceleration phase is good, which is also specially tailored to features of city driving. The inline four-cylinder, 16-valve, aluminum alloy DURATEC-HE2.3 engine with two overhead camshafts, installed in new third generation Ford Mondeo, uses advanced technologies such as i-VCT variable valve timing, and its emissions comply with Euro IV standards. . Compared with products of same level, it is more economical at low speeds and has higher power output at high speeds.
(Intelligent Direct Injection Engine) The Cadillac SIDI engine combines Intelligent In-Cylinder Direct Injection, D-VVT Electronic Dual Valve Timing and latest ECM. The design of SIDI dual-mode direct injection engine has been significantlychanged. Compared with original intake manifold injection method, S engine in IDI engine, multi-port fuel injection system is replaced by a variable valve in-cylinder direct injection system, which is to implant fuel injector into cylinder, spray fuel into cylinder at high pressure, and mix it with ignition air to understand that in-cylinder lean combustion improves engine efficiency. It also has excellent fuel economy and low exhaust emissions. In addition, since direct injection technology provides a higher compression ratio (SIDI compression ratio reaches 11.1:1), it can significantly reduce cylinder knock and reduce engine vibration. The above benefits can significantly increase engine life compared to conventional EFI engines. Based on above characteristics, SIDI dual-mode direct injection engine can increase maximum power by about 15% and maximum torque by about 8% compared to multi-point fuel injection engine of same displacement and at same time have a fuel saving efficiency of more than by 3%.
(Intelligent Valve Timing and Intelligent Electronic Throttle Control) The Lexus SC430 is equipped with a 4.3-liter 32-valve V8 engine equipped with intelligent variable valve timing (VVT-i) and intelligent electronic throttle. control system (ETCS-i) has a constant power flow. The most admired in world is special design of cabriolet body.
51 Twin Turbo Engine
Mercedes-Benz twin turbocharging is one of turbocharging methods. For exhaust gas turbo hysteresis phenomenon, two turbines, one large and one small, are connected in series or two identical turbines are connected in parallel. turbo lag effect. Conventional turbocharging is single turbocharging, divided into mechanical turbocharging, exhaust gas turbocharging, and compound turbocharging. Mechanical boost is that engine directly drives turbine. The advantage is that there is no turbohysteresis. The disadvantage is that some power is wasted and boost value is low. Exhaust turbocharging uses remaining kinetic energy of engine exhaust gases to rotate turbine. The advantage is that high speed of turbine and large boost value can greatly increase power. (Below 1800 rpm) kinetic energy of exhaust gases is small and it cannot turbocharger spin at high speedsti to increase intake pressure. At this time, engine power is equivalent to natural suction power. When speed increases, turbocharger works and power suddenly increases. Series and Parallel Connection of Twin Turbine Superchargers On a twin turbo car, you will see two groups of turbines connected in series or in parallel. Parallel connection means that each turbine group is responsible for half of engine's cylinders, and each turbine group is of same specification, such as Porsche 911 turbo, Skyline GT-R RB26DETT, Supra 2JZ-GTE and new BMW 3.0. all twin turbines connected in parallel An outstanding representative of turbocharging, its advantage is that boost response is fast and pipeline complexity is reduced. A tandem turbine usually consists of a large and a small group of turbines connected in series. At low speed, a fast response small turbine is driven, so that torque at low speed is sufficient. At high speed, large turbine intervenes. to ensure sufficient air intake and increase power output. The 13B-REW RX-7 engine is a good example of a stock turbo. Conventional turbocharging is single turbocharging, divided into mechanical turbocharging, exhaust gas turbocharging, and compound turbocharging.
52 years old, VIM
(Variable intake and exhaust manifold engine) Lamborghini Lamborghini VIM variable intake and exhaust manifold engine Since mid-1990s, variable intake manifold technology has become increasingly popular in vehicles. This technology can improve engine torque output at low and medium speeds and does not adversely affect fuel economy and power at high speeds, thereby improving engine adaptability.
The conventional fixed intake manifold can only be designed according to specific requirements of engine, or according to requirements of high speed and low speed, or a compromise method, but no matter which design, everything can not be taken into account needs of different speeds . Variable intake manifold technology can be split into two or more stages to adapt to different engine speeds.
Variable intake manifold technology is somewhat similar to variable valve timing technology, but variable intake manifold technology pays more attention to increasing torque output at low speeds (the effect of increasing output power at high speeds is not obvious)) so this technology is widely used in ordinary civilian vehicles. However, this is not absolute. Since this technology can provide better engine response, this technology has gradually been applied to sports cars such as Ferrari 360 and 575. Compared to technologyvariable valve timing variable intake manifold technology has a lower cost - it only needs a few simple solenoid valves and intake pipe shape design; while variable valve timing technology requires complex and precise control. hydraulic system, and when changing valve stroke, some special camshafts are required.
There are currently two Variable Intake Manifold technologies: Variable Intake Manifold Length and Variable Intake Resonance, both of which are realized through intake manifold geometry. We will discuss these two techniques separately below. Variable length intake manifold Variable length intake manifold is a technology widely used in general civil vehicles. The length of intake manifold is mainly for adjustment in two sections: a long intake manifold is used at high rpm, a short intake manifold is used at high rpm. . Why is intake manifold short at high rpm? Since this can make intake air smoother, it should be easy to understand, but why would you need a long intake manifold at low speeds, wouldn't that increase intake resistance? Because engine air intake frequency is low at low engine speeds, long intake manifold can collect more air, so it is very suitable to meet intake requirements of engine at low speeds, thus improving output torque. In addition, a long intake manifold can also reduce airflow rate, which can improve air-fuel mixture, more complete combustion, and can also increase output torque. To better adapt to intake requirements at different speeds, some systems use a three-stage variable length intake manifold design, such as V8 engine. Each bank of cylinders has an intake manifold adjustable in three sections for a total of 24 intake manifolds. Audi didn't actually separate intake manifold, but placed a curved intake manifold around a central rotor, and rotor rotated to different positions to give different length intake manifolds. The whole system is placed inside V-shaped corner of V-shaped engine. Lamborghini also has a more upscale Reventon with a three-stage variable geometry intake manifold and an engine with variable intake and exhaust camshaft technology.
53. Petrol-electric hybrid system
The so-called hybrid power usually refers to hybrid power of gasoline and electricity, that is, mixture of fuel (gasoline, diesel, etc.) and electricity. A hybrid vehicle is a vehicle that has an electric motor as engine's auxiliary power. Hybrid cars have high performancefuel economy and excellent driving performance. Hybrid vehicles use fuel, and when starting and accelerating with help of electric motors, fuel consumption can be reduced. Fuel costs are lower compared to cars. In addition, electric motor that assists engine can generate powerful power at moment of starting, so owner can enjoy stronger starting and acceleration. At same time, a high level of fuel economy can be achieved.
Currently, there are three main types of hybrid vehicles: one of them is "parallel mode" in which engine is main power and electric motor is auxiliary power. (Parallel hybrid) This method is mainly driven by engine. It uses an electric motor to generate a lot of power when it restarts. Engine fuel consumption. The structure of this method is relatively simple and only electric motors and batteries need to be added to car. The other is "series-parallel mode" in which only electric motors are used to drive at low speeds, and motor and electric motors are driven together as speed increases. (Fuel Cell) It is powered only by electric motor at start-up and at low speeds. As speed increases, motor and electric motor distribute power efficiently. This method requires power distribution devices and generators, so structure becomes more complex.
There is also a "tandem mode" of electric vehicles driven only by electric motors. (Hybrid Series) The engine is only used as a power source, and vehicle is only driven by an electric motor. The drive system is only an electric motor, but since it also requires installation of a fuel engine, it is also a type of hybrid vehicle.