Looking forward to the development of global automobiles, the small displacement of has become a trend which is currently being pursued by major automobile manufacturers. The reason is that global warming has continued to increase, making people begin to realize the importance of protecting the environment. With smaller emissions and stricter emission standards, many countries, including China, have stricter vehicle exhaust emissions. Demanding requirements. However, as the displacement becomes smaller, many consumers are beginning to worry whether 1.5T power is sufficient? Will it affect driving quality? How far has the 1.5T engine been developed at this stage? On June 21, 2020, the first model of Changan Automobile's high-end series, UNI-T, was officially launched. It is equipped with Changan Blue Whale NE 1.5T high-pressure direct injection engine.
As a world-renowned automobile manufacturer, Volkswagen has also launched a new generation of 1.5T turbocharged engine code-named EA211 EVO, and models equipped with this engine have been launched in Europe. After being introduced into China, it is expected that the eighth-generation Golf and other models that will be launched in the second half of 2020 will also use this engine.
Today, I am curious to have an in-depth analysis of these two 1.5T engines.
1. 1.5T, is the power really enough?
This is probably the question that many consumers ask the most when they see a car equipped with a 1.5T engine. The full name of T is Turbocharger, which means . 1.5T refers to the turbocharging technology developed for a 1.5-liter engine. The turbocharger device can change the intake air volume of the engine, so that the fuel vapor is burned more fully in the cylinder, thereby increasing the output power of the engine. In the inertial thinking of many people, the larger the number in front of T, the larger the displacement and the higher the power output. In fact, this is not accurate.
Volkswagen EA211 EVO new generation 1.5T turbocharged engine. With the continuous improvement of engine technology, 1.5T has become more and more mature, and the power output is also rising. For example, the Volkswagen EA211 EVO new generation 1.5T turbocharged engine is divided into high and low power versions. The low-power version has a maximum power of 96kW (130 hp) and a maximum torque of 200N·m; the high-power version has a maximum power of 110kW (150 hp) and a maximum torque of 250N·m (data source is the European version). The maximum power of 110kW is very close to the power of some 2.0T engines. The performance of Changan’s Blue Whale NE1.5T high-pressure direct-injection engine is even further. has a maximum power of 132kW (180 horsepower) and a maximum torque of 300N·m. This data performance has even exceeded some 2.0T engines. .
Blue Whale NE 1.5T high-pressure direct injection engine Overall, the power of the 1.5T engine is improving, but there are big differences in the performance of power parameters of various brands. Compared with the 1.5T low-power version of the Volkswagen EA211 EVO, the maximum power and maximum torque of Changan Blue Whale NE 1.5T is 37.5% higher and the maximum torque is 50% higher. is even higher than that of the Volkswagen 1.5T high-power version. The maximum power is also 20% higher than . More in line with domestic consumers' demand for power.
2. Why is 1.5T engine so powerful?
Whether it is a new generation of Volkswagen EA211 1.5T or Changan Blue Whale NE 1.5T, the power parameters are already very powerful, especially the Changan Blue Whale NE 1.5T engine, and the power data has even surpassed some 2.0T engines. As the first modular engine R&D platform of a Chinese brand, the "Blue Whale NE Power Platform" not only uses many industry-leading engine technologies, but also has strong forward-looking and compatibility.
1, Stroke & Displacement
The volume of space through which the piston moves from top dead center to bottom dead center is called cylinder displacement. If the engine has several cylinders, the sum of the working volumes of all cylinders is called engine displacement. Engine displacement is one of the most important structural parameters. It is more representative of the size of the engine than the cylinder diameter and the number of cylinders. Many indexes of the engine are closely related to the displacement. usually has a large displacement, and the greater the energy released per unit time (that is, the conversion of the chemical energy of the fuel into mechanical energy), the better the "power".
As Volkswagen Group's most important future small-displacement supercharged engine, EA211 EVO engine adopts many advanced technologies. In terms of structure, although the overall engine still adopts an inline four-cylinder layout, and the cylinder spacing and bore are consistent with the 1.4T engine, , but the stroke has been increased from 80mm to 85.9mm, and the engine displacement has therefore been increased from the original 1395ml to 1498ml . Changan Blue Whale NE1.5T high-pressure direct injection engine has a displacement of 1494ml, which is basically at the same level as Volkswagen's EA211 EVO engine. While maximizing the engine's power performance, it is also closer to the needs of Chinese consumers. engine can reach the peak torque at 1250 revolutions. In the low speed driving state in the urban area, the engine can reach the peak torque faster. In high-speed driving, the peak torque of 300N·m can also have good power performance, which meets the user's demand for stronger power.
2, combustion system
As we all know, the current mainstream automobile engines generally adopt four-stroke cycle technology , which means suction, compression, Expansion does work and exhausts.
1. The piston moves downward so that the mixture of fuel and air enters the cylinder through one or more valves;
2, the piston moves upwards to compress the mixed gas;
3, and then near the compression stroke At the apex, the mixed gas is ignited by the spark plug, and the thrust generated by the combustion air explosion forces the piston to move downward to complete the work stroke;
4, finally the burned gas is discharged out of the cylinder through the exhaust valve.
The most representative four-stroke engine is Atkinson cycle, Miller cycle, Otto cycle , such as Volkswagen's low-power version of EA211 EVO 1.5T engine, which uses It is Miller cycle + integrated exhaust with single outlet cylinder head, is good for fuel consumption, but it affects power . The high-power version uses Otto cycle + single outlet cylinder head integrated exhaust.
Blue Whale NE 1.5T engine adopts Otto cycle + dual outlet cylinder head integrated exhaust . "Dual inlet and dual outlet" (double outlet cylinder head integrated exhaust, dual scroll electronic control supercharge), good power, fast response, short warm-up time, low fuel consumption, and better user experience. With the dual-outlet structure, the exhaust of each cylinder interferes with each other, which is more conducive to combustion and makes the exhaust pulse effect into the turbine stronger.
General dual-exit cylinder head integrated exhaust is only used in luxury cars and large-displacement cars, such as Volkswagen and Audi’s EA888 series engines (used in Audi’s 2.0L displacement A3, A4L, Volkswagen Passat 2.0L displacement, Tiguan), Toyota Crown 2.0T.
3, supercharger
The larger the air intake of the automobile engine, the more sufficient combustion and the greater the output power of the engine. However, due to technical reasons such as volume, the size of each engine block is limited, that is to say, the amount of air intake is also limited. At this time, if you want to get more power output, you need to use a turbocharger.
turbocharger is actually a air compressor , which increases the pressure and density of the air by compressing the air, thereby increasing the fuel quantity and adjusting the engine speed, and finally increasing the engine outputOutput power.
Volkswagen low-power version of the EA211 EVO engine is equipped with VTG variable section turbo technology . The angle of the turbocharger blades is adjusted through the electronic control system, thereby adjusting the turbocharger tube The diameter of the turbine increases the response speed of the turbine by 35%, and the maximum torque of 200N·m can be output from 1400 rpm, which makes up for the lack of low torque in the Miller cycle. The high-power version is not equipped.
Volkswagen EA211 EVO 1.5T VTG variable area turbocharger Blue Whale NE 1.5T engine adopts twin scroll electromagnetic control turbocharger . The dual-scroll tube, or dual-channel supercharger, can make better use of exhaust pulse energy, improve low-speed torque and transient response, and achieve a similar effect to the use of VTG variable-section turbine technology, thereby effectively improving users' common driving conditions The dynamic performance of the entire vehicle under the drive improves driving pleasure.
At the same time, the boost torque reaches 200Nm/L. The larger the boost torque, the stronger the engine power. The Ferrari 488 Pista has achieved 197Nm/L, and Blue Whale NE power Achieved 200Nm/L, so that family cars can also have power output comparable to luxury sports cars.
In addition to these, there are many factors affecting engine power, such as in-cylinder direct injection technology (the technology that directly injects fuel into the cylinder and mixes the intake air). Blue Whale NE 1.5T engine and Volkswagen high and low power version EA211 EVO engine both use 350bar ultra-high pressure direct injection technology. This technology can make fuel particles as small as 8 microns in diameter, which is only one-fifth of the diameter of ordinary human hair. The smaller the fuel particles, the better the mixing with the air, and the more complete the combustion.
Third, the power level of independent brands can also lead the world
Once upon a time, when it comes to car engines, only foreign brands have been sold, but in recent years, with the upgrade of made in China and China With the rise of creation , domestic brands are no longer controlled by others on the engine, and even have the momentum to catch up and surpass.
The new generation 1.5T turbocharged engine of Volkswagen EA211 EVO, the low-power version has a maximum power of 96kW (130 hp) and a maximum torque of 200N·m; the high-power version has a maximum power of 110kW (150 hp) and a maximum torque of 250N·m . But compared with the current 1.4T engine, the performance has not been improved. This is because the purpose of the research and development of the new generation of 1.5T engines is not to improve performance, but to reduce fuel consumption.
Compared with the fuel consumption chart of the engine's universal characteristics, the Volkswagen EA211 1.5T EVO can reduce the fuel consumption by up to 30% compared to the Volkswagen 1.4T in some areas of medium and small loads, and can also reduce 10%~15 in other areas. % Of fuel consumption.
Volkswagen did this because various countries have more stringent standards for vehicle emissions. China will implement the fifth phase of fuel consumption regulations in 2020, and will implement the RDE actual road driving emission regulations in the national 6b regulations in 2023. Europe also has corresponding Euro 6 emission standards. Volkswagen does not improve power performance but focuses on reducing fuel consumption in order to cope with the new emission standards.
As everyone knows, generally speaking, the improvement of power performance and the reduction of fuel consumption are incompatible. The stronger the power, the greater the fuel consumption. Therefore, in order to meet the national 6b lower emission requirements, many car companies have I chose not to increase power, or even reduce power. But this is not very friendly to consumers. After all, everyone wants their car to be as powerful as possible.
Blue Whale NE1.5T was considered to meet the national 6b standard at the beginning of its development, but it did not sacrifice its power level for this. The maximum power of Blue Whale NE1.5T engine reaches 132kW, the maximum torque reaches 300N·m, and it adopts individually controllable PCJ. At present, only Changan in the Chinese market has this technology, which can individually control the cooling of the piston, and use full MAP to control the cooling of the piston under cold start or low-to-medium load conditions, reducing the power consumption of the oil pump at low and medium load , Reduce carbon deposits, reduce friction, so as to achieve the effect of fuel saving. In other words, the blue whale NE1.5T engine not only improves the power, but also takes into account the fuel consumption and meets the national 6b. This is not something that any car company can do. Winning technology is the sustainability of domestic brands. The right way of development. Hopefully, in a few years, we can see "China Chip" spread all over the world, and Chinese car companies will go global.
