Why can Teana achieve the compression ratio of 14, while Mazda achieves 13, but it can't be blown everywhere? -
In essence, in order to achieve high compression ratio, Nissan and Mazda adopt different ways, but their purpose is to optimize the actual compression ratio of the engine through optimization and adjustment, improve combustion efficiency, and thus reduce fuel consumption.
Let's talk about Mazda's creation of Blue Sky and Nissan's two realization methods, as well as their respective advantages and disadvantages:
Strictly speaking, the physical compression ratio of Mazda Chuangchi Blue Sky Engine is not only 13: 1. Originally, the physical compression ratio of Japanese engine reached 14: 1, but it was reduced to 13: 1 in order to adapt to domestic engine oil. Theoretically, the engine compression ratio varies from
But after increasing the physical compression ratio of the engine, the biggest problem that needs to be solved is engine knocking. Because the pressure is too high and the temperature is too high, 92/95# gasoline can't adapt to it, which leads to knocking. In order to avoid knocking, Mazda adopted various technologies to control it:
In fact, it is to control the crown change of camshaft at different speeds, realize the delayed closing technology of intake valve, realize Miller cycle, that is, "spit back when you are full", thus reducing the actual pressure in the cylinder, achieving the expansion ratio greater than the compression ratio, and finally controlling the actual pressure in the cylinder.
In order to further reduce the in-cylinder temperature and suppress knocking, Mazda engineers also adopted ultra-high pressure fuel injection control, which made the fuel atomization more thorough, the combustion time shorter and the atomization time shorter. In addition, a special concave hole is specially designed at the top of the piston to optimize the air flow and increase the tumble ratio, thus improving the flow efficiency of mixed gas and reducing the in-cylinder temperature.
In order to avoid exhaust gas backflow after combustion of ordinary engines and reduce exhaust gas cross-winding, Mazda specially developed 4: 2: 1 extended exhaust technology, which can improve exhaust back pressure and reduce exhaust residue.
In order to further increase the combustion efficiency, Mazda has carried out lightweight design for all parts of the engine. For example, using roller follower can reduce the throttle friction by more than 50%, using electronically controlled variable oil pressure small oil pump can reduce the pumping loss by about 45%, connecting rod, main journal, crankshaft, piston and piston pin are lightweight, and low tension piston ring is adopted to reduce the friction loss. The adoption of these technologies makes Mazda Chuangchi Blue Sky Engine a real reality.
In order to realize high compression ratio technology, Nissan has taken a completely different path. However, this road is really difficult. Nissan has developed for 20 years from project establishment to mass production.
From the point of view of engine compression ratio and combustion efficiency, simply increasing compression ratio can certainly improve fuel economy and reduce emissions, but the dynamic performance of the engine is not good in the low speed range. Therefore, it is ideal to have an engine with high compression ratio, which can achieve high thermal efficiency under medium and low loads, low compression ratio under high loads, and increase the limit torque through turbocharging. This is the original intention of Nissan to develop VC-TURBO variable compression ratio for many years.
Nissan's solution is to add an eccentric connecting rod mechanism between the piston connecting rod and the crankshaft, and adjust the movement height of the piston and the connecting rod through the electronic control motor, so that the compression ratio will be changed from 8: 1 to 14: 1 at a specific speed, so as to realize low speed, low compression ratio, high speed and high compression ratio. The 2.0T turbocharged engine can output a maximum power of 200kW and a peak torque of 400 Nm.
Of course, as a product that grinds a sword every day for 20 years, VC-TURBO engine is armed with technology to the teeth:
Mazda's technology is generally only applied to naturally aspirated engines in China, and foreign turbocharging products have been developed. Theoretically, the variable compression ratio technology that Nissan can use and produce can be applied to self-priming and turbocharged engines.
Mazda's technical structure is relatively simple, and the life of naturally aspirated engine is relatively longer, while Nissan's VC-TURBO will theoretically bring greater instability, more friction and shorter life because of its more complicated mechanical connecting rod.
Nissan's turbocharging is indeed better, and the variable compression ratio can provide better power and fuel consumption performance in both low and high speed ranges. On the one hand, Mazda's blue sky can only be used for natural inhalation, on the other hand, the fixed compression ratio is not as flexible as the variable compression ratio.
Nissan's VC-TURBO has more complicated mechanical structure and higher cost. Mazda's Chuangchi Blue Sky engine is relatively low. However, Chuangchi Blue Sky is not Mazda's latest technology. Mazda's SKYACTIV-X compression ignition engine pioneered the high compression ratio of gasoline engines. Limited to space, I won't go into details today. If you believe in football, you can leave a message in the message area.
Mazda's models sold all over the world are the first generation Chuangchi Blue Sky Engine, and the compression ratio of this engine is 14: 1. However, when it was introduced into Chinese mainland market, the compression ratio was slightly adjusted to 13: 1, probably to adapt to the domestic gasoline quality.
Therefore, the compression ratio of Chuangchi Blue Sky Engine in Chinese mainland market is slightly different from that in overseas markets. In addition, Chuangchi Blue Sky Technology has no other difference, and all of them are sold simultaneously. Of course, the vehicle configuration is different. For example, Angkor Saila, the overseas market started at 2.0L, and the domestic market started at 1.5L, mainly because the joint venture factory controlled the cost and reached the price suitable for the domestic consumption level.
The price of a horse and a horse is cheaper than that of Mazida in overseas markets, but even so, the price of Mazda is still on the high side among domestic models of the same class, which is one of the reasons for Mazda's low sales.
Mazda's second-generation Chuangchi Blue Sky Engine has achieved the compression ratio of 18: 1, and has been put on the market in mass production. The fuel consumption of this engine is lower than that of the previous generation, which is a very difficult progress in internal combustion engine technology. It can be said that the compression ratio has reached the limit. However, apart from a slight decrease in fuel consumption, there is no huge breakthrough in power, but the price is gratifying. The price of Angkeira equipped with a 2.0L high compression ratio engine in Changan Mazda has reached 199800 yuan, which completely loses its cost performance, and it is destined to become a product that is not popular, and its sales volume is basically impossible to talk about.
The subject unilaterally characterized Mazda's engine as "bragging", which may be due to the lack of more understanding of Mazda. Mazda is a maverick niche brand, which can't be compared with selling cars, but it has always been persistent in studying automobile technology, such as Chuangchi Blue Sky System, which is not simply understood as engine technology. Chuangchi Blue Sky is a complete vehicle system, which complements vehicle technology and training as much as possible, which means Mazda has made a lot of efforts in places you can't see.
Because of its stubbornness and personality, it has won quite a lot of praise and has a large number of fans all over the world. The global annual sales volume is more than10 million, which should be passable for a small car company like Mazda.
Mazda's car has many distinctive features, which may only be realized by people who have driven it. This is the reason why its sales volume is not large, but the topic is constant. It is not bad to say that it is "blowing" because it does have something worth "blowing".
Daily variable compression ratio, the specific time is only 14: 1, while Mazda's full working condition is 13: 1.
To answer your question with the words of many car critics, Teana's variable compression ratio engine is not comparable to other pure fuel engines, because it is a dimension reduction blow, and Nissan is one latitude ahead.
The Japanese bought Honda, Mazda and Toyota, but never considered Nissan's cars, so the safety is rubbish, let alone controlled. There is nothing but sofa space.
Mazda's compression ratio is much stronger than Nissan's, and it is reduced to thirteen to adapt to domestic gasoline, which reduces the demand for oil products. In other words, Mazda can add more than 92% oil, and Teana uses a compression ratio of 14, but it must add more than 95% oil.
No matter Teana or Mazda, they are playing the edge ball of concept. This compression ratio is not specific. Whether it is 13 or 14, it is actually the expansion ratio. See double cycle for details.
Chuangchi Blue Sky II compression ratio 18: 1 So I asked you if your face hurts?
Foreign 14, domestic 13. Domestic oil products are different.
In addition, Honda's reduction in distribution is also in line with Mazda's proportion? It takes too long to buy Honda?
In the bombed Civic, the B-pillar was broken and the bumper was covered with iron.
Angkor Sela 1800 MPa bumper
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