With the advent of the new energy era, fuel consumption no longer seems to be the pain point of current car users, the era of "high power and high fuel consumption" is gone, plug-in hybrid models have become the mainstream, gradually replacing the market position of some pure fuel vehicles, but because plug-in hybrid still needs internal combustion engines, for high-wind resistance off-road vehicles, users are still concerned about fuel consumption performance, so what determines fuel consumption?Is the test really accurate?How do I measure real fuel consumption data?Let's break it down in detail.
The difference between fuel consumption and real fuel consumption of the Ministry of Industry and Information Technology
The Ministry of Industry and Information Technology has a set of standard measurement methods for fuel consumption, some models will be calibrated with NEDC, and some models use WLTP or WLTC, in which NEDC is the data measured by the vehicle on the horsepower machine, due to the absence of wind resistance, etc., the value is significantly different from the real driving environment, the difference between some models is more than 20%, and WLTP simulates more driving scenarios, including at least 12 driving scenarios, including braking, acceleration, gear shifting, and various road conditions during the test, and the test mileage is 23.25 km, the fuel consumption of the Ministry of Industry and Information Technology is about 1 million kilometers different from the real fuel consumption5-2L, that is, the fuel consumption of the Ministry of Industry and Information Technology plus 15-2, and normal driving fuel consumption is close.
There are several factors that affect fuel consumption
Driving in low gear and high speed:In order to reduce the speed of the internal combustion engine at high speed, most of today's fuel vehicles are more than 7 gears, Ford and GM have 10-speed gearboxes, and plug-in hybrid models also have 3 gears, the speed of the engine directly affects fuel consumption, generally speaking, automatic transmission models are automatically upshifting within 3000 rpm, but after turning on the sports mode, the gearbox is delayed in upshifting, at this time the vehicle completely exerts the power of the internal combustion engine, accelerates rapidly, but fuel consumption rises.
High-speed wind resistance:We all know that the fuel consumption of the vehicle will be reduced when driving on the highway, but this high speed only represents the speed limit, such as 120km h cruise, the vehicle is in 7th gear, at this time the engine speed is only 2000 rpm, lower than the urban fuel consumption, but if to the ultra-high speed, such as the recent ** Yao will BYD Formula Leopard 5 to 180km h, test fuel consumption, at this time the vehicle is not only high, but also to face huge wind resistance.
Specifically, aerodynamic drag is proportional to the square of the velocity, so the power required to overcome the drag is proportional to the cube of the velocity. To put it simply, fuel consumption increases sharply with the rise of speed, if you combine urban areas and high speeds, the average speed can not be too fast, like the fuel consumption of the Ministry of Industry and Information Technology, the average speed is below 50km h, taking the WLTP test as an example, the average speed of the entire test process is only 465km/h。In the Equation Leopard 5 test, according to the relevant information, the vehicle had 3 periods of more than 180km h and 6 periods of more than 170km h.
There is an extreme example of how speed affects fuel consumption, and that is the Bugatti CHIRON Super Sport testWLTP fuel consumption per 100 km is 2147L, after filling up the 100L fuel tank, the normal driving range is more than 400 kilometers, and after the speed breaks through 400km h, the 100L fuel tank can be emptied after 9 minutes, and the conversion range is only about 60 kilometers, which is enough to see the impact of speed on fuel consumption.
Frequent braking:Urban stop-and-go, fuel consumption will be significantly higher than the uniform speed section, in addition to idle fuel consumption, braking and re-acceleration also affect fuel consumption, braking means the disappearance of kinetic energy, re-acceleration requires more power to tow the vehicle, in the first test of the Leopard 5, there is an abnormal sudden braking and rapid acceleration phenomenon.
Temperature:Fuel consumption is higher when driving a vehicle in winter because the air becomes denser as the ambient air temperature drops, which increases air resistance. For every 5 degrees Celsius drop in temperature, air resistance increases by 2%, at which point fuel economy decreases by about 1%. Therefore, for example, the WLTP test will set the temperature at 20 degrees to prevent the change in fuel consumption caused by the temperature difference.
How to test accurate fuel consumption
If you want to test your daily driving fuel consumption, choose a car detective to share our method of testing fuel consumption, you can go to a nearby gas station to fill up the fuel, add until you can see the fuel from the fuel tank mouth, and then clear the segmented mileage in the car, and then drive normally (a variety of road conditions, multiple periods) 100 kilometers or 50 kilometers, and then go to the same gas station with the same fuel gun to fill up the fuel tank, the fuel tank mouth can see the oil, the amount of refueling divided by the mileage, calculated a more accurate fuel consumption.
Car Pick Detective Viewpoint:Due to everyone's different driving methods, different driving environments, fuel consumption data is only used as a reference, not an accurate value, we have listed several factors that affect fuel consumption, usually driving to avoid these, you can reduce fuel consumption, what other factors do you know that affect fuel consumption?Welcome to discuss.