A diesel engine TDI-equipped vehicle will be added to the new Volkswagen Golf, which was introduced in Japan in June of this year. It will be on sale from January 7, 2022. It will be available in 4 grades, and the price will be 30,266.04 to 35,925.55 usd.
Exterior of Volkswagen Golf
The TDI R-Line uses a dedicated exterior, and the shooting vehicle is equipped with 18-inch aluminum wheels (tire size: 225 / 40R18) that are available as an option for the TDI R-Line.
　This TDI is an evolved version of the 2.0TDI EA288 engine that the predecessor was equipped with, and the name will be EA288evo. The compression ratio is from 16.2 to 16.0. The maximum output is the same as 110kW (150PS), but the generated rotation is 3000-4200rpm (the predecessor was 3500-4000rpm). The maximum torque will also be increased by 20Nm to 360Nm (36.7kgfm) / 1600-2750rpm (the predecessor was 1750-3000rpm). The fuel consumption is 20.0km / L in WLTC mode (18.9km / L in the predecessor).
Interior of Volkswagen Golf
At Golf TDI, advanced equipment unique to the latest golf, such as the “Travel Assist” all-speed driving support system in the same lane and the digital meter cluster “Digital Cockpit Pro”, is standard equipment from entry grade. The seat will be given a fabric & microfleece seat exclusively for R-Line
The point of this TDI is the first adoption of the twin dosing (dual AdBlue injection) system. This is a system that injects AdBlue from two SCR catalytic converters (previously one) in order to suppress the emission of nitrogen oxides (NOx), which is a bottleneck in diesel engines. In other words, by mixing AdBlue with the exhaust gas, NOx can be decomposed into water and nitrogen.
Reason for adopting twin dosing system
The reason for adopting twin dosing with two systems in a series is that the conversion efficiency deteriorates depending on the exhaust temperature. It was said that it would be possible to remove 90% or more of NOx at an exhaust temperature of 220 to 350 ° C, but it was difficult to keep it in that temperature range with one system, which led to the introduction of the twin dosing system. background. Immediately after the cold engine starts or when the load is low, the AdBlue injector for the 1st SCR on the side of the engine starts.
On the contrary, when the load is high, the exhaust temperature will be around 500 ° C, so the AdBlue injector for the 2nd SCR provided in the underbody will operate. This is said to be in the system operating temperature range because the exhaust temperature is about 100 to 150 ° C lower than the position of the AdBlue injector for the 1st SCR. As a result, NOx emissions can be reduced by up to 80% while the consumption of AdBlue is the same as before, and it complies with the EURO6d emission regulations.
In addition, the radiator efficiency for low-pressure EGR has been improved by 25% to further reduce the generation of NOx. The high-pressure injector with a maximum of 2200 bar is finely controlled, such as injecting 9 times per combustion cycle. In addition, noise and vibration countermeasures such as improving silencers and sound-deadening materials are also evolving.
