Combustor under pressure

Combustor under pressure

It's not easy for combustion engine manufacturers at the moment: In Europe, the USA and even China, emissions limits are being lowered and controls are being tightened, while at the same time electric drive systems that get their energy from batteries and fuel cells are rapidly gaining momentum. Electric pioneer Tesla was able to record over 300,000 pre-orders for its Model 3 just a few days after the new launch - a hype that is unprecedented in automotive history. Nevertheless, Hans Peter Lenz, the founder and director of the Vienna Motor Symposium, which took place for the 37th time this year in the Vienna Hofburg, summed up after the two-day lecture marathon: “The basis of the drive in the automobile will remain the combustion engine for a long time, certainly for another 20 to 25 years.” The more than 1,000 engine experts and top managers sent to Vienna by the world's largest automobile manufacturers agreed: The gasoline engine could still be dramatically improved in terms of efficiency and could be on a par with the diesel engine in terms of efficiency. The plug-in hybrid drive will establish itself as a “bridge technology” on the path to emission-free driving. And the diesel engine, which has recently fallen into disrepute due to various emissions scandals, still has enormous development potential. This should be exploited, among other things, through register charging, electrically operated compressors or an all-aluminum construction. Here are the current recipes from the vehicle manufacturers:

VW: Petrol engine with cylinder deactivation

The new 1.5 liter gasoline engines from the EA211 TSI evo series from Volkswagen will gradually replace the previous EA211 R4 TSI with a displacement of 1.4 liters from the fourth quarter of 2016.Friedrich Eichler, head of the 
Aggregate development at Volkswagen,points to the up to ten percent increase in efficiency compared to its predecessor as well as the consumption advantage of one liter per 100 kilometers. The efficiency-increasing measures: Miller combustion process with increased compression, exhaust gas turbocharger with variable turbine geometry, first use of the fourth generation common rail injection system with a pressure increased to 350 bar and cylinder deactivation ACT, which closes the inlet and outlet valves of cylinders 2 and 3 up to medium load ranges and deactivates the injection.

Porsche: smaller turbo boxer

Porsche is focusing on downsizing and has developed completely new turbocharged boxer engines for its new 911 Carrera and 718 Boxster sports cars. In the Boxster base model, the 2.7 liter six-cylinder naturally aspirated engine gives way to a 2.0 liter four-cylinder turbo engine with 300 hp and in the S model the 3.4 liter six-cylinder naturally aspirated engine gives way to a 2.5 liter four-cylinder turbo engine with 350 hp. Despite the downsizing, the engine output of both engines increases by 35 hp compared to their predecessors.Thomas Wasserbäch, Head of Boxer Engine Development at Porsche,promises consumption savings of ten to 13 percent compared to previous models.

BMW: strong signs of life 

Strong combustion engine signs of life at BMW too: The new 7 Series is powered by a 12-cylinder petrol engine in the top specification. The 6.6 liter V12 engine with 441 kW/600 hp and 800 Nm torque takes the top spot in the BMW Efficient Dynamics program thanks to its further increased dynamics combined with reduced fuel consumption. Alternatively, the 7 Series can also be ordered with a newly developed 3.0 liter six-cylinder diesel.Fritz Steinparzer, head of diesel engine development at BMW Steyr,presents the newly designed permanent two-stage turbocharging consisting of two low-pressure and two high-pressure exhaust gas turbochargers. The output thus increases from 280 kW to 294 kW (400 hp) with a torque of 760 Nm, and the consumption reduction is four to six percent.

Audi: real world premiere

Audi is presenting a real world premiere with its new V8 TDI: For the first time, the diesel engine combines turbocharging with an electrically driven compressor, enabling a sprint from 0 to 100 km/h in 4.8 seconds. The new V8 TDI generates its output of 320 kW with a maximum torque of 900 Nm from a displacement of 4.0 liters. The new engine will first be used in the Audi SQ7 with 8-speed tiptronic and quattro drive and is also intended for other group models.Andreas Fröhlich, head of V diesel engine development at Audi:“With the new engine, we were able to reduce consumption to 7.2 l/100 km and at the same time noticeably improve the engine and driving performance.”

Mercedes-Benz: Hybrid evolution

Mercedes-Benz is already presenting the third generation of its hybrid drives. A high-voltage battery can be charged at a socket and enables a purely electric range of a good 30 kilometers. The drive train is based on the new 9G-Tronic automatic transmission and combines a 65 kW electric motor with a turbocharged 2.0 liter four-cylinder gasoline engine with 155 kW. The maximum system power is 210 kW, reportedMario Mürwald, Head of Otto Engines and Hybrid Powertrain at Mercedes-Benz.

Hyundai-kia: Otto with more power

Hyundai-Kia introduces its new Kappa 1.6 GDI engine. LoudEngine developer Hwang-Bok LeeThe new gasoline engine achieves an outstanding efficiency of 40 percent. Key technologies include the Atkinson cycle with a high degree of compression, cooled exhaust gas recirculation (EGR), high-tumble intake ports, knock suppression and friction reduction. Hyundai-Kia will introduce the new engine in hybrid vehicles worldwide.

Mazda: downsizing for efficiency

Mazda presents the next level of downsizing with the Skyaktive-G 2.5T turbo petrol engine.Ichiro Hirose, head of powertrain development at Mazda,uses figures to demonstrate the efficiency advantages that Mazda has achieved through reduced internal engine friction, knock suppression and cooled exhaust gas recirculation as well as the so-called scavenging technology (overlapping opening times of intake and exhaust valves).

Honda: more power, less fuel

Honda has developed a new turbo GDI engine family with displacements of 1.0, 1.5, 2.0 and 3.5 liters for global use. Through the combination of turbocharging, gasoline direct injection, variable valve train and a combustion concept with a high degree of turbulence, performance could be increased and fuel consumption reducedHonda Senior Chief Engineer Tomonori Niizatoout of.

Control is better

From 2017 onwards, it will be possible to check whether the engine developers' full-bodied promises hold true using much stricter and more precise test methods than before. The previously applicable New European Driving Cycle (NEDC) will then be replaced by the expanded WLTP cycle (Worldwide Harmonized Light-Duty Vehicle Test Procedure). In addition, from September 2017, the new RDE measurements (Real Driving Emissions) will be mandatory, in which nitrogen oxides and particles as well as CO2 and consumption in real road traffic are measured using mobile measuring units on the vehicle. As Helge Schmidt from the internationally active German testing technology service provider TÜV Nord explains at the Vienna Motor Symposium, an RDE journey consists of an urban portion (34 percent), a highway portion (33 percent) and an intercity portion (33 percent), each driven at different speeds. The duration is 90 to 120 minutes. Apart from the engine load, the RDE measurement is influenced by numerous boundary conditions such as the environment, traffic, additional consumers and the behavior of the driver.