Water Versus GASOLINE

The principle of water injection in engines is actually old hat for automotive manufacturers, and this technology is now experiencing a real comeback. The reason for this is the increasing demand for greater efficiency. The principle promises significant fuel savings, which will reduce CO2 emissions and increase performance. Röchling Automotive is accommodating these market requirements by designing a complete water injection system for gasoline engines.

Save Fuel and Improve Performance
The function of the familiar technology is simple but highly effective. Conventional gasoline engines use gasoline to cool the engine at high loads. As the name suggests, water injection replaces the fuel used for cooling with water. The water is also injected into the combustion chamber. In the combustion step, the liquid evaporates completely and cools the engine. In the Worldwide Harmonized Light Vehicles Test Procedure (WLTP), a test procedure for determining the exhaust emissions and fuel consumption of vehicles, this not only translates into significant fuel savings – CO2 emissions in the test cycle are also cut. As a result of the lower temperature in the combustion chamber, engine knock is also reduced in the high load range, making earlier ignition timing possible. This means that the gasoline engine can be operated optimally.

Currently, the system uses distilled water. However, Röchling Automotive is working on a solution that, in the future, will also be able to use soft mains water or be supplied with rainwater via various other channels in the vehicle. “We can envisage a whole host of possible combinations for water injection with our long-standing successful air-water management for the inside of vehicles. It simply depends on the requirements of the customer,” says Walter Kral, Head of Product Line Fluid Components & Systems.

Using the Tried and Tested to Come up with Something New
Röchling Automotive provides the entire water injection system, including the injection modules. This also includes the tank and the pump module. At the heart of the solution is the extremely important water tank. Engineers from Röchling Automotive use their experience in tank design to adapt the shape and capacity of the tank to the individual manufacturer’s requirements. In doing so, they make optimal use of the available installation space to ensure that the water has to be refilled as infrequently as possible. The experts can also draw on their expertise and advanced technology for the design itself – the anti-sloshing measures familiar from the company’s sophisticated SCR tanks are also used here and increase comfort. Likewise, the developers are also using an in-house solution to deal with a well-known winter problem – freezing in the tank. An auxiliary heater is often required to provide enough water, at temperatures below 0°C. The full tank heater from Röchling Automotive thaws the water across the entire surface of the tank as quickly as possible using little energy.

Looking Ahead
“By offering water injection as a complete system, Röchling Automotive is anticipating a foreseeable development as the demand for clean, efficient vehicles with gasoline engines will increase in the future,” says Vincent Mauroit, General Manager Innovation & Business Development. With its system solutions, the company is actively addressing the challenges of the future and simultaneously opening up new marketing segments. The market launch for the water injection system is planned for 2020/2021.


Walter Kral
Röchling Automotive
Head of Product Line Fluid Components & Systems
Phone: +39 0471 958-355

Photos © Visual Generation – shutterstock.com, Röchling