The λ = 1 concepts are the limitations of the maximum temperature at the exhaust valve, the turbine inlet, and the exhaust gas at the first catalytic converter. Enrichment of the mixture plays an important role because it limits the maximum exhaust gas temperature and allows the components beneath the overloaded level. In current, the knock blocks the fuel consumption optimization in gasoline downsizing engines. The “knocking” phenomenon makes a great difference in the future development of CO2-optimized gasoline engines.

 

MAHLE has combined the function of conventional hollow valve, cylindrical bore, and with an additional electronic machining process, an extended hollow cavity can be made in the valve head. The liquid sodium in the hollow space can dissipate the heat better when the engine is work. The hollow space is not filled with liquid sodium, so it can shakes as the valve moves, thus the valve head is cooled. The sodium also can dissipate heat while breaking down.

 

This technology can be used for both intake and exhaust valves, thus making the surface in the combustion chamber cooler and shift the knock limit, enabling a more optimal selection of the firing point in the design of the gasoline engine cycle. This set of device has a obvious advantage of consuming 3 to 6 percent less power than the conventional hollow valves. The Evo Therm valve is latest invention of the MAHLE team which applying the advanced technology.

 

MAHLE is leading the hollow valves sectors, and has many years of experiences. The EvoTherm valve is based on a conventional hollow valve. Though it is the latest invention to support engine manufacturers, it has to face many challenges in engine development.

 

The thermodynamic advantages and industrial feasibility of the MAHLE TopTherm valve are now being evaluated. This type of lightweight valve has many advantages, such as reducing friction in the valve train, thus leading to a reduction in consuming fuels by up to 0.5 percent. Due to a rigid, rotation-symmetrical surface and a large sodium filling space, the device has the capacity to reduce temperature at the thermally highly loaded component surface. Based on thermal simulations and temperature measurements, there seems to be a potential to reduce the disk temperature.