The engines of today have to generate lower emissions and offer higher performance. MANN+HUMMEL supports its customers here with a new intake manifold which integrates numerous functions.

The requirements which modern engines have to fulfill are extremely demanding. They should generate fewer emissions under real driving conditions and at the same time have a higher performance. Therefore it‘s a good thing that the specialists at MANN+HUMMEL have developed a suitable solution. An active intake manifold which includes the complete intake section from the turbocharger to the cylinder head with a two-stage, indirect charge air cooling and a water injection. This contributes to ensuring that engines also meet future emission regulations such as the Euro 6d standard. Apart from that, the flexible arrangement of the components in the system offers considerable design flexibility.

Next development stage

In 2015 MANN+HUMMEL presented an active intake manifold with fully integrated charge air cooling. This concept forms the basis for the new system. In the new concept the pre-cooler and main cooler are designed to be self-containing. Crimping to the adjacent plastic components ensures the required stability. As a result, costs were reduced as there is no need for a bypass seal, tension anchors and a welding process. The compact design also requires less installation space and reduces weight.

Constant cooling

The engineers integrated two indirect charge air coolers in the intake system. This makes the system more compact, reduces the charge air volume and improves engine response. In comparison to a direct charge air cooling, the main advantage of the indirect charge air cooling is a more constant cooling performance over the dynamic range. Robust tumble flaps in the intake manifold  also serve to generate controlled turbulence of the air when it flows into the cylinders. Both measures are designed to improve the combustion process in the engine and reduce fuel consumption and therefore also CO2 emissions by up to three percent. A selfregulating bypass flap with two charge air ducts between turbocharger and electric booster compressor also improve low-end torque, i.e. providing of torque in the low rpm range. The complete system also includes the charge air ducts from the turbocharger to the pre-cooler and from there to the intake manifold with main cooler. They are equipped with AgileJoint connections which enable the required tolerance compensation. On the hot side the duct can also be fitted with an optional broadband silencer to eliminate undesired noise.

Water injection as an option

The use of an optional water injection system can be used to reduce raw emissions, to protect components at full load and to increase efficiency. Which of these benefits is in the foreground can be determined individually by the engine development department. With this variant a water filter, water rail and injectors are also integrated in the intake manifold. MANN+HUMMEL has transferred its experience over many decades in the area of liquid filtration to this new application. The multi-layer, fully synthetic MULTIGRADE filter media for water injection meets all requirements with regard to particle separation efficiency, dirt holding capacity, chemical resistance and mechanical stability. If required, an additional electric heater can be integrated into the filter housing to support the system during the defrosting process. This enables water injection to be used even at low temperatures.

Sectional view of the active intake manifold with dual integrated intercooler and water injection system

Charge air duct (hot side) with AgileJoint element for tolerance compensation

Stand-alone indirect charge air cooler as pre-cooler

Charge air duct (cold side) with AgileJoint element for tolerance compensation

Self-regulation bypass flap with two ducts to the electric compressor or second turbo charger

Self-containing indirect charge air cooler as main cooler (connected to low temperature cooling circuit)

Water injection system with plastic water rail and inline water filter (optional)

Intake manifold module including tumble flap system with electric plug-in actuator

Market success

The new system and its components have attracted a great deal of interest on the market. MANN+HUMMEL has already been nominated to develop an intake manifold with self-containing, indirect charge air cooler and also a stand-alone, indirect charge air cooler. First applications for the 4-cylinder diesel and gasoline engines of European engine producers are set to enter series production from 2019. Customers benefit from a high performance solution with integrated functions as well as a reliable partner with a global development and production network. MANN+HUMMEL has already planned the next development steps. Design improvements to the arrangement of the coolers will further reduce the number of interfaces.

Advantages at a glance

  • Concept to achieve the future CO2 emission targets

  • Increase engine efficiency by using an integrated charge air cooler

  • Enhanced low-end torque with an self-regulating bypass flap

  • Optimized control of the turbulence in the cylinder by tumble flap system

  • Higher performance thanks to water injection