Do you still remember the cars in the past which had diesel engines? The driver had to preheat the diesel for what seemed like ages before starting the engine. The engines were loud, dirty and had a performance which was as lively as stale beer. Or what about the first automatic gearboxes? They reduced the engine performance, took a while to change the gear which seemed like a number of seconds and sometimes appeared to be uncertain about which gear to take. Today everything has changed.
Diesel engines have developed to become economic with a sporty performance. In fact the capability of modern automatic gearboxes makes it hard to think of reasons to even go back to a manual gearbox. These improvements were all made possible by new developments in technology. Whereas some developments are clear to see, others working behind the scenes are just as revolutionary, such as the fully integrated intercooler from MANN+HUMMEL.
Why is an intercooler necessary? As a result of turbocharging, modern engines achieve a higher performance with a lower fuel consumption. For this purpose the turbocharger compresses the combustion air before it flows into the combustion chamber. In this process, however, the air heats up to around 200 degrees centigrade which makes combustion inefficient and in the worst case can even cause engine damage. The solution? After compression of the air, the air has to be cooled down again. Up to now this was mostly handled by a direct charge air cooling which used the air stream to achieve the desired effect. The disadvantage of this is that at low speeds, in a traffic jam or in particular with high ambient temperatures the effectiveness of this method is reduced. The result is that the whole motor management has to be adjusted to ensure it can also handle high air temperatures. This naturally comes at the cost of efficiency and performance.
Due to this more and more car producers and automotive suppliers are looking at indirect charge air cooling. Here an additional cooling water system of the vehicle is responsible for the cooling, which makes a significant contribution towards making the compressed air available with a uniform temperature. This in turn enables the exact setting of parameters for the engine which increases efficiency, improves performance and in total leads to a more harmonious engine response. This method, depending on the driving style, can reduce CO2 emissions by up to 3%.
As early as five or six years ago I discussed this subject with my team and formulated some initial ideas. We were determined to know more about the possibilities and so we drew up concepts, conducted tests and broke new technological ground. Our objective was not to copy an existing solution, but to create something completely new.
And as a result MANN+HUMMEL with its fully integrated intercooler has now gone one step further than all previous alternatives. We have designed a complete system consisting of an intake manifold and charge air cooling in a single component for a new six cylinder engine of a premium car producer from southern Germany. In contrast to alternative mounted solutions where the intercooler is pushed into the intake manifold from outside, we have placed the cooler completely inside the intake manifold shells. The whole system is finally closed using hot-gas welding and can be fitted as a single component.
What are the advantages? Our fully integrated intercooler is characterized by a higher strength and has no seals to the outside. And the “inner values” also impress, whereby an especially small charge air volume, optimum air flow, low pressure drop and a temperature difference of maximum two degrees Kelvin across all the six cylinders serve to improve engine response and enable the possibility of adjustment to fine tune performance and efficiency. I am really proud of our end product which we were able to develop together with the customer. But I am even more proud of the development time and the way we were able to make the intake manifold ready for series production.
I have seldom worked in a team as motivated and committed as this. In the critical phase we were all ready for action each morning at 7.30 am – sometimes a little tired from the previous evening, but full of beans and new ideas. This was because naturally some things didn’t work out as planned or the simulation results on the computer didn’t stand up to reality. We constructed many prototypes and tested each change until our admittedly high standards were fulfilled. Then there were challenges which we had not really anticipated. A good example here is the bypass seal between the cooler and the intake manifold shells. Some proven solutions were not able to do the job and at the end it was the simple fitting capability which we were concerned about. Finally the solution was a seal in the form of a two-part component.
So you see, each new product has its own history. The fully integrated intercooler is certainly one of my favorites.