ABSTRACT

In August Porsche made the news with there new high performance hydrogen project. Their goal is developing a hydrogen powered engine for use in sports cars, or high performing SUV’s.

 

Now most companies working on hydrogen internal combustion engines are more focused on making efficient engines, that can replace are day to day cars. Not Porsche, Porsche wants to build an engine that can be used in there upper scale performance vehicles.

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INTRODUCTION

You see Porsche is working on a 4.4 liter twin turbo charged V8 which in theory will produce 590HP. That’s over 130hp per liter. Which is Some proper performance figures. And this is really impressive, you see manufactures have some serious challenges with hydrogen.

 

Although hydrogen contains nearly four times more energy by weight than petrol, it’s a gas so its volumetric efficiency is a lot less. In simpler terms, Hydrogen is more energy dense per KG, but it takes up more space per energy unit.

 

And there is another problem, they have to deal with. Hydrogen has relatively low ignition energy requirements, which is great when you want to build a fuel-efficient vehicle, but for performance applications its causes some problems, you see this low ignition energy means that as combustion temp rises chances of pre ignition or knock also rises.

 

And knock bad, knock very bad. So how did Porsche develop a high performing engine using Hydrogen as a fuel source?

 

Well as I stated previously hydrogen takes up more space in your combustion chamber, meaning that there is less space for air in the chamber, so what is the obvious answer, booooost. Forcing more air into the chamber.

 

You see with any engine the amount of fuel an engine can burn depends on the quantity of oxygen it can draw in, pressurizing the air intake with a compressor like a turbo or supercharger enables it to generate more power. And the same goes for Hydrogen sort of. You see for Porsche to get the same power from its simulated V8 when it’s running on hydrogen instead of petrol, it needed turbochargers that out performed your average turbo system.

 

This turbo system needed to deliver around twice the amount of air by weight of normal production petrol engine turbochargers. So they looked into F1, similar to the Mercedes amg project one this engine utilizes electrically boosted turbochargers. But to find the right combination, the engineers simulated four different layouts using electrically assisted exhaust gas turbochargers.

 

They ran each setup thru many tests and simulations and ended up with a really interesting system, and I'm sure its un like any thing you have ever seen before. So each bank of the V8 has its own Electric turbo. Now like I said this is F1 tech. An Electric turbo has a electric motor in which can spin the turbo shaft in places where the engine doesn’t produce enough exhaust gas to spool up the turbo.

 

This way there is no lag. But you see this system has 2 compressor wheels per turbo. This is how the turbo looks, and let me explain how it works.

 

So it looks kind of simple, but it actually quite a complex way of getting air into the engine. Inlet air is pressurized by one compressor first, then passes through an intercooler, and then through the second compressor, from which it gets forced into the intake. #Porsche #hydrogen #V8 #ICE