New Car Engine

[MrMag]

http://news.discovery.com/tech/new-car-engine-sends-shockwaves-through-auto-industry-110405.html#mkcpgn=rssnws1

[Doctor No]

But what a good comments. Not from idiots, as most on this forum.

[ramset]

Wild stuff

I think Member Evolvingape {Big Turbine Guy}
Would love to see this!
Thanks
Chet

[evolvingape]

Hi Chet,

I can take a hint

So... Wave Compression Engines...

They are complicated to design and build and in my opinion are not a good direction to go for a rotary engine. They will outperform an ICE but that is because an ICE is cr@p!

This link in the comments section is very informative:

http://www.gtsj.org/english/jgpp/v02n01tp01.pdf

The WCE is going to be a bottomless pit of money to develop properly. It has highly complicated porting and compression / decompression phases. Its time component for fluid to rotor interaction is very short requiring scavenging phases that add to the complexity of the design.

The combustion chamber is inside the rotor casing which means that the rapidly expanding gases from combustion are going to be converted to heat via compression. The link mentions operating temperature of 1070 C which is too hot. This will require exotic materials and so becomes expensive and certainly outside the budget of the guy working in his shed, which is most of us.

Read section 2 of the pdf: Steady and Unsteady Compression.

Basically a Tesla Turbine is an example of a steady state and the WCE is an example of an unsteady state. Unsteady can also mean Pulse Width Modulation as well as compression / decompression  mass flow phases.

I could not find reference to this in the article or pdf, maybe I missed it, but if they are going to use compression waves for ignition then the rotor must be spun up to speed by a prime mover to generate the pressure. Alternatively, they could combust the fuel with a spark maybe and the WCE would be a self starter due to the exiting hot gases causing deflection of the rotors chambers.

It is much more likely in my opinion that once running the WCE actually combusts via automatic ignition from such a high operating temperature (1070 C) and not compression waves.

Here is a link all about stainless steels properties, which is what is available to the common man and affordable:

http://www.azom.com/details.asp?ArticleID=2868

Heat Resistance of Stainless steel 316

Stainless steel 316 has good resistance to oxidation in intermittent service to 870°C and in continuous service to 925°C. However, continuous use at 425-860°C is not recommended if corrosion resistance in water is required. In this instance 316L is recommended due to its resistance to carbide precipitation.
Where high strength is required at temperatures above 500°C, grade 316H is recommended.

So, we can see that really we want to be keeping the temperature of 316 below 400 C if we can for peace of mind. With the automatic ignition temperature of Hydrogen being about 500 C then we would be aiming to keep it below 500 C to control the process (specifically LFV chamber priming pressure). Why that guy is saying the WCE can run on Hydrogen I have no idea because at 1070 C with a compressed oxidiser present (air) it would instantly ignite, so how he is managing the fuel injection to the chamber, without blowing himself up, I have no idea!

So, when you consider the chosen Hydrogen source for a WCE will probably be pure Hydrogen in a cylinder at pressure (hundreds of BAR maybe) and you consider that the only thing stopping a flashback will be the flashback arrestor, then you got a recipe for disaster.

This is exactly the same reason why you wont get me in a car running on compressed air, sure air cars work, but there is no way that you will get me sitting on a steel cylinder at 300 BAR. If your in a road traffic accident and that thing blows it will be like a very big bomb going off.

So, why is the RotoMax Hybrid different ?

Well first of all I removed the combustion chamber to the outside of the casing so we can control the temperature via external casing cooling, and we can also control the energy conversion phase and produce velocity and not heat as the product.

Inside the rotor the velocity is converted back to pressure and then back to velocity, repeatedly, over and over again. Every conversion there is a transfer of energy to the rotor via Impulse. This is basically an unsteady state that is constantly “fluxing”.

Then we have the PWM of the Hydrogen injection, and the PWM of the Water injection, both more efficient than a steady state burn, or compression forces from the restriction of expansion via combustion.

Next we have the Water providing cooling of the rotor via temperature differential balancing. The Water will be less than 100 C and the Hydrogen will be 500 C or less after exiting the Linear Firing Valve (actual temperature unknown at present but fingers crossed it will be 500 C or less). If it is over 500 C then the Water should bring that temperature down, and if the operating temperature of the RotoMax is less than 500 C then we are in business!

<500 C is important for two reasons, the automatic ignition temperature of Hydrogen (only applies to LFV and not rotor chamber) and the heat resistance of stainless steel.

We also have the viscosity and speed differential of Water and Hydrogen. By firing a pulse of Water into the rotor at low velocity, high mass flow rate, and then firing a pulse of Hydrogen into the rotor at high velocity, low mass flow rate, the Hydrogen will try to force its way through the Water. This should cause the two different fluids properties to try to balance and in so doing will lengthen the time component that the Hydrogen is interacting with the rotor and transfer more energy to the rotor.

The added bonus is that with Waters boiling point being so low, the high temperature of the Hydrogen should cause some instant vaporisation, and the resultant pressure increase of the Steam should maintain a higher pressure inside the rotor chamber, improving efficiency.

Then we have the cost of building the RotoMax, in the world of engines its going to be practically nothing! Once the prototyping has been completed the variables for most efficient operation will be known. A design file can be posted on the internet, on this forum for example, and anyone can download it. Take that file to a laser cutting shop and pay the money. Take the components home, assemble them, and a few hours later you got a working RotoMax Hybrid Engine. Kit parts can be put together and if the design is standardised by a community then we have a new cottage industry completely outside the control of anyone but us

These are some of the reasons why I have mentioned privately that I believe my work is a decade ahead of current thinking on these subjects, and why I expect the RotoMax Hybrid to outperform all known engines.

One thing I do know for sure, you wont get me working on developing a Wave Compression Engine anytime soon.

RM