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Summer , hurican and going beyond carnot?

Summer , hurican and going beyond carnot?

Summer , hurican and going beyond carnot?

(OP)
Last two weeks was very fascinating. I read about some old developments of steam engine for cars. It it is very interesting what was develop on the first part of 20 century. The Doble brothers (specially Abner Doble) did amazing job on steam power car that even today, after 80 years, did not loose the "steam".

Here is couple links:
http://www.damninteresting.com/?p=669
http://www.stanleysteamers.com/doble_paper.htm
Some  characteristic of the steam propoltion use by Doble:
- simplicity (direct drive, no transmission, no clutch necessary)
- highest torque at zero RPM (like electric motors)
- very quiet operation
- fast startup (bellow 1 min)
- very low emission (Jay Leno have one of this vintage vehicle and test the emission - it pass current emission standard!!
Now the question is: can we replicate and improve the design of Doble?
The answer is yes.  There is the example.
Cyclone new steam engine for cars.
http://cyclonepower.com/drawings.htm

The introduction is just side not. As i said last two weeks I look in the steam engine properties and comparison to IC engines. What struck me that virtually all engines that we use are base on direct convention of heat to pressure , and pressure to mechanical power.
The question is; is using "pressure engine" the only way to convert heat in to mechanical energy?

The Carnot state that the bigger the differential of absolute temperature the highest the efficiency can be archive. Note that nothing is said about the pressure.
All the engines build today try to achieve highest efficiency eider by high compression ignition (Otto , Diesel...), or for external combustion high temperature to create high pressure. In both cases we have high temperature and pressure.
High temperature and high pressure create a lot of design problem. For internal combustion engine as well external combustion engine, pressure, temperature or both create physical efficiency limit that is almost impossible ever com.

Can we could got all that pressure with out temperature that will be grate.
However, temperature and pressure are lated.
Well,  we need some intermediate conversion that will substitute the pressure with something els.
How about velocity?
You can say: that what we exactly doing in side the engine, converting the pressure to velocity.
Engine is a converter of pressure to velocity otherwise kinetic energy.
And I believe, this is the problem. We using very inefficient method to convert pressure to velocity.
It will be nice if our system main source had the velocity or at list could be efficiently converted from pressure to velocity.
Are they system that can make convention of pressurized gas,  steam or fluid to high velocity low pressure? Yes. Are they efficient? Yes. Wat are this? Well, we have to look on Bernoulli's Principle that states: that for an ideal fluid (low speed air is a good approximation), with no work being performed on the fluid, an increase in velocity occurs simultaneously with decrease in pressure or a change in the fluid's gravitational potential energy.
http://en.wikipedia.org/wiki/Bernoulli's_principle
The Bernoulli's Principle provide the conversion of pressure to velocity. I am not sure if the temperature drop with increase of velocity. I assume it does (some one pleas clarify).
The  Bernoulli's Principle provide direct pressure to velocity convention.
That not all.
I just hiring about the Hurricane Din on news approaching Jamaica, and the weather man  explain how the hot water feed the hurricane with energy.   

Well , how about that? Hurricanes are vortex system.  The back pressure and the shape of enclosure encourage the gas or fluid to spin. Even  more interesting, there is some cooling action.
Viktor Schauberger made extensive research on vertex and it properties.
There is very interesting relation between the shape of enclosure and speed gain of  gas and fluids.
Even more interesting is comparison of attitude of of water to velocity and power.
Look on the example with the Dynamic Hydro power:
http://www.frank.germano.com/theschaubergerpage.htm
What we see is that vortex shape increase the velocity more rapidly then just attitude (pressure system).
We can see also that increasing in fluid speed will increase the energy exponentially in vortex system. In pressure system it is linear.
So now we have a system that convert high temperature and pressure to high velocity with low pressure, relatively low temperature.
Now is the question: can it be used?

One approach could be external combustion engine, possibly steam engine.
The components:
steam generator
vortex shape enclosure
turbine
The turbine is needed to convert the kinetic energy of gas to mechanical energy.  All the properties of wind turbine apply. That mean max energy efficiency of 57% (practical 40%) from wind at particular velocity. From vortex shape enclosure we should have some velocity gain (that mean power gain) that should offset the practical efficiency.

So what you think about that?

Miroslav Karas
NYC 08/19/2007

 



RE: Summer , hurican and going beyond carnot?

Any engine converts fuel into work. In a car the main work is moving it down the road. External combustion systems have to transfer the heat through metal walls in the boiler tubes. This takes time and has thermal losses. Gas engines expand air to move the pistons. Diesel engines stuff more air into the combustion chamber to provide a larger quantity of air to expand. Both gas and diesel engines suffer efficiency losses because air is not as good of a fluid as water to expand.
Beyond the engine converting fuel to heat the other problem is converting the pressure from the heat to do the work required. This work includes moving the vehicle, lights, engine and drive train component cooling, and passenger heating and cooling. One of the problems in converting the pressure to work is the range of speed and load needed at any given time in a drive cycle. Turbines and crankshaft engines work best at a relatively constant speed and load.
I hope to address these problems with my linear engine and hydraulic pump/motor. http://www.dehyds.com/html/linear_engine.html
http://www.dehyds.com/html/linear_engine.html
This week I’m learning Matlab, Simulink and other tools to simulate these systems to see if they can be made to work more efficiently than current systems.

Ed Danzer
www.danzcoinc.com
www.dehyds.com

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