COZBY ENTERPRISES, INC.

By R. David Cozby     December 07, 2010

An Introduction to: “Understanding the Rankine Cycle”

(I recently sent a copy of the Site, “Understanding the Rankine Cycle” to my brother Dave.  The following is his reply. John)

John,
      I did read the material that you sent me and I am returning an article to you that probably explains what I think.
      I did not want to be a critic without at least offering some help. 
      I guess at first blush I think your article is way too technical for an introduction.  We are trying to sell a “car” not a textbook on how the engine, transmission, and differential works.
      So, my response would be: Simplify.  If someone wants more information, then you could be specific.
  Dave

      “Houston, We have a problem.  I have seen it in Denver, CO; Atlanta, GA; Chicago, IL; and yes, Houston too.  It’s a grey-brown haze that hovers over many urban areas and encroaches on our rural areas as well.  It’s smog.”
      Only a fool or liar would argue that mankind has not contributed to our environmental pollution.  Many are the voices that tell us so, but very few are willing or able to do anything significant to reduce our pollution.
      A great deal of this problem can be laid at the door step of the automotive industry.  Every internal combustion engine in existence from tiny little engines used in toys all the way up to huge stationary engines have one thing in common.  They are all terribly thermally inefficient.  That is to say that they all use more of their fuel to produce heat and exhaust than they use to produce useful work.  The amount varies according to the fuel and engine design, but all are rather poor in thermal efficiency.
      CozInc has a solution to much of this pollution.  CozInc has existed for quite some time, and the brain trust has been working on solutions for pollution for over 30 years.  CozInc’s solution is a self-contained, unitary, stand alone steam engine, boiler, condensation system.
      However, every time CozInc has offered their solution they have been met with a mind set stuck in the 1920s.  Whenever the word steam is mentioned people seem to automatically think of big, black, dirty, smelly, messy, Railroad locomotives.  CozInc’s solution is more modern than that.  Think closed-loop self contained recirculating steam systems.
      Many of our homes and industrial buildings are run on just such a system for heating that isn’t messy or smelly and at the same time producing much less pollution than internal combustion engines.
      One could also envision a well proven sealed recirculatory propulsion system used by the U.S. Navy on every one of their nuclear powered ships and submarines.
     Closed recirculatory systems are not unusual, even sealed systems that take a liquid to a gas and back again; — think refrigeration.
      The idea of a sealed recirculating steam system is not new.  The thing that is new with CozInc’s design is to make the complete system of boiler, engine, and condenser into a unit that is self contained, sealed, and easily moved from place to place or removed for repair.  CozInc is also proposing engines in various sizes to suit applications from lawn mowers and motorcycles, etc. to cars and trucks to large industrial applications such as heavy equipment, locomotives, and ships and even stationary engines.  In short, if it uses an engine, a CozInc engine can do it.
     CozInc engines are designed around a piston/cylinder engine because pistons and cylinders are much more efficient than turbines.  CozInc also likes steam because steam is water which is nontoxic when a leak will inevitably happen.
    A steam engine is an external combustion engine, so it can burn any combustible as fuel.  It isn’t restricted to a very specific exclusive fuel.  The thermal efficiency of a steam engine varies very little, if any, whether it is using gaseous fuel, liquid fuel, solid fuel, or even a nuclear reactor to produce steam.
     The efficiency of a steam engine hinges on how well sealed the system is, how well heat is retained, and how much work can be extracted from the steam before the steam condenses back to water.
     CozInc engine designs are in various configurations and various numbers of pistons.  All CozInc engines are estimated to be much more thermally efficient than any internal combustion engine, gasoline or diesel.
     Imagine if you would a world that has grasped the impact of a prime mover that does not pollute the atmosphere the way that gasoline and diesel engines do and not giving up any of the advantages that small, light internal combustion engines have provided us.  That world would still have motorcycles, cars, trucks, busses, trains, ships, small aircraft, heavy equipment all powered by sealed unitary recirculatory steam engines.  Stationary applications could go through another gamut from small portable power generation, to pumping water, to portable sawmills, to who knows what.
     Design and application particulars can be discussed on an individual basis.  Please feel free to contact us.

Thanks Dave,
John  

 Understanding the Rankine (ran’ - ken) Cycle June 19, 2007 - Rev. 6/28/12

   The terms “Rankine” or “Rankine cycle” are not familiar ones to the average American.  The term Rankine cycle comes from William John Macquorn Rankine (1820 - 1872), a Scottish engineer and physicist who first defined the thermodynamic cycle. 
   While the term, Rankine cycle, is unfamiliar the end product of the cycle in electrical power generation is very familiar.  Most of the electrical power that lights our homes is a product of the Rankine cycle.  Power plants generate steam to drive turbines which power electric generators that produce electricity.  The Rankine cycle is simply a closed loop steam cycle.  Liquid water is heated to steam, the steam expands through an engine producing work, the exhaust steam is then cooled back to it’s liquid state to be reused. 
   Even though the Rankine cycle is used world wide it retains a great deal of mystique.  In order to simplify understanding of the Rankine cycle it will be compared to something that is more familiar to us – refrigeration.  The Rankine cycle is closely related to refrigeration.  The two might be thought of as first-cousins.  Refrigeration comes in many sizes and applications.  A refrigerator uses refrigeration to keep food cool.  A freezer uses refrigeration to keep food frozen.  Refrigeration cools our cars, homes, businesses, and hospitals.  Refrigeration systems are safe, reliable, and give decades of constant service.  The following table shows the similarity between the Rankine cycle and refrigeration:   

                                                  Table 1.

   In refrigeration there are really two very similar cycles working together – one at each end.
The Rankine cycle produces the electricity.  The refrigeration cycle uses the electricity to produce cooling.
   In advanced Rankine cycles there are additional stages and devices employed to improve the efficiency of the system, but the above illustration is still valid.  The Rankine cycle is not mysterious.  Anyone can understand the Rankine cycle.  Eventually everyone will.
 
   John A. Cozby      

          An appropriate degree of super-heat for the given expansion in each stage must be maintained so that the inlet steam and the exhaust steam are both superheated.  A high degree of superheat is required.  The following partial table is excerpted for illustration purposes and is to be used in conjunction with the flow diagram.

 MATERIAL BALANCE — FOR 1/8 CUT OFF 1st STAGE ( given as an example)
Stage/Function             1st-Inlet     1st-Ex’st     2nd-Inlet     2nd-Ex’st     3rd-Inlet     3rd-Ex’st
Steam Conditions @         3              5                  6              7                  8               9
Temperature °F              1200          591             1200          592             1200          439
°F Above Saturation        515          153               762          315               922           297
Pressure psia                 2800          375               375            47.3            47.3           3
Spec. Vol. cu ft/lb        0.3268       1.5663         2.6112       13.1828      20.9324    299.5

(Mass, lb/cycle = 0.0003895 for 4 inch stroke X .75 inch bore, @ 1/8 th cut-off,1st Stage.)

    1200°F steam jacketing is employed in the upper end of the 1st stage cylinder wall.  The inlet steam chest and cylinder anterior-inlet valve in all stages are at 1200 °F.  There is no possibility for condensation in the engine while in operation.  Other pressures and temperatures can be used.

Advantages of High Pressure Multi-stage Reheat Steam Engines
[Assuming the multi-reheat engines are designed and built right]
John A. Cozby       December 13, 2012

I.  Stages of steam engine designs [bears little relationship to the number of cylinders employed]
     1.  One stage (single stage or simple)[most uniflow engines]
     2.  Two Stage (compound)
     3.  Three Stage (triple)
     4.  Four stage (quadruple, or “quad”)
II.  The two designs dealt with here
     1.  Triple with reheating between each stage (two reheats)
     2.  Quadruple with reheating between each stage (three reheats)
III.  Erroneous opinions in support of single stage engines (prejudice for single stage engines)
     1.  Single stage engines are good enough (for what?)
     2.  Why would you need more than one stage? (Implying multi staging is superfluous)
     3.  Single stage is as good or better than multi-stage
     4.  Should go back to the “Stanley” engines
IV.  Erroneous opinions opposing multi-stage engines (prejudice against multi stage engines)
     1.  They are too complex
     2.  They are too expensive
     3.  They are too sluggish
     4.  Fanciful, won’t get high efficiency

Following advantages of high pressure multi-stage reheat steam engines:
V.  Advantage of high efficiency (great expansion by stages)
     1.  Will get high efficiency
     2.  Will get three or more times the mileage of the “Stanley”
     3.  Will approximate power plant efficiencies (have to do what power plants do; that easy)
VI.  Advantage of smaller furnace/boiler
VII.  Advantage of smaller condenser
VIII.  Advantage of less load on auxiliaries
IX.  Advantage of smaller fuel and water tanks
X.  Advantage of better utilizing higher pressure steam
XI.  Advantage of lower piston loads
XII.  Advantage of good efficiency at high loads
XIII.  Advantage of good lubrication and sealing
XIV.  Advantage of more uniform cylinder temperature
XV.  Advantage of not mixing oil and steam/water

The triple engine is best suited for automotive applications.  The quadruple is better suited for larger applications.  The quad runs at higher pressures.  The quad has higher expansion ratios.  The quad has an additional reheat.  The quad has an additional regenerative feedwater heater.  The quad is more efficient.  But, the quad is larger, more complex, and more expensive.

There are some valuable advantages to multi stage reheat steam engines.