Steam Engine

About how to build of a steam engine, I  must be said that the most greater energy "specification", that is to parity of volume of expansion, it is really that expounded by the vapor, even if the change of phase and the necessary energy of vaporization of the water and following condensation of the vapor during its operation slightly bring to inferior theoretical outputs in comparison to those of the cycle Brayton.

With reference to the e-mail of answer to the application of an experimenter on as to transform a normal combustion motor ( gasoline or diesel) in cycle motor Brayton, amount carried over the following passages:

"Using the warm air, as in the cycle motor Braytons, want us suitable volumes of air, or it need to reduce at the most the attritions, climbing on everything on spheres pads, almost impossible thing if You want to re-utilize and convert a normal combustion motor, or to work  for instance with a heater in which the inside pressure is of 20 atm and a special circuit of cooling in which the pressure both of 2 ,3 or more atmospheres.

Also this is not simple; the cup of the oil should be replaced with a more strong container, working at 2 or 3 or more atmospheres.

About the closing of the valve of aspiration fifty-fifty run it is not a problem, in the sense that can be closed end hips raced, englobing a greater volume of cold air; simply the phase of immission of the warm air in the second cylinder will result more "long" of that of immission of the compressed air in the first cylinder and the phase of expansion of the warm air, also being "cut" in the final succeed in producing a greater job however, with a good output (for the calculation of the theoretical output the same formula of the ideal thermal cycle can be applied), and smaller losses percentages owed to the attritions.

Necessity stays to check the pressure both of the heater and of the raffreddatore, to maintain the correct one I bring of compression, with an electronic  or elettromeccanico system ."

The simplest alternative however, to my opinion, it is that of the vapor, avoiding the boiler, that is the most dangerous component of a vapor motor, through a microinjector of water.

The heater, that doesn't necessarily have to have the form of a serpentine but can be a simple pipe closed to the extremities, filled eventually with iron straw hat to improve the  thermal exchange; it can be provided to an extremity of a  to introduce a small quantity of water in continuous way (for ex. 1 cm cube every 5 or 10 turns of the tree motor) at the working pressure (for ex.10 or 20 atm).

The elevated heat to which must be made to work will induce a rapids evaporation of the water and its transformation in dry saturated vapor.

Obviously such heater must have provided of safety valve that prevents from overcoming an established maximum pressure; however, in case of "yelding" of the pipe, limited however from the fins set to regular distance, an issue of vapor will be had but not of dangerous hot water.

Wanting to use instead of the solar energy  the combustion of the firewood, during the operation will be necessary to put a screen constituted by  two strong counters with glass in front of the used fireplace, to also avoid the danger to be invested by possible throws of vapor; a closed heater would be opportune however, even if systematized in a fireplace.

From the opposite side vapor will be had to tall temperature by to send to the motor of recovery, whose pistons will work all in phase of expansion; the output will be maximized reducing to the least one the phase of immission of the vapor in the single cylinders, in operation of the in demand power, and therefore maximizing the ratio of expansion of the vapor.

You could also obtain an output conversion ratio thermal energy - mechanical energy around 20%, that it would  not to be inferior to that real of the Brayton, kept account of the attritions; the general thermal output would be raised however, using the heat of the condenser (connected to the pipes of unloading) to produce warm water.

The main point is to test the heater filling it with cold water to a greater pressure of that of work, to verify the estate of the various connections.

To do this the micropump can be used for the immission of the water, that working to low temperature, could be built using for the little piston a semirigid rubber.

Important also a valve of "not return" of the water in proximity of the entry of the heater, to avoid, in case of yeldings, dangerous throws of hot water.

During the operation of the steam engine such micropump must be made to work in intermittent way, so that to introduce only water when the pressure of the vapor begins to go down so that to avoid dangerous accumulations of hot water.

One retries some correct operation it will be that to interrupt the immission of water and to verify the real lowering of the pressure of the vapor.

Through an opportune regulator of phase of the immission of the vapor in the cylinder of expansion, the power furnished by the motor can be regulated  in gradual and continuous way.

Such regulator can be type mechanic or electromechanic.

Construction of the micropump

useful links:

http://perso.wanadoo.fr/jean-luc.soumard/moteur_vapeur.htm

presentation vapor motors

http://perso.wanadoo.fr/jean-luc.soumard/bicylindre.htm#plans

plain of construction two piston vapor motor; enough to click on the titles of the technical schemes; it deals with a vapor motor for modelling but you/he/she can also be realized on greater staircase.

The "drawers distribution" typical of the vapor locomotives confers the maximum power and the maximum couple engine but it implicates a not elevated output, around the 10% ÷ 14% because it doesn't allow the vapor an enough expansion; to maximize the output is necessary to maximize such expansion.

http://perso.wanadoo.fr/jean-luc.soumard/machines.htm

to build machine-driven tool for modelling, numerical control hips

 return to the constructive characteristics