Eliminating all the cooling of the surfaces lapped by the discharge of the steam is obtained an eff

The adiabatic ldoc duke transformation The adiabatic expansion of the vapor in the Mollier diagram The isobaric transformation The vapor pressure of water The isothermal transformation The transformation isochoric ldoc duke enthalpy and internal energy density of the water The engine Manson free piston double-acting Vapor Density ldoc duke water: considerations lateral
As the name indicates, the energy of the steam engine in the case of a "flow" or "one-way" is extracted without forcing the return of steam in its path, that is to say that the vapor always moves in one direction through the cylinder. As shown in fig.1, the steam supply enters ldoc duke from below in the hollow cover, heats the surfaces of the lid and then from the valve located in the upper part of the cover passes into the cylinder; the vapor follows the piston cedendogli its energy ldoc duke and after it has been expanded, comes out at the end of the stroke of the piston, through the discharge ports arranged at the center of the cylinder and controlled by the piston. In contrast, in steam engines ordinary steam has an action against the current, that is to say that enters into the cylinder head, follows the piston during its working stroke, and then returns with the piston in its return stroke to discharge through valves that open in the vicinity of the cylinder ldoc duke head. The counter flow or reversal of the exhaust steam causes a considerable cooling of the surfaces of the washing ldoc duke due to their contact with the exhaust ldoc duke steam wet. This cooling action involves a considerable initial condensation when the steam of the boiler steam is again entered to the cylinder ldoc duke for the next working stroke. In a motor-flow, all the cooling surfaces are almost completely avoided, and then the condensations in the cylinder are largely eliminated as is the need to employ different stages of expansion. The motors a flow can therefore be realized with a single phase of expansion, ldoc duke while the steam consumption does not exceed that of steam engines compounds and that of steam engines triple expansion.
Eliminating all the cooling of the surfaces lapped by the discharge of the steam is obtained an effect similar to that obtained with overheating. In ordinary engines, overheating is employed to overcome the above mentioned difficulties caused by the cooling of the surfaces of washing. Now, if this seems redundant cooling is avoided the need for steam heating. The use of a ring of lights or discharge slits in the cylinder ldoc duke allows to obtain a zone of discharge passage three times larger than that obtained by the use of the cassette or other types of valves. ldoc duke The result of this large discharge section is that the final pressure in the cylinder is that of the capacitor, in particular when it is avoided the use of long and narrow connecting pipes between the condenser and the cylinder. In other words, if the capacitor is arranged close to the cylinder and the discharge passage has a large cross section, it is possible to bring the pressure of the cylinder up to that of the capacitor. In order to form a correct idea of the size of the exhaust ports, one should imagine a piston valve of the same size of the working piston and a valve body of the same size of the working cylinder and the piston is moved by an eccentric having the same excursion of the engine crank. On average, the discharge takes place after 9/10 of the thrust and consequently the compression starts after 1/10 of the return stroke ldoc duke has been completed, or in other words, the compression extends to 9/10 of the race. It is evident that, by replacing the usual discharge valve with exhaust ports or slots in the cylinder, all the losses of dispersion on the exhaust ldoc duke valve and all dead volumes and surfaces of washing, which necessarily come from the use of a discharge valve dedicated, are avoided. The diagram indicator (Figure 3) shows un'adiabatica of saturated steam for the expansion line and un'adiabatica of superheated ldoc duke steam for the line of compression.
This is the best proof of the excellent thermal action of this engine. The excessive initial condensation, in an engine in the ordinary counterflow fed saturated steam, makes sure that the expansion line follows approximately the law of Mariotte. In the engine A-flow, using saturated ldoc duke steam, there is almost no initial condensation, so the line expansion resulting necessarily un'adiabatica and even more if the supply steam is superheated. Due to adiabatic expansion, the dry fraction of the steam after the expansion is very low. Therefore, in the case of steam having an initial temperature of 300 C