84 THE THERMODYNAMICS OF THE MARINE OIL ENGINE. 



Our brother engineers in other lines are conquering the air with their planes, 

 and space with their wireless spark, and are teaching us that the once indivisible 

 atom is really composed of hitherto unknown finer subdivisions. We, on the other 

 hand, are apparently contented with the wonderful efificiency of the present engine 

 and are discarding at least 60 per cent of our generated British thermal units 

 without any effort to recover this loss. This thermo plant is an attempt to profit 

 from objections found with the present internal-combustion engine and to conserve 

 as much as possible of this present waste energy. 



Briefly stated, in this new type of engine plant the starting energy is steam 

 generated in a special form of boiler. Before starting, the steam is admitted to 

 the jackets of the engine warming it to a point where starting steam can be used 

 without excessive condensation losses. After the engine is in operation from the 

 effect of combustion in the cylinder the flow through the jackets is reversed, 

 water from the bottom of the boiler is entered at the bottom of the jacket, and a 

 mixture of steam and water comes from the top and is returned to the boiler. In 

 this case combustion in the cylinder will not increase the temperature of the jacket 

 water but will transform it from water to steam at the same temperature. Also, 

 the exhaust gases from the engine will pass around and through this boiler before 

 being rejected, and as much as possible of this waste heat will be converted into 

 steam. The energy from the boiler will be used to run the auxiliaries and, if the 

 idea of the writer is correct, to run a separate steam propelling plant. The exhaust 

 from all steam units will be returned to a condenser, where at last the remaining 

 heat units will be abandoned as unavailable energy. 



In a plant of this type it will be possible to build units of great size with low 

 compression pressure. As has been shown in the early part of this paper, this can 

 be done without sacrificing any of the present thermal efficiency, but with a gain in 

 mechanical efficiency. The one chief objection which has not been overcome in 

 some form of a prime mover now in actual operation is the problem of lubri- 

 cation. With the crosshead type of engine and lubrication of the cylinder through 

 the piston it would appear that this problem would not be a hopeless one to solve. 

 Care would no doubt be needed to provide for the presence of water completely 

 covering the top of the cylinder head to prevent a steam pocket with a possible ex- 

 cessive temperature. This would mean the necessity of providing a more elaborate 

 system of circulation of cooling water than has been shown in the diagrammatic 

 sketch. The engine, as well as all piping, would be lagged to prevent radiation. 

 Increasing the temperature of the cylinder walls should have an effect to increase 

 the thermal efficiency of the engine itself. 



The writer is pleased to extend his thanks to Professor Peabody for his 

 kindness in going over this paper while in an embryonic condition and for his 

 valuable suggestions. The writer is also greatly indebted to Mr. W. C. A. Sieverts 

 and others, and especially to Dr. Geo. H. Ryder for invaluable aid given over an 

 extended period during which much of these data was collected. Many valuable 

 suggestions and much encouragement and aid have been received in the last twelve 

 years from Mr. F. R. Low, Editor of Power. 



