K
Kermit
Guest
Professor Fleeming Jenkin's "fuel engine" patented 1874, is based on the same principles as the Stirling engine, and its main points can be understood from Fig. 86.
The upper part of the plunger or displaccr D contains the regenerator of wire gauze R, between the fire-brick lining B and the cooling chamber A. The combustion chamber H is lined with fire-brick, and being always kept at a white heat, fires the explosive gaseous mixture. In the passage between A and the working cylinder C, there is a slide-valve which regulates the admission of hot gaseous products of combustion to this cylinder.
Separate pumps a and g are used to compress the air into A, and the fuel into the combustion chamber H ; the gas directly by the pipe f, and the air pumped by pipe b to C and through R.
Air, petroleum, or even comminuted coal dust may be used as fuel, but ordinary coal gas will do.
The working substance is heated at constant volume to high pressure, and then allowed to expand. The action is as follows :
The charge of air is pumped into the cooling chamber A, and forced, by the rise of the displacer D, through the regenerator, where it is heated, into the chamber H, where it ignites with the charge of gas or petroleum which has been pumped into H by g. The displacer D is now at the top and the piston P near the lower part of its travel. The products of combustion are admitted at high pressure into the working cylinder C, and drive up the piston P, doing useful work. Near the end of this working stroke the valve between C and A opens the passage for the burnt products, which are then driven through the regenerator, giving up their heat to it before they escape into the exhaust or chimney during the return stroke of the working piston P.
A fresh charge of air is again forced into the cooling chamber and goes through the same operation. The ignition port i is used until the chamber H is hot enough to start combustion.
The use of the regenerator, combined with internal combustion, is a great step in the right direction, as the latter expedient prevents the waste of heat in its transmission from the fuel across metal plates to the working fluid. However, there are a great many difficulties to be overcome to make such an arrangement practically successful.
Professor Fleeming Jenkin, assisted by Mr. A. C.
