COMBUSTION T13KE Ill THE ENGINE CYLINDER ENGINE PERFORMANCE

.4.s part of a gm.eral program to study combustion in the engine cylinder and to correlate the phenomena of cornliustion with the obserced performance of actual engine~, this paper, which was outlined by Mr. S. T. Sparrow, and the work undertaken at the reguest of the IITaiional Advisory Committee jor Aeronautics, presents a sketchy outline of what may happen in the engine cylinder during the burning of a.charge. It A-o suggests the type of information needed to supply the details of the picture and points owt ho-w combustion time and rate afect the performance of the engine. A theoretical concept of a flame front which is assund to mknce rzdidly from the point of ignition is presented, and calculations based on h area and wlocity of this flame and the density o.f the unburned gases are made to determine the mass ra~e of combustion. From this rate the mass which has been 6urned and the pressure at any in slant during combustion are computed. This process is then. raxrsed in an efort to determine actual rates of combustion and time relocii?ieafrom the pressures as recorded on hdicator diagrams. The efects ~f difereni rates of combustion on engine performance are then discussed and the imports nce of proper spark aduance is empliasixd