ADEQUATE PISTON COOLING - Oil Cooling As a Means of Piston Temperature Control

INCREASING engine outputs have required methods to control the piston temperature. The work presented in this paper shows one successful means through the use of a piston of low conductive, correlated with an appropriate rate of piston cooling oil from the engine lubrication system.

The effects of coolant temperature, load, and speed over the propeller load curve, and a piston baffle, on piston temperatures are investigated by thermocouples silver soldered in a 6 x 6½-in. diesel, two-cycle piston. Tests indicate that the rate of cooling oil does not have to be excessive to secure adequate cooling. Substantiating data from an 8 x 10-in. diesel engine are given.

Steel piston designs for use with jet oil cooling are shown. These are for the 6-in. diesel on which most of the data for the paper were taken.