Calculation and Measuring of Piston Temperatures of Air-Cooled Two-Stroke Gasoline Engines

For a geometrically simplified piston model, temperatures in the crown center and at the first ring groove as well as the rotationally symmetrical temperature fields of the crown were first calculated according to the equation of Gintsburg (5) with the assumption of constant temperatures and conditions of heat transfer in the combustion chamber and at the cylinder fins for different sizes of cooled and uncooled pistons. The temperatures could be measured continuously by means of thermocouples located at 36 measuring points in the piston and 12 measuring points at the cylinder of a test engine of 80 mm (3.15 in.) bore up to an engine speed of n = 2800 rpm. In this way the agreement between the calculated and the experimental results could be checked.