Comparing maximum pressures in internal combustion engines

Stanwood W. Sparrow, Stephen M. Lee
naca-tn-101
June, 1922


Thin metal diaphragms form a satisfactory means for comparing maximum pressures in internal combustion engines. The diaphragm is clamped between two metal washers in a spark plug shell and its thickness is chosen such that, when subjected to explosion pressure, the exposed portion will be sheared from the rim in a short time.

An Adobe Acrobat (PDF) file of the entire report:
http://naca.central.cranfield.ac.uk/reports/1922/naca-tn-101.pdf