An Electro-Optic Pressure Indicator

Publisher Website
Google Scholar
Abstract
The author describes improvements on a diaphragm type of engine pressure indicator. The indicator takes advantage of the fact that a polished metal diaphragm forming part of the combustion chamber wall will be deflected in the form of a spherical mirror when there is a pressure difference across it. Since the radius of the mirror is inversely proportional to the change of pressure, the intensity of a beam of light reflected from this diaphragm will vary with the pressure. By measuring the changes of intensity of the reflected light beam an indication of the change of engine pressure is obtained. A special direct‐current amplifier has been constructed which makes possible the use of the indicator at any engine speed. Charts are included which may be used to determine when operation of the indicator is closely linear.

This publication has 1 reference indexed in Scilit: