Electrochemical measuring device for determining the oxygen content in gases

US4368431A · kind A · utility

Assignee

• Brown, Boveri & Cie AG · DE

Inventors

• Franz-Josef Rohr · Weinheim, DE
• Rudolf Krapf · Leimen, DE

Key dates

• Filing date: Nov 13, 1980
• Grant date: Jan 11, 1983
• Expiry date: Nov 13, 2000

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N33/0016
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Electrochemical measuring device for determining the oxygen content in gases with approximately constant pressure, especially in combustion exhaust gases, with an oxygen ion-conducting solid electrolyte having two electrodes connected to a voltage source, and measuring changes in current. In combination with the electrical measuring device, a constriction is disposed in the path of the constant pressure gas stream with the constriction having a passageway of cross sectional area to pass the gas stream at the velocity of sound under the condition of critical pressure ratio dependent on a ratio of the pressure at the outflow side of the inflow side of the constriction which brings about sound velocity of the gas stream.