Simultaneous determining the temperature and partial pressures of four gases in the high-temperature gaseous mixture

Abstract

In this work we present a simple method for simultaneous determining the temperature and partial pressures of gases in the gaseous mixture using its transmissivity as input data. The method is focused on remote diagnostics in real time when combustion gas temperature and partial pressure can fluctuate rapidly over a wide range (∆T ∼ 1000 K, ∆ρ ∼ 1 atm). To demonstrate the method, the transmissivity of the mixture including the following gases: H2O, CO2, CO, and NO are considered. The conducted simulations are based on the HITEMP2010 database. It has been shown that potential accuracy of the method is equaled to 0.1% and depends only on the agreements between the theoretical and input (experimental) spectra of the gases. The error in determining the temperature depends linearly on the uncertainty in the input transmissivity: uncertainty of 5% leads approximately to 2% error in temperature.