<b>Time constants determination and analysis for a ring-shaped temperature sensor in fixed bed</b> - DOI: 10.4025/actascitechnol.v25i1.2225

Abstract

A theoretical and experimental methodology was developed and made possible to evaluate and analyse the time constants of five thermocouples of a ring-shaped sensor installed in a fixed bed. In this sense, step disturbances were applied to the temperature of the air that flows across the sensor and the step responses were registered by periodic measures of temperature until the sensor reached steadystate. The time constants were evaluated by linear regressions of the sensor mathematical model. Both the mathematical model and the technique used for the adjustment of the time constants were satisfactory. Each thermocouple from the ring-shaped sensor has presented distinct time constants. The external ring-shaped thermocouple, r = 0,027m, and the central thermocouple, r = 0m, has presented the higher and the lower value of time constant, respectively, independent of the volumetric gas flow.