摘要 |
<p>An apparatus consists of a thin-walled cylindrical metal conduit inserted into the path of the flowing hot gas with a thermal sensor positioned in the conduit along its axis. There are one or more smaller diameter thin-walled tubes positioned inside of the larger conduit over a portion of its length. The smaller tubes are concentric with each other and with the larger conduit and surrounded the sensor, so that there can be gas flow through the annular spaces between each of the tubes and between the sensor and the inner tube. Means are provided for causing a flow of hot gas through these annular spaces so as to bring at least the central small tube up to the temperature of the flowing gas and with it the temperature of the sensor.</p> |