Numerical Simulation And Analysis Of Temperature Field Of Continuous Temperature Measuring Sensor

In the process of continuous casting, the temperature of the liquid steel in tundish is a key factor to the quality of steel product and the current production. At present, the continuous temperature measuring sensor for liquid steel is widely used, because of its structural simplicity,, stable performance, high precision, low cost and capacity to provide continuous temperature values. However, for its own structure, the temperature sensor has the long time thermal inertia, which causes the lag in the course of temperature measurement and then leads to fallibility measurement. For compensating the dynamic error introduced by the lag, this thesis discusses dynamic characteristics of the continuous temperature measuring sensor, and provides theoretical basis for the sensor's optimization design and practical use.This thesis first analyzes the heat transfer process of the sensor, builds the sensor-based thermal differential equation. Secondly, builds the theoretic math model by the equation and its boundary condition and initial condition. Thirdly, uses the ANSYS finite element analysis software to numerically simulate the model, studies factors that influence the temperature measurement accuracy and dynamic characteristics, such as ectonexine structure, physical parameter, initial and boundary condition, and builds the thermal analysis model. Comparing the simulation results to field data of the steel factory, the thesis gives out the temperature response function of the continuous temperature measuring sensor.For verifying the conclusion of numerical simulation, the thesis uses the field data of tundish temperature from Tangshan Iron and Steel Company as the contrast data, and the comparison result shows that the relative temperature error of simulation result is less than 1%, which means the model is correct. The residual of the temperature response function is less than 10℃, therefore the dynamic error of temperature sensor measurement can be estimated accurately.For applying the result for numerical simulation, the thesis proposes the further analyzing method to the interface temperature filed between steel slag and liquid steel in. the tundish, derives the vertical temperature variation in the liquid steel layer and multi-layer steel slag layer theoretically, proves the feasibility of the temperature gradient analyzing method for the detection of the interface between steel slag and liquid steel, provides the theoretical。basis for temperature gradient based liquid level detection.