Method for monitoring moving heat source and temperature field in workpiece machining process in real time

Abstract

The invention discloses a method for monitoring a moving heat source and a temperature field in a workpiece machining process in real time, and relates to the technical field of thermal state monitoring in the workpiece machining process, and the method comprises the following steps: S1, measuring the temperature of a workpiece; s2, establishing a workpiece heat transfer model; s3, establishing a workpiece thermal state evolution state equation containing the time-varying input matrix and an observation equation; s4, obtaining a (k + 1) moment temperature state priori estimation by using the heat source item intensity estimation value at the k moment, and calculating to obtain a Kalman gain, a temperature state posteriori estimation and a posteriori estimation error covariance; and S5, obtaining a measurement residual error sequence according to the temperature state priori estimation at the moment k and the temperature measurement value at the moment k + 1, calculating a correction gain matrix of a recursive least square method, and obtaining a heat source item intensity estimation value at the moment k + 1 in combination with the residual error. According to the method, the Kalman filtering and the recursive least square method are combined, real-time reconstruction of the moving heat source and the workpiece temperature field can be achieved, and the problem that a traditional method cannot achieve real-time reconstruction is solved.

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