Research Of Vertical Flow Rate Of Dynamic Molten Iron Based On Time Intervals Of Infrared Radiation

Pouring technology playing an important role in both quality and quantity of casting is the most crucial production process of the precise casting. While in the most casting factories of our country still flowed the way of the manual pouring work, serious over-pouring and under-pouring not only wasted a mass of molten iron, but also increase the re-melting cost of defective products.The best way to solve the problem of over-pouring and under-pouring is detecting and controlling flow rate and capacity of casting ladle tap-hole. Ordinary flow-meter cannot measure it because of molten iron’s1534℃high temperature and strong characteristic of erosion. So this paper has put forward and went in to a new idea of dynamic vertical molten iron flow rate measurement, which based on time intervals of infrared radiation of glow molten iron in the flowing course.At first, based on infrared radiation of molten iron, according to Plank’s law, the paper work out that the degree of radiation emitted in infrared band of molten iron occupied98.9%of the whole electromagnetic wave spectrum’s, which can deduce and prove the feasibility of adoption of infrared receiver to detect the time interval of the molten iron. Based on the analysis of hydro-mechanics molten iron flow in the process of casting, according to the theory of orifice outflow and Bernoulli equation, the paper established relational model between time intervals of infrared radiation and flow rate or liquid level in the casting ladle.Next, set up experimental platform, which included the selection of the length and position of blocking-light tube, the design of core devices of flow rate detection and the design of display devices of time intervals of infrared radiation. After having done a lot of experiments in the casting worksite, the analysis of experimental data confirmed the feasibility of the raising method to detect the flow rate and capacity of casting ladle tap-hole.At last, made a study of measuring accuracy, adopted Monte-Carlo Method to keep track of massive infrared radiation emitted by the fluid column top of molten iron, and establish probability model of infrared radiation transmission. The paper used MATLAB to simulate the algorithm in the Pseudo random numbers manner to accomplish the task of imitating the random process. Thus, apply the statistical methods for the number of light beams received by the infrared receiver, when the top of molten iron flow emitted10000light beams. And then, explain the different length and diameters to make a difference in the acceptance rate of infrared receiver and the accuracy of measurement.The theoretical analysis, field test results and algorithm simulation show the rationality and feasibility of the raising method for detecting vertical flow rate of dynamic molten iron, and also lay a researchful foundation for farther study of detecting and controlling the flow capacity of molten iron.