(燕山大學 機械工程學院,秦皇島 066004)
摘 要: 研究鋁鑄錠凝固邊界熱交換的變化規(guī)律及數(shù)學模型,并對不同澆注溫度下凝固過程的溫度場進行模擬。利用實時數(shù)據(jù)采集系統(tǒng)獲得凝固過程中鑄錠和金屬模溫度變化歷史數(shù)據(jù),采用非線性反算法和一維傳熱差分法對試驗數(shù)據(jù)處理,建立界面換熱模型并將其應用于凝固溫度場模擬中。結果表明:在鑄錠表面凝固前后凝固界面熱流密度可分段用指數(shù)函數(shù)來描述其變化規(guī)律,而所建立的熱交換系數(shù)與邊界溫度的對應關系可更好地反映實際的傳熱情況。模擬結果與實驗測溫結果相符,驗證了該鑄件/鑄型邊界熱交換規(guī)律的可靠性。
關鍵字: 鋁鑄錠;熱交換系數(shù);凝固;溫度場
(College of Mechanical Engineering, Yanshan University, Qinhuangdao 066004, China)
Abstract:Abstract: The rules of heat exchange on the interface of casting and model were set up, and the solidification temperature fields were simulated. In the solidification process, the temperature history data of ingot and mold were recorded with a data acquirement system. Based on the experimental data, nonlinear estimation method and finite difference method of one dimensional heat transfer were adopted to form the model of interface heat transfer. With this model, the temperature field of the casting system was simulated. The results indicate that the heat flow in the interface of ingot and mold can be described by exponential function. The heat transfer coefficient related with boundary temperature is better reflecting the true state. The results of the simulation agree well with the measured values, which indicates that the models of the coefficient of interface heat transfer are reliability.
Key words: aluminum ingot; coefficient of heat transfer; solidification; temperature field


