为了分析双螺杆挤压膨化机内流体的温度变化过程及规律,该文利用流变学理论建立了非等温、非牛顿流体的数学模型,在螺杆转速为245 r/min,入口处压力为0.5 MPa时,分别取初始温度423 K,433 K和443 K条件下,以玉米为原料对流体的温度分布进行了仿真分析.分析结果表明:流体受挤压过程中温度上升了5K左右,其中啮合区升温较快,初始温度为423 K时流体的温度分布较均匀；3种初始温度条件下物料均以等温状态流出挤压膨化模头,并通过食品膨化试验验证了仿真结论.研究结果可为双螺杆挤压膨化加工提供参考.%To explore the fluid temperature change law of twin screw extruder, a fluid-temperature coupling model of non-isothermal Newton fluid was constructed based on the rheology theory. The temperature distribution discipline of fluid in the extruder was simulated with the initial temperature T at 423, 433 and 443 K, respectively. Results showed that the fluid temperature increased by 5 K, high temperature circle in meshing district expanded quickly. The fluid temperature was changed uniformly at the beginning of the screw extruder, then the fluid flow exited out of the extruder isothermally. Several optimum product conditions of twin screw extruder were verified with food expanding experiments. This research could provide references for twin screw extruder processing.
展开▼
