高速旋转粒化器表面相变流体的流动换热特性  

Flow and Heat Transfer Characteristics of Phase-Change Fluid Over a High-Speed Rotary Granulator

作　　者：吕义文 代茂林 朱恂[1,2] 吴君军 王宏[1,2] 丁玉栋[1,2] 程旻[1,2] 廖强 LÜYiwen;DAI Maolin;ZHU Xun;WU Junjun;WANG Hong;DING Yudong;CHENG Min;LIAO Qiang(Key Laboratory of Low-grade Energy Utilization Technologies and Systems,Ministry of Education,Chongqing University,Chongqing 400044,China;Institute of Engineering Thermophysics,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学低品位能源利用技术及系统教育部重点实验室,重庆400044 [2]重庆大学工程热物理研究所,重庆400044

出　　处：《工程热物理学报》2025年第2期491-499,共9页Journal of Engineering Thermophysics

基　　金：国家自然科学基金创新研究群体项目(No.52021004)。

摘　　要：离心粒化余热回收技术是最有前景的高温液态熔渣处理技术,而熔渣在粒化器表面上的流动换热是影响粒化质量的主要因素之一。为揭示相变工质在粒化器表面的流动换热规律,本文采用与熔渣具有相似特性的松香石蜡混合液为实验工质,借助红外热像仪捕捉液膜温度分布,获得了液膜的流动特征;采用过孔径滑环热电偶解决了高速旋转粒化器的温度测量难题,明晰了粒化器温度演变过程以及粒化器与液膜传热系数的动态特征。研究表明液膜在粒化器表面的运动轨迹为螺旋线。在粒化器底面与侧面交界处的液膜表面温度以及粒化器内壁温度同时达到最低值,在粒化器边缘处时二者温差达到最大。粒化器与液膜之间的平均对流换热系数为48~360 W·m^(-2)·K^(-1)。此外,本文首次实验证实了相变工质在粒化器表面凝固成壳后的重熔现象,这对高温熔渣的离心粒化特性研究具有重要意义。Centrifugal-granulation-assisted thermal energy recovery is considered as the most promising technology for the treatment of high-temperature molten slag.The flow and heat transfer of the slag over the surface of the granulator is one of the main factors affecting the quality of the granulation.In order to reveal the law of flow and heat transfer of the phase-change fluid over a high-speed rotary granulator,the rosin-paraffin mixture with similar properties to the slag was adopted as the experimental medium in this paper.The temperature distribution of the liquid film was captured with the help of infrared thermography,so as to obtain the flow trajectory of the liquid film.In order to solve the temperature measurement problem of the high-speed rotary granulator,a through hole slip ring with thermocouples was used.The evolution of the granulator temperature and the dynamic characteristics of the heat transfer coefficient between the granulator and the liquid film were clarified.The results showed that the trajectory of the liquid film over the granulator was a spiral line.The surface temperature of the liquid film and the inner wall temperature of the granulator reached lowest at the junction of the bottom and side of the granulator.But their temperature difference reached largest at the edge of the granulator.The average overall heat transfer coefficient between liquid film and granulator was 48~360 W·m^(-2)·K^(-1)In addition,this paper provided the first experimental confirmation of the remelting phenomenon of phase-change material after solidifying into a shell on the surface of the granulator,which was of great significance for the study of centrifugal granulation characteristics of molten slag.

关 键 词：离心粒化 相变工质 转杯粒化器 流动换热 

分 类 号：TK172[动力工程及工程热物理—热能工程]