基于伴随方程法的鱼饲料热特性参数反演  

Inversion of the thermal property parameters of fish feed based on adjoint equation method

作　　者：陈计远 王粮局[1] 王红英[1] 张国栋 王威 Chen Jiyuan;Wang Liangju;Wang Hongying;Zhang Guodong;Wang Wei(College of Engineering,China Agricultural University,Beijing 100083,China;COFCO Grains Holdings Limited,Beijing 100020,China)

机构地区：[1]中国农业大学工学院,北京100083 [2]中粮粮谷控股有限公司,北京100020

出　　处：《农业工程学报》2021年第19期316-322,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家重点研发计划项目(2018YFD0500600)。

摘　　要：比热、导热率和导温系数是鱼饲料重要的热特性参数,其在干燥及冷却工艺参数的调整、饲料湿热传递仿真模拟研究中均有应用。为了探究鱼饲料的热特性,同时探究反演算法求解饲料热特性的适应性,该研究以草鱼(成鱼)膨化饲料为研究对象,建立基于伴随方程法的反演模型;利用自行搭建的热传导试验装置并配合红外热像仪(测温精度±0.1℃),以获得饲料试样的温度分布规律;利用此数据可反演计算含水率为11%~17%的饲料在20~80℃温度范围内的比热、导热率和导温系数。使用差式扫描量热仪(Differential Scanning Calorimetry,DSC)和热特性分析仪分别测量饲料的比热和导热率,并计算导温系数,将此作为实测值;将反演算法所得值作为计算值。对二者进行线性拟合,决定系数R;均大于等于0.980,说明比热和导热率的计算值与实测值的误差较小,结果表明基于反演算法的鱼膨化饲料热特性参数测定方法是可行的。同时,结果表明,草鱼膨化饲料在11%~17%含水率和20~80℃温度范围内的比热为1.710~1.840 kJ/(kg·℃)。饲料比热随温度的增大而显著增大(P<0.05)。当含水率由11%增大至17%时,饲料的比热显著增加(P<0.05),且呈线性规律。饲料的导热率为0.086~0.148 W/(m·K),当温度由20℃增大至80℃时,草鱼膨化饲料导热率显著增大(P<0.05);含水率对其影响同样显著(P<0.05)。饲料的导温系数为5.701~10.003 m;/s,且受温度和含水率的影响均显著(P<0.05)。研究可为鱼饲料热特性参数的测定提供一种新思路。Thermal properties of feed and artificial experience have been generally considered, when adjusting the process parameters of hygrothermal treatment in the production of fish feed, including cooling and drying. Specific heat, thermal conductivity, and thermal diffusivity are the important thermal properties of fish feed. In this study, grass carp(adult fish)extruded feed was taken as the research object. The inversion algorithm was established to obtain the temperature distribution of feed using the adjoint equation. A test was also carried out using the self-developed heat conduction device and infrared thermal imager. When testing, the feed was quickly spread on the cast aluminum soaking plate, where the feed was closely arranged in a single layer, with a thickness of about 4 mm and a total of about 10 g. The infrared thermal images were captured for the feed layer surface and the upper surface on the cast aluminum soaking plate using the infrared thermal imager(accuracy±0.1℃). SmartView software was selected to process the infrared thermal images for the temperature-time data of the feed sample test surface(x=h) and heating surface(x=0), from the T-t data of heating surface x=0 and the feed sample test surface x=h. MATLAB software was selected first to solve the adjoint equation for the adjoint variables, then obtain the gradient value, and finally obtain specific heat c and thermal conductivity k. As such, the specific heat, thermal conductivity,and thermal diffusivity of feed were obtained, according to temperature distribution with the moisture content of 11%-17% and the temperature range of 20-80℃. The results show that the specific heat of grass carp extruded feed was 1.710-1.840 k J/(kg·℃). Specific heat of feed increased significantly with the increase of temperature(P<0.05). When the moisture content increased from 11% to 17%, the specific heat of feed increased significantly(P<0.05), indicating a linear law. The thermal conductivity of grass carp extruded feed was 0.086-0.148 w/(m·K). When th

关 键 词：反演 比热 导热率 导温系数 鱼饲料 

分 类 号：S816.8[农业科学—饲料科学]