Moisture in insulation materials will impair their thermal and acoustic performance, induce microbe growth, and cause equipment/material corrosion. Moisture content measurement is vital to the effective moisture contr...Moisture in insulation materials will impair their thermal and acoustic performance, induce microbe growth, and cause equipment/material corrosion. Moisture content measurement is vital to the effective moisture control. This investigation proposes a simple, fast, and accurate method to measure moisture content of insulation materials through matching the measured temperature rise. Since moisture content corresponds to unique thermophysical properties, the measured temperature rise varies with moisture content. During the data analysis, all possible volumetric heat capacities and thermal conductivities are enumerated to match the measured temperature rise based on the composite heat conduction theory. Then, the partial derivatives with respect to both volumetric heat capacity and thermal conductivity are evaluated, so that these partial derivatives will be guaranteed equaling to zero at the optimal solutions to the moisture content. Compared to the benchmarked gravimetric method, this proposed method was found having a better accuracy but requiring a short test time.展开更多
走航式海洋多参数剖面测量系统(moving vessel profiler,MVP)是一种集成程度和自动化程度都较高的海洋调查设备,能对海洋多要素进行同时观测,获得水平方向的高分辨率数据资料。由于温度和电导率传感器响应时间的不匹配,MVP下放速度过快...走航式海洋多参数剖面测量系统(moving vessel profiler,MVP)是一种集成程度和自动化程度都较高的海洋调查设备,能对海洋多要素进行同时观测,获得水平方向的高分辨率数据资料。由于温度和电导率传感器响应时间的不匹配,MVP下放速度过快(峰值速度4 m/s)而造成非常明显的盐度尖峰现象。本研究结合Fofonoff(F)法、时间常数指数递归数字滤波(Giles and McDougall,GM)法和Grose提出的盐度尖峰订正方案,提出了一种新的方法,即MCT(match conductivity and temperature response time)法,通过对压力、温度和电导率传感器进行响应时间的匹配来减弱盐度尖峰。将SBE-9型CTD资料作为标准,发现订正后的资料与CTD盐度曲线的互相关系数为0.917,误差比订正前减小80%。对比35°N断面修正前后的盐度资料,订正后温盐跃层处出现的低盐区域消失。MVP的应用比常规海洋调查仪器CTD对于海洋现象的观测更有优势。展开更多
文摘Moisture in insulation materials will impair their thermal and acoustic performance, induce microbe growth, and cause equipment/material corrosion. Moisture content measurement is vital to the effective moisture control. This investigation proposes a simple, fast, and accurate method to measure moisture content of insulation materials through matching the measured temperature rise. Since moisture content corresponds to unique thermophysical properties, the measured temperature rise varies with moisture content. During the data analysis, all possible volumetric heat capacities and thermal conductivities are enumerated to match the measured temperature rise based on the composite heat conduction theory. Then, the partial derivatives with respect to both volumetric heat capacity and thermal conductivity are evaluated, so that these partial derivatives will be guaranteed equaling to zero at the optimal solutions to the moisture content. Compared to the benchmarked gravimetric method, this proposed method was found having a better accuracy but requiring a short test time.
文摘走航式海洋多参数剖面测量系统(moving vessel profiler,MVP)是一种集成程度和自动化程度都较高的海洋调查设备,能对海洋多要素进行同时观测,获得水平方向的高分辨率数据资料。由于温度和电导率传感器响应时间的不匹配,MVP下放速度过快(峰值速度4 m/s)而造成非常明显的盐度尖峰现象。本研究结合Fofonoff(F)法、时间常数指数递归数字滤波(Giles and McDougall,GM)法和Grose提出的盐度尖峰订正方案,提出了一种新的方法,即MCT(match conductivity and temperature response time)法,通过对压力、温度和电导率传感器进行响应时间的匹配来减弱盐度尖峰。将SBE-9型CTD资料作为标准,发现订正后的资料与CTD盐度曲线的互相关系数为0.917,误差比订正前减小80%。对比35°N断面修正前后的盐度资料,订正后温盐跃层处出现的低盐区域消失。MVP的应用比常规海洋调查仪器CTD对于海洋现象的观测更有优势。
