A series of bionic grooves based on bird wing, such as cluster spiral groove, multi-array spiral groove and flow-split spiral groove, are introduced to improve the film stiffness and sealing properties of dry gas seal...A series of bionic grooves based on bird wing, such as cluster spiral groove, multi-array spiral groove and flow-split spiral groove, are introduced to improve the film stiffness and sealing properties of dry gas seal. A theoretical model solved with Finite Difference Method （FMD） is developed to study the static sealing performance, such as film stiffness and leakage rate of these bionic groove dry gas seals. Then, a performance comparative study between the bionic groove dry gas seals and common spiral groove dry gas seal with different groove geometry parameters such as groove depth ratio, spiral angle and micro groove number under different average linear velocity at seal ring face and seal pressure is carried out. The closing force, film thickness and leakage rate of dry gas seals with bionic grooves and common spiral groove are measured experimentally. Results show that cluster spiral groove and multi-array spiral groove dry gas seals have superiority in the film stiffness and stiffness-leakage ratio compared with common spiral groove under the condition of high-speed and low-pressure, while flow-split spiral groove dry gas seal has no obvious advantages of performance. Film stiffness of cluster spiral groove dry gas seal and stiffness-leakage ratio of multi-array spiral groove dry gas are 20% and 50% larger than that of common spiral groove dry gas seal, respectively, which are verified by the experimental results.展开更多
Several spiral groove gas film face seals (SGFS) with different layouts are compared quantitatively to analyze their merits and faults and application behaviors. In addition, a parametric study on downstream mode SGFS...Several spiral groove gas film face seals (SGFS) with different layouts are compared quantitatively to analyze their merits and faults and application behaviors. In addition, a parametric study on downstream mode SGFS is conducted to determine its optimal parameters under certain working conditions. In tne computation of gas film pressure on the face, finite element method (FEM) is applied to adapt to complicated geometrical boundary.展开更多
目的验证ABI ViiA 7Taqman HBV-DNA检测系统性能,确定该系统是否稳定、准确、可靠。方法参考美国临床实验室标准化协会（CLSI）颁布的相关文件,从精密度、准确度、线性、可比性等方面对ABI ViiA 7Taqman HBV-DNA检测系统进行性能评价;...目的验证ABI ViiA 7Taqman HBV-DNA检测系统性能,确定该系统是否稳定、准确、可靠。方法参考美国临床实验室标准化协会（CLSI）颁布的相关文件,从精密度、准确度、线性、可比性等方面对ABI ViiA 7Taqman HBV-DNA检测系统进行性能评价;通过稀释标本直至低于检测下限进行定量检出限验证实验;并与质量目标要求和厂商声明的分析性能进行比较。结果ABI ViiA 7Taqman HBV-DNA分析系统的批内精密度（CV批内）分别为1.485%、1.990%和0.932%;总精密度（CV总）分别为1.876%、3.361%和1.891%;准确度最大偏移为-6.8%;r^2为0.998 3,回归方程为Y=0.974 8 X＋0.050 7,线性范围为1.00E2～2.00E8;定量检出限为100IU/mL;ABIViiA7与ABI7500两台PCR仪的可比性：P=0.115,r^2=0.994,线性比对直线回归方程为Y=0.987 2 X＋0.051 7。结论 ABI ViiA 7Taqman HBV-DNA检测系统具有优良的精密度、准确度、灵敏度、线性,与ABI7500检测系统有良好的相关性,可用于临床标本检测。展开更多
基金Acknowledgment The research is financially support by The National Key Basic Research Development Plan （973 Plan, 2014CB046404）, National Nature Science Foundation of China （51575490） and Key Program of Zhejiang Provincial Natural Science Fund Project （LZ15E050002）.
文摘A series of bionic grooves based on bird wing, such as cluster spiral groove, multi-array spiral groove and flow-split spiral groove, are introduced to improve the film stiffness and sealing properties of dry gas seal. A theoretical model solved with Finite Difference Method （FMD） is developed to study the static sealing performance, such as film stiffness and leakage rate of these bionic groove dry gas seals. Then, a performance comparative study between the bionic groove dry gas seals and common spiral groove dry gas seal with different groove geometry parameters such as groove depth ratio, spiral angle and micro groove number under different average linear velocity at seal ring face and seal pressure is carried out. The closing force, film thickness and leakage rate of dry gas seals with bionic grooves and common spiral groove are measured experimentally. Results show that cluster spiral groove and multi-array spiral groove dry gas seals have superiority in the film stiffness and stiffness-leakage ratio compared with common spiral groove under the condition of high-speed and low-pressure, while flow-split spiral groove dry gas seal has no obvious advantages of performance. Film stiffness of cluster spiral groove dry gas seal and stiffness-leakage ratio of multi-array spiral groove dry gas are 20% and 50% larger than that of common spiral groove dry gas seal, respectively, which are verified by the experimental results.
文摘Several spiral groove gas film face seals (SGFS) with different layouts are compared quantitatively to analyze their merits and faults and application behaviors. In addition, a parametric study on downstream mode SGFS is conducted to determine its optimal parameters under certain working conditions. In tne computation of gas film pressure on the face, finite element method (FEM) is applied to adapt to complicated geometrical boundary.
文摘目的验证ABI ViiA 7Taqman HBV-DNA检测系统性能,确定该系统是否稳定、准确、可靠。方法参考美国临床实验室标准化协会（CLSI）颁布的相关文件,从精密度、准确度、线性、可比性等方面对ABI ViiA 7Taqman HBV-DNA检测系统进行性能评价;通过稀释标本直至低于检测下限进行定量检出限验证实验;并与质量目标要求和厂商声明的分析性能进行比较。结果ABI ViiA 7Taqman HBV-DNA分析系统的批内精密度（CV批内）分别为1.485%、1.990%和0.932%;总精密度（CV总）分别为1.876%、3.361%和1.891%;准确度最大偏移为-6.8%;r^2为0.998 3,回归方程为Y=0.974 8 X＋0.050 7,线性范围为1.00E2～2.00E8;定量检出限为100IU/mL;ABIViiA7与ABI7500两台PCR仪的可比性：P=0.115,r^2=0.994,线性比对直线回归方程为Y=0.987 2 X＋0.051 7。结论 ABI ViiA 7Taqman HBV-DNA检测系统具有优良的精密度、准确度、灵敏度、线性,与ABI7500检测系统有良好的相关性,可用于临床标本检测。
