The disc-seal single screw pump(DSSP)used in the field of high viscosity oily sludge transport has a huge advantage.However,there is no research on the pressurization characteristics of the DSSP at present,which makes...The disc-seal single screw pump(DSSP)used in the field of high viscosity oily sludge transport has a huge advantage.However,there is no research on the pressurization characteristics of the DSSP at present,which makes its application limited.In view of this,the pressurization process mathematical model of the DSSP was established based on the geometric model of the pump.By using this model,the pressurization characteristics of DSSP and the influence of working parameters on the pressurization process were studied combined with the principle of back-flow pressurization.Analysis results show that the instantaneous pressurization process could be realized mainly depending on the reflux pressurization from the outlet chamber to the pressurization chamber when the screw rotor rotating angle is located at-5°to+5°.The pressure in the pressurization chamber will increase with the increase of working parameters which include inlet pressure,outlet pressure,screw rotation velocity and dynamic viscosity of fluid medium in the area of flow-back pressurization.The screw rotation velocity and the viscosity of the conveying medium have significant effects on the peak pressure in the pressurization chamber,and the peak pressure in the pressurization chamber is proportional to the screw rotation velocity and the dynamic viscosity coefficient of the conveying medium.The proportional coefficient between the peak pressure and the screw rotation velocity is 6.29×10~4.The proportional coefficient between the peak pressure and the dynamic viscosity of the conveying medium is 6.28×10~6.展开更多
The Jesuits played an important role in the transmission of Western science and technology to China during the seventeenth and eighteenth centuries,though their impact on water technology has received scant attention ...The Jesuits played an important role in the transmission of Western science and technology to China during the seventeenth and eighteenth centuries,though their impact on water technology has received scant attention thus far.As a case in point,Sabatino de Ursis,Society of Jesus熊三拔,in collaboration with the Chinese official Xu Guangqi徐光啟,published in 1612 Hydraulic Methods of the Far West(Taixi shuifa泰西水法),the earliest book in China on Western water-lifting devices,which contained a detailed description of the Archimedean screw pump.While the impact of the Archimedean screw pump in China and Korea remained rather limited,the screw pump was used to drain water from gold mines in the Japanese Sado Island from as early as 1637.This fact became known in the West only in the very late 1800s when hand-colored picture scrolls about the Japanese gold mining process became available.These scrolls show various applications of Archimedean screw,which apparently were made according to the manufacturing instructions in Hydraulic Methods of the Far West.展开更多
基金supported by National Key R&D Program of China[NO.2020YFB2010002]National Natural Science Foundation of China[NO.51706247,NO.51975585]the Fundamental Research Funds for the Central Universities and the Opening Fund of National Engineering Laboratory of Offshore Geophysical and Exploration Equipment[NO.20CX02312A]
文摘The disc-seal single screw pump(DSSP)used in the field of high viscosity oily sludge transport has a huge advantage.However,there is no research on the pressurization characteristics of the DSSP at present,which makes its application limited.In view of this,the pressurization process mathematical model of the DSSP was established based on the geometric model of the pump.By using this model,the pressurization characteristics of DSSP and the influence of working parameters on the pressurization process were studied combined with the principle of back-flow pressurization.Analysis results show that the instantaneous pressurization process could be realized mainly depending on the reflux pressurization from the outlet chamber to the pressurization chamber when the screw rotor rotating angle is located at-5°to+5°.The pressure in the pressurization chamber will increase with the increase of working parameters which include inlet pressure,outlet pressure,screw rotation velocity and dynamic viscosity of fluid medium in the area of flow-back pressurization.The screw rotation velocity and the viscosity of the conveying medium have significant effects on the peak pressure in the pressurization chamber,and the peak pressure in the pressurization chamber is proportional to the screw rotation velocity and the dynamic viscosity coefficient of the conveying medium.The proportional coefficient between the peak pressure and the screw rotation velocity is 6.29×10~4.The proportional coefficient between the peak pressure and the dynamic viscosity of the conveying medium is 6.28×10~6.
文摘The Jesuits played an important role in the transmission of Western science and technology to China during the seventeenth and eighteenth centuries,though their impact on water technology has received scant attention thus far.As a case in point,Sabatino de Ursis,Society of Jesus熊三拔,in collaboration with the Chinese official Xu Guangqi徐光啟,published in 1612 Hydraulic Methods of the Far West(Taixi shuifa泰西水法),the earliest book in China on Western water-lifting devices,which contained a detailed description of the Archimedean screw pump.While the impact of the Archimedean screw pump in China and Korea remained rather limited,the screw pump was used to drain water from gold mines in the Japanese Sado Island from as early as 1637.This fact became known in the West only in the very late 1800s when hand-colored picture scrolls about the Japanese gold mining process became available.These scrolls show various applications of Archimedean screw,which apparently were made according to the manufacturing instructions in Hydraulic Methods of the Far West.
