Water demand increases continuously with an increasing population and economic development. As a result, the difference between water supply and demand becomes a sig- nificant issue, especially in arid regions. To fig...Water demand increases continuously with an increasing population and economic development. As a result, the difference between water supply and demand becomes a sig- nificant issue, especially in arid regions. To figure out the utilization of water resources in the arid region of northwestern China (ARNWC), and also to provide methodologies to predict the water use in future, three models were established in this study to calculate agricultural irri- gation, industrial and domestic water use in the ARNWC from the late 1980s to 2010. Based on river discharges in the region, the supply and demand of water resources at the river basin level were analyzed. The results indicated that agricultural irrigation demand occupies more than 90% of the total water use in the ARNWC. Total water demand increased from 31.97 km3 in the late 1980s to 48.19 km3 in 2010. Most river basins in this arid region were under me- dium and high water stress. Severe-risk river basins, such as the Shiyang river basin and the eastern part of the northern piedmont of the Tianshan Mountains, were found in this region. It was revealed that the water supply became critical from April to May, which was the season of the lowest water supply as determined by comparing monthly water consumption.展开更多
In this paper,an experiment system of wind-energy stirring heater has been designed and built.Its heating performance under the rotation speed of 300 r/min has been studied through changing stirring rotor’s layer num...In this paper,an experiment system of wind-energy stirring heater has been designed and built.Its heating performance under the rotation speed of 300 r/min has been studied through changing stirring rotor’s layer number or using different working fluids.With the help of CFD numerical simulation method,we studied the influence factors including temperature rise,total heat,heating power of each experimental group,and analyzed why these factors have such an effect.The results show:increasing the layer number of the stirring rotors can increase the motion intensity of working fluid and improve the heating effect;the quantity of effective working fluid in the rotor area can be increased significantly with the increasing of liquid level;the working liquid with high density,low viscosity,low specific heat capacity will be the ideal one.展开更多
基金National Key Project on Basic Research(973),No.2010CB951003The National Science and Technology Project,No.2014BAD10B06
文摘Water demand increases continuously with an increasing population and economic development. As a result, the difference between water supply and demand becomes a sig- nificant issue, especially in arid regions. To figure out the utilization of water resources in the arid region of northwestern China (ARNWC), and also to provide methodologies to predict the water use in future, three models were established in this study to calculate agricultural irri- gation, industrial and domestic water use in the ARNWC from the late 1980s to 2010. Based on river discharges in the region, the supply and demand of water resources at the river basin level were analyzed. The results indicated that agricultural irrigation demand occupies more than 90% of the total water use in the ARNWC. Total water demand increased from 31.97 km3 in the late 1980s to 48.19 km3 in 2010. Most river basins in this arid region were under me- dium and high water stress. Severe-risk river basins, such as the Shiyang river basin and the eastern part of the northern piedmont of the Tianshan Mountains, were found in this region. It was revealed that the water supply became critical from April to May, which was the season of the lowest water supply as determined by comparing monthly water consumption.
基金supported by the National Vegetable Industry System(No.CARS-23-C05)the Yangling Demonstration Zone Science and Technology Project(No.2018NY-09)the Key R&D Project of Shaanxi Provinc(2019TSLNY01-03)。
文摘In this paper,an experiment system of wind-energy stirring heater has been designed and built.Its heating performance under the rotation speed of 300 r/min has been studied through changing stirring rotor’s layer number or using different working fluids.With the help of CFD numerical simulation method,we studied the influence factors including temperature rise,total heat,heating power of each experimental group,and analyzed why these factors have such an effect.The results show:increasing the layer number of the stirring rotors can increase the motion intensity of working fluid and improve the heating effect;the quantity of effective working fluid in the rotor area can be increased significantly with the increasing of liquid level;the working liquid with high density,low viscosity,low specific heat capacity will be the ideal one.