Groundwater is a crucial sources of water supply,especially in arid and semi-arid areas around the world.With uncontrolled withdrawals and limited availability of these resources,it is essential to determine the safe ...Groundwater is a crucial sources of water supply,especially in arid and semi-arid areas around the world.With uncontrolled withdrawals and limited availability of these resources,it is essential to determine the safe yield of these valuable resources.The Hill method approach was used in this study to determine the safe yield the Neishabour aquifer in Khorasan Razvi province in Iran.The results showed that the safe yield in the Neishabour aquifer is 60%lower than the current pumping amounts during the study period,indicating that further overdrafts could result in the destruction of this aquifer.This highlights the importance of using the Hill method to estimate the permitted exploitation from other aquifers,thus preventing problems caused by over-extraction and maintaining stability of global groundwater levels.展开更多
In this study,influence of back-wall clearance,CWL(Critical Water Level)and air content in water on flow patterns in a pump intake has been investigated experimentally and theoretically for different cases.The statist...In this study,influence of back-wall clearance,CWL(Critical Water Level)and air content in water on flow patterns in a pump intake has been investigated experimentally and theoretically for different cases.The statistical data show that CWL for a two-phase flow is lower than that in the case of a single-phase flow at a relatively low flow rate,and as the flow rate increases,this trend turns out to be completely reversed.Fine experimental data obtained under conditions of subcritical,critical and supercritical flow rates have revealed that the larger the back-wall clearance is,the more vortices exist and the higher the vorticity of free-surface vortices is.For the smallest back-wall clearance,the flow coming through the inlet occupies most space under the pipe bell,and both this flow and the inflow coming from the back wall are asymmetric relative to a certain vertical line other than the axis.For the larger and the largest back-wall clearances,the flows coming from the inlet and from the back wall are almost symmetrical relative to the vertical axis of the pipe bell.The velocity distributions on two PIV measurement lines for different back-wall clearance magnitudes indicate that the smallest back-wall clearance influences the flow around the pipe bell.展开更多
The water level rising rate of Tangshan mine well significantly accelerated in 2010,and the ascensional range was obviously higher than that of the same period in previous years.From the view of groundwater dynamics a...The water level rising rate of Tangshan mine well significantly accelerated in 2010,and the ascensional range was obviously higher than that of the same period in previous years.From the view of groundwater dynamics and loading effects,and based on the water pumping( pouring) water test model and semi-infinite elastic space theory model under uniform load,the effects of grouting and loading of nearby building construction on the well water level were analyzed. Results show that grouting at a distance of 200 ~ 700 m to the well,with amount of 2500m3 per day and duration of 270 d,can cause an 8 ~ 11 m rise of well water level; and loading of large-area building construction can cause about a 4m rise of well water level. Through the analysis of these factors,we find that the water level anomalous rising of Tangshan mine well was relevant to grouting and loading of the nearby building construction. This study provides a scientific basis for anomalous rising analysis of water level of Tangshan mine well.展开更多
Diyarbaklr basalt aquifer is volcanic-rock aquifers which contain high quality water. It was main resources for Diyarbaklr city center drinking supply up to 2005. Somewhere, basalt aquifer groundwater is still used fo...Diyarbaklr basalt aquifer is volcanic-rock aquifers which contain high quality water. It was main resources for Diyarbaklr city center drinking supply up to 2005. Somewhere, basalt aquifer groundwater is still used for irrigation in rural areas of Diyarbaklr city. In the study, Diyarbaklr city center＇s （which is located on the Tigris river basin） basalt aquifer groundwater potentials and hydrogeological features are examined and modeled by using GIS programmer. Firstly, general geological data, meteorological data and general information about natural water sources are collected together, afterwards, logs of well drilled by public institutions and private individuals within the Diyarbaklr city center are analyzed. Static water level, dynamic water level and well pumps yields are classified in these logs. Then, thematic maps produced with the help of Arc Info Professional GIS programmer with geostatistical analyst tool. Groundwater source potential of Diyarbaktr is examined by means of these thematic maps. In hydrogeological research, productivity by aquifer features, water retention capacity and groundwater level data evaluated with geological structure of area are taken into consideration.展开更多
文摘Groundwater is a crucial sources of water supply,especially in arid and semi-arid areas around the world.With uncontrolled withdrawals and limited availability of these resources,it is essential to determine the safe yield of these valuable resources.The Hill method approach was used in this study to determine the safe yield the Neishabour aquifer in Khorasan Razvi province in Iran.The results showed that the safe yield in the Neishabour aquifer is 60%lower than the current pumping amounts during the study period,indicating that further overdrafts could result in the destruction of this aquifer.This highlights the importance of using the Hill method to estimate the permitted exploitation from other aquifers,thus preventing problems caused by over-extraction and maintaining stability of global groundwater levels.
基金supported by the National Natural Science Foundation of China(Grant Nos.51909132,52079140,51779257).
文摘In this study,influence of back-wall clearance,CWL(Critical Water Level)and air content in water on flow patterns in a pump intake has been investigated experimentally and theoretically for different cases.The statistical data show that CWL for a two-phase flow is lower than that in the case of a single-phase flow at a relatively low flow rate,and as the flow rate increases,this trend turns out to be completely reversed.Fine experimental data obtained under conditions of subcritical,critical and supercritical flow rates have revealed that the larger the back-wall clearance is,the more vortices exist and the higher the vorticity of free-surface vortices is.For the smallest back-wall clearance,the flow coming through the inlet occupies most space under the pipe bell,and both this flow and the inflow coming from the back wall are asymmetric relative to a certain vertical line other than the axis.For the larger and the largest back-wall clearances,the flows coming from the inlet and from the back wall are almost symmetrical relative to the vertical axis of the pipe bell.The velocity distributions on two PIV measurement lines for different back-wall clearance magnitudes indicate that the smallest back-wall clearance influences the flow around the pipe bell.
基金funded by the Earthquake Tracking Contract Orientated Task,CEA(2011020303)Science and Technology Project of Hebei Province(13275407D)
文摘The water level rising rate of Tangshan mine well significantly accelerated in 2010,and the ascensional range was obviously higher than that of the same period in previous years.From the view of groundwater dynamics and loading effects,and based on the water pumping( pouring) water test model and semi-infinite elastic space theory model under uniform load,the effects of grouting and loading of nearby building construction on the well water level were analyzed. Results show that grouting at a distance of 200 ~ 700 m to the well,with amount of 2500m3 per day and duration of 270 d,can cause an 8 ~ 11 m rise of well water level; and loading of large-area building construction can cause about a 4m rise of well water level. Through the analysis of these factors,we find that the water level anomalous rising of Tangshan mine well was relevant to grouting and loading of the nearby building construction. This study provides a scientific basis for anomalous rising analysis of water level of Tangshan mine well.
文摘Diyarbaklr basalt aquifer is volcanic-rock aquifers which contain high quality water. It was main resources for Diyarbaklr city center drinking supply up to 2005. Somewhere, basalt aquifer groundwater is still used for irrigation in rural areas of Diyarbaklr city. In the study, Diyarbaklr city center＇s （which is located on the Tigris river basin） basalt aquifer groundwater potentials and hydrogeological features are examined and modeled by using GIS programmer. Firstly, general geological data, meteorological data and general information about natural water sources are collected together, afterwards, logs of well drilled by public institutions and private individuals within the Diyarbaklr city center are analyzed. Static water level, dynamic water level and well pumps yields are classified in these logs. Then, thematic maps produced with the help of Arc Info Professional GIS programmer with geostatistical analyst tool. Groundwater source potential of Diyarbaktr is examined by means of these thematic maps. In hydrogeological research, productivity by aquifer features, water retention capacity and groundwater level data evaluated with geological structure of area are taken into consideration.
