32 results about "Interflow" patented technology

The invention discloses a miniature soil hydrologic monitoring system suitable for a high-heterogeneity karst sloping field. The miniature soil hydrologic monitoring system comprises a miniature region, a miniature interflow collecting system and a miniature direct surface runoff collecting tank. The miniature interflow collecting system is inserted below a sloping soil profile rock-soil interface below the sloping field miniature region for collecting interflow above the rock-soil interface; the miniature direct surface runoff collecting tank is inserted at the position of a sloping soil profile, which is close to the earth's surface for collecting direct surface runoff. The bottom surface of angle steel of the miniature direct surface runoff collecting tank is in contact with the top surfaces of an aluminum-plastic panel and a thin aluminum panel in the miniature interflow collecting system, and the miniature direct surface runoff collecting tank and the miniature sloping field region are fixed together through screws at two sides. According to the miniature soil hydrologic monitoring system, direct surface runoff and interflow of the miniature sloping field region can be simultaneously measured, the difficulty that the soil hydrologic process is monitored on the high-heterogeneity karst sloping field is solved, and a platform is provided for researches on aspects of the hydrologic process, the soil and nutrient loss principle, the karst process and the plant water adaptive mechanism in such karst sloping field.

The invention discloses a system for measuring flow speed and flow of slope surface interflow. The system for measuring the flow speed and flow of slope surface interflow comprises a tracer agent feed facility arranged at the upper end of a slope surface runoff plot and an interflow collecting facility arranged at the lower end of the slope surface runoff plot. The invention further discloses the method for measuring the flow speed and flow of slope surface interflow through the system for measuring the flow speed and flow of slope surface interflow. The method comprises the steps that the tracer agent feed facility is arranged on the inner side of the boundary at the upper end of the slope surface runoff plot, a section with the width consistent with that of the plot and the depth reaching a parent material layer is dug in the lower end of the slope surface runoff plot, then the interflow collecting facility is mounted in the dug section, and the interflow of the whole runoff plot is collected and measured; the flow speed of the interflow is calculated according to the time from feeding of a tracer agent to first appearing in the collecting facility; the flow speed of slope interflow and the dynamic law of the slope surface interflow are revealed.

The invention relates to a method of decreasing sewage overflow in combined flow pipe, which is controlled by fuzzy control under the base of layered control principle. For decreasing the generation of sewage overflow in combined flow pipe, prior methods have many shortages. The invention makes use of the urban multi-pump pipe network system built by the urban GIS system to divide the multi-pump pipe network system into several layers; each layer can be divided into several water drainage cells; each water drainage cell solves the minimum problem of partial sewage overflow by using fuzzy control; finally the sewage overflow in the whole system area is controlled to improve the urban flood prevention and anti-waterlogging ability and establish the foundation of operation of combined water drainage system from hand to automation.

The invention discloses a method for simulating heavy metal behaviours in a drainage basin dynamically and quantitatively. On the basis of a heavy metal soil multi-element conversion dynamic model and a rapid heavy metal equilibrium hypothesis theory, the amount of liquid-phase heavy metals leached out of soil in a migration process along with a surface runoff, an interflow and a permeation flow, the amount of solid-phase heavy metals migrated to a riverway along with suspended sediments in the surface runoff after being adsorbed on soil particles in the migration process, the amount of heavy metals in the riverway removed from a water body through settlement action, the amount of heavy metals entering the water body from a sedimentary phase in a suspending manner, the amount of dissolved-phase heavy metals migrated from a high-concentration area to a low-concentration area through diffusion action, and the amount of heavy metals removed from the sedimentary phase through burying action are obtained by calculation; and furthermore, the heavy metal concentration in the researched drainage basin is obtained by performing computer simulation of various obtained heavy metal amounts.

The invention discloses a slope-varying type interflow three-dimensional simulation monitoring runoff test flume. The runoff test flume comprises a base, wherein a front movable support rod, a runoff groove fixing support rod and a slope adjusting spiral support rod are sequentially arranged on the base, and a group of runoff grooves are formed in the front movable support rod, the runoff groove fixing support rod and the slope adjusting spiral support rod. The slope-varying type interflow three-dimensional simulation monitoring runoff test flume can monitor the flow velocity of interflows in different depths and also can monitor the flow of the interflows in different depths. Flow velocity monitoring holes in the lateral sides of the runoff grooves and flow monitoring outlets in the front ends of the runoff grooves can monitor the reaching position of a trace agent which is thrown into the interflow from a trace agent pipe along with the interflow, so that the flow velocity and the flow of the interflow can be calculated out. Thus, three-dimensional monitoring on the interflow can be achieved.

The invention relates to an experiment instrument capable of observing the migration condition of a soil wetting front and performing layered collection on interflow. The experiment instrument comprises a soil bin, wherein a waterproof device (6) is arranged at the bottom of the soil bin. The experiment instrument is characterized in that a protecting net for preventing soil from side leakage in a rainfall process is arranged on one side surface of the soil bin; multiple interflow layered collecting devices (7) are connected with one side, located in the soil bin, of the protecting net; multiple flow guide devices (4) are connected with one side, located outside the soil bin, of the protecting net; each flow guide device (4) and the corresponding interflow layered collecting device (7) are arranged correspondingly; the other side surfaces of the soil bin are assembled by steel plates (1) and tempered glass (2). The experiment instrument can be used for collecting overland runoff, interflow at different heights of the soil layer and groundwater runoff in the rainfall process and observing movement of soil moisture through the tempered glass (2).

The invention discloses a system and a method for measuring a nitrogen and phosphorus migration flux of interflow. The method comprises the steps of measuring a unit-area runoff depth value and nitrogen and phosphorus concentration data of the collected interflow; normalizing the measured unit-area runoff depth value, and converting the unit-area runoff depth value into an interflow migration flux; and calculating the nitrogen and phosphorus migration flux of the interflow according to a set calculation condition parameter initial value and the unit-area runoff depth value as well as the nitrogen and phosphorus concentration data of the collected interflow, and performing cyclic calculation processing. According to the system and the method, the problems that the automatic measurement functionality of a conventional method is low, the flow of the interflow cannot be continuously measured, any slope cannot be continuously observed and the like are fundamentally solved; a measurement result can be quickly and accurately obtained in real time; the system and the method are suitable for indoor measurement and outdoor measurement, cannot be limited by terrains and have high popularization and application values.

The invention discloses a method for measuring interflow in forest soil, and belongs to the field of forest soil ecological study. The method is characterized in that the system utilizes the soil profile and consists of an interflow flow collecting groove, a flow guide pipe and an interflow collector, wherein the flow collecting groove is embedded into a soil body in different layers of the soil profile, the interflow is collected, and the interflow is guided into the collector for completing the collection of the interflow. The method has the advantages that the structure is compact, the system is reasonable, the method is simple, the realization is easy, a scientific and reasonable small-dimension measuring system is provided for the study of the forest soil hydrology process, the moisture and nutrient balance and moving and the like, and greater popularization and application values are realized in the fields of forest soil ecology, forest hydrology, water and soil conservation and the like.

The invention provides a method for eliminating landslide mass area terrace interflow. The method includes the following steps: a, excavating a drainage ditch on a terrace; b, laying a layer of clay in the drainage ditch; c, placing a drainage pipe with water seepage holes uniformly arranged on the peripheral wall by 180 degrees in the drainage pipe, enabling a face with the water seepage holes to be upward and a portion without the water seepage holes to be buried in the clay, and compacting the clay; d, laying a layer of gravel of 8-13cm in thickness on an upper half of the drainage pipe, and laying geotechnic cloth to wrap the gravel; e, laying a layer of straw and fly ash; f, backfilling soil and hierarchically compacting to be flat; arranging a transverse furrow along a ridge of a previous step of the terrace in each step of the terrace. By the method, surface water seeping in the landslide mass area terrace and interflow formed by the surface water can be effectively eliminated, so that technical obstacles when a landslide area is reclaimed to be a terrace are overcome. The method has the advantages of being low in cost, simple, convenient, high in efficiency, easy in operation and the like, and is convenient for large-scale popularization and use.

The invention discloses a method for estimating drainage basin average free water storage capacity through flow hydrograph. The method comprises the steps of dividing a session flood in actual measurement flow data of a drainage basin outlet station; dividing a surface runoff, an interflow and a groundwater runoff on the session flood hydrograph, calculating runoff depths of the surface runoff, the interflow and the groundwater runoff and obtaining the total runoff depth; calculating the net rainfall depth of the session flood; calculating a free water storage reservoir full storage area proportion in full storage runoff generation; calculating an outflow coefficient of the interflow through combination of a linear constraint relation between the outflow coefficients of the interflow and the groundwater runoff according to a proportional relation among the runoff depths of the surface runoff, the interflow and the groundwater runoff; and carrying out estimation to obtain a value of the drainage basin average free water storage capacity according to the outflow coefficient of the interflow and the free water storage reservoir full storage area proportion in full storage runoff generation. According to the method, the number of the parameters needing to be set is reduced, and the probability that same effect of different parameters occurs is reduced.

The invention discloses a novel 1.5 pump hydraulic system for an excavator. The novel 1.5 pump hydraulic system comprises a load sensitive system and a negative flow control system, wherein the load sensitive system comprises a swing arm 1, a bucket, a left walker, a right walker, a backup device and a bucket rod 1; the negative flow control system comprises a gyrator, a swing arm 2, a dozer blade and a bucket rod 2. The novel 1.5 pump hydraulic system is characterized in that a pump of the load sensitive system adopts a load sensitive variable pump which is a first pump; the structure of a valve body is a plate-type load sensitive structure; the first pump is provided with an unloading valve and a flush valve; a pump of the negative flow control system adopts a negative flow pump which is a second pump; the negative flow control system is a mid-way bypass system; the second pump is provided with a throttle valve; interflow of the first pump and the second pump is external interflow. By using the novel 1.5 pump hydraulic system, a part of wasted oil consumption can be reduced; the overall operability is improved; the targets of good composite operability, and capability of preventing air suction of the swing arms and the bucket rods are achieved.

The invention discloses a removable slope-varying testing device for observing overland runoff and stratified interflow. The removable slope-varying testing device is composed of a box body which soilis filled into, an overland runoff guiding component, a stratified interflow guiding system and a removable base and gradient lifting system component, wherein the box body which the soil is filled into is a cuboid tank body made of steel; the overland runoff guiding component is a Y-shaped overland runoff collecting tank; the stratified interflow guiding system comprises a partition layer, a stratified stainless steel waterproof stopping plate, an inserting groove, a PYC porous plate with holes, a gravel filtering layer and an interflow guiding pipe; the removable base and gradient lifting system comprises a base, polyester tires and a hydraulic lifting system. The removable slope-varying testing device disclosed by the invention has the characteristics of simple structure, convenient operation, low cost, ability to accurately separate overland runoff from interflows of all soil layers in a rainfall test process and guide the overland runoff and the interflows out, application to researching water and soil loss and stratified transportation rules of runoff under the manual simulation rainfall condition, and the removable slope-varying testing device has the advantages of better popularization and application prospect.

The invention relates to devices for collecting interflow. The devices comprise soil bins loaded with soil, the multiple devices for collecting the interflow are inserted in the soil to collect soil moisture at different points, and the moisture of soil, which cannot be seen by naked eyes, inside the soil bins is subjected to data collecting and analyzing. The devices for collecting the interflowcan be buried in the soil, can collect the soil at different depths and can analyze the water content of the soil, and thus the transfer situation of the soil wetting front and the response relationship of the soil wetting front to rainfall are reflected more objectively.

The invention provides a forming cathode for forming and processing a radial diffuser blade interflow channel. The forming cathode comprises a throat channel working section which is arranged at one end of the forming cathode and is used for processing a throat region of the blade interflow channel, a diffusion working section which is arranged in the middle of the forming cathode and is used forprocessing a diffusion region of the blade interflow channel, and a forming cathode mounting handle which is arranged at the other end of the forming cathode and is used for installing the forming cathode, the end part of the throat working section is provided with a flow guide end used for guiding electrolyte to flow. When a vibrating device drives the forming cathode to feed, the a throat area of the blade interflow channel can be firstly processed by utilizing the throat working section, and then the forming cathode continues feeding, and the diffusion region of the blade interflow channelcan be processed by utilizing the diffusion working section. The flow guide end can guide the electrolyte in the machining gap to flow out of the outlet of a channel uniformly, and the flow field disorder at the outlet of the channel is effectively avoided. According to the forming cathode for forming and processing radial diffuser blade interflow channel, the channel is subjected to electrolyticmachining, and a blade interflow channel can be obtained.

The invention relates to a novel slope runoff and interflow velocity measurement tracer release instrument, which comprises a base, a main supporting rod, a tracer barrel sleeve, a tracer barrel, a tracer bag, a tracer bag connection rod, a tracer bag connection rod frame, a handheld rotation rod terminal sliding and rotating shaft sliding shaft frame, a tracer connection rod frame general connection rod and a handheld rotation rod, wherein the tracer barrel is arranged in the tracer barrel sleeve; the upper part of the main supporting rod is provided with the handheld rotation rod terminal sliding and rotating shaft sliding shaft frame; and a handheld rotation rod starting-end rotation shaft sleeve is arranged in a handheld rotation rod terminal sliding and rotating shaft sliding groove of the handheld rotation rod terminal sliding and rotating shaft sliding shaft frame, and the handheld rotation rod sliding and rotating shaft is adopted for movable connection. The novel slope runoffand interflow velocity measurement tracer release instrument has the beneficial effects that one-time hand-control connection rod operation is achieved, five branch tracer bag connection rods can release the tracer smoothly and flexibly at the same time, and transverse and uniform release of the tracer at the upper end of a slope runoff test plot is ensured.

The invention provides a slope interflow simulation device and a method for simulating interflow. An existing interflow simulation device is difficult to really reflect the actual migration conditionof the interflow. In the invention, the above problem is solved. The device comprises a foundation groove and a slope control groove. The slope control groove is located above the foundation groove and sleeves the outer side of the foundation groove. A sealing component is arranged between the foundation groove and the slope control groove. The left end of the slope control groove is hinged to thetop of the left side surface plate of the foundation groove. A right arc surface plate matches with the right side surface plate of the foundation groove. A front sector plate and a rear sector platematch with the front surface plate and the rear surface plate of the foundation groove. The slope control groove can move up and down on the outer side of the foundation groove around a rotating shaft under the effect of an angle adjusting device so as to adjust a simulation slope. The two grooves adopt a transparent hard material and are provided with observation scale nets. A soil structure filled with the device is the same with an actual slope, and the structure with a thick soil layer in the upper portion of the slope and a thin soil layer in a lower portion is presented, which can trulyreflect the actual migration condition of the interflow.

The invention discloses an inner oil sump with a bimetallic-strip temperature control structure. The inner oil sump is characterized by comprising a shell and a bimetallic strip assembly, wherein an oil draining hole is formed in the shell; at normal temperature, the oil draining hole is closed by the bimetallic strip assembly; and when heated, the bimetallic strip assembly is subjected to bendingdeformation so as to open the oil draining hole. The inner oil sump disclosed by the invention has the beneficial effects that less components are adopted, the mounting is quick, and the cost is low;when the temperature of engine oil rises to the preset temperature, the oil draining hole is opened by the bimetallic strip assembly; the interflow of the engine oil in the inner oil sump and that inan outer oil sump is achieved; all the engine oil participates in circulation; the normal running of an engine is guaranteed; and the engine oil is prevented from cracking too quickly.

The invention discloses a runoff production calculation method in a unified mode of a variable runoff production layer. The runoff production calculation method comprises the following steps: vertically layering calculation units; the evapotranspiration capacity of the calculation unit is deduced; runoff production calculation is carried out on the vegetation interception layer; dynamically dividing a soil layer theta-n calculation domain into a domain I and a domain II according to a steady-state soil moisture profile, respectively establishing equations for the domain I and the domain II, representing formation and development processes of a soil-rock interface change runoff layer and a soil interlayer change runoff layer, and performing runoff calculation; according to the calculation method, the formation and development process of the interflow is finely described, so that unified description of full storage-excess infiltration runoff production and a conversion mechanism thereof is realized. According to the method, the problem that fine description and rapid forecasting of a production and confluence mechanism of a distributed hydrological model in sudden flood forecasting in the hilly region are difficult to consider at the same time is solved.

The invention discloses a field natural slope surface runoff and interflow monitoring device. The device comprises a test plot for separately monitoring surface runoff and interflow, a surface runoffcollecting device and a layered interflow collecting device, and is characterized in that the test plot for separately monitoring the surface runoff and the interflow is connected with the surface runoff collecting device and the layered interflow collecting device through flow guide pipes respectively. The device has the beneficial effects that the surface runoff and the interflow of different layers are separately guided out, the surface runoff can be collected and guided out without errors, meanwhile, the difficulty that the interflow cannot be accurately guided out originally can be solved, and the interflow of each layer can be accurately collected; the surface runoff collecting device adopts two-stage shunting and can collect surface runoff which is dozens of times of the volume of the pool; and the stratified interflow collecting device can continuously monitor stratified interflow by adopting a triangular weir crest principle.

The invention discloses a method for measuring interflow in forest soil, and belongs to the field of forest soil ecological study. The method is characterized in that the system utilizes the soil profile and consists of an interflow flow collecting groove, a flow guide pipe and an interflow collector, wherein the flow collecting groove is embedded into a soil body in different layers of the soil profile, the interflow is collected, and the interflow is guided into the collector for completing the collection of the interflow. The method has the advantages that the structure is compact, the system is reasonable, the method is simple, the realization is easy, a scientific and reasonable small-dimension measuring system is provided for the study of the forest soil hydrology process, the moisture and nutrient balance and moving and the like, and greater popularization and application values are realized in the fields of forest soil ecology, forest hydrology, water and soil conservation and the like.

The invention discloses a system for measuring flow speed and flow of slope surface interflow. The system for measuring the flow speed and flow of slope surface interflow comprises a tracer agent feed facility arranged at the upper end of a slope surface runoff plot and an interflow collecting facility arranged at the lower end of the slope surface runoff plot. The invention further discloses the method for measuring the flow speed and flow of slope surface interflow through the system for measuring the flow speed and flow of slope surface interflow. The method comprises the steps that the tracer agent feed facility is arranged on the inner side of the boundary at the upper end of the slope surface runoff plot, a section with the width consistent with that of the plot and the depth reaching a parent material layer is dug in the lower end of the slope surface runoff plot, then the interflow collecting facility is mounted in the dug section, and the interflow of the whole runoff plot is collected and measured; the flow speed of the interflow is calculated according to the time from feeding of a tracer agent to first appearing in the collecting facility; the flow speed of slope interflow and the dynamic law of the slope surface interflow are revealed.

The invention discloses a miniature soil hydrologic monitoring system suitable for a high-heterogeneity karst sloping field. The miniature soil hydrologic monitoring system comprises a miniature region, a miniature interflow collecting system and a miniature direct surface runoff collecting tank. The miniature interflow collecting system is inserted below a sloping soil profile rock-soil interface below the sloping field miniature region for collecting interflow above the rock-soil interface; the miniature direct surface runoff collecting tank is inserted at the position of a sloping soil profile, which is close to the earth's surface for collecting direct surface runoff. The bottom surface of angle steel of the miniature direct surface runoff collecting tank is in contact with the top surfaces of an aluminum-plastic panel and a thin aluminum panel in the miniature interflow collecting system, and the miniature direct surface runoff collecting tank and the miniature sloping field region are fixed together through screws at two sides. According to the miniature soil hydrologic monitoring system, direct surface runoff and interflow of the miniature sloping field region can be simultaneously measured, the difficulty that the soil hydrologic process is monitored on the high-heterogeneity karst sloping field is solved, and a platform is provided for researches on aspects of the hydrologic process, the soil and nutrient loss principle, the karst process and the plant water adaptive mechanism in such karst sloping field.

The invention relates to a method for detecting fresh and old water in an overland flow and an interflow. The method belongs to the technical field of water conservancy detection. According to the method, a fresh / old water ratio of the overland flow and the interflow is calculated, and moisture sources of the overland flow and the interflow is further deduced; the fresh / old water ratio of the overland flow and the interflow is derived by measuring the content of a tracer agent in a water sample; and the precision of the new / old water ratio of the of the overland flow and the interflow obtainedby adopting the method is high.

The invention discloses a stratified reservoir thermal density flow tracing method mainly comprising the following steps: drawing landform and grid and inputting information into computer software, selecting a basic equation needed by the flowing incoming flow, and selecting a turbulent model and parameters complying with calculation requirements; setting physical and thermodynamics properties of the incoming flow body according to the real conditions of the incoming flow body; adding a tracking agent in the computer software, and calculating a tracking agent motion convection dispersion equation and parameters thereof; setting the incoming flow tracing agent concentration A; selecting B% of the incoming flow tracking agent concentration as the contour border of the thermal interflow when the calculation is over, thus clearly displaying shape features like the interflow specific thickness and the central line specific position. The advantages are that the novel method can clearly display thermal interflow motion conditions including shape, thickness and central position, thus ensuring calculating accuracy.

The invention discloses a test plot for separately monitoring field slope surface runoff and interflow. The test plot is characterized in that an enclosing ridge, a retaining wall and an underground bottom plate enclose the soil of the test plot, surrounding ridges are arranged at a left end, a right end and a top end of the test plot, a retaining wall is arranged at the lower end of the test plot, the bottom plate is located at the bottommost layer of soil of the test plot, a surface runoff collecting tank is arranged between the lower end of the test plot and the retaining wall, and an underground layered interflow collecting device is arranged below the soil of the test plot and above the bottom plate. The test plot is advantaged in that a complete device for collecting the surface runoff and the interflow is supplemented, the surface runoff and the interflow of different layers are guided out separately, the surface runoff can be collected and guided out without errors, meanwhile,a problem that the interflow cannot be guided out accurately originally can be solved, and the interflow of each layer can be collected accurately.

The invention discloses a slope-varying type interflow three-dimensional simulation monitoring runoff test flume. The runoff test flume comprises a base, wherein a front movable support rod, a runoff groove fixing support rod and a slope adjusting spiral support rod are sequentially arranged on the base, and a group of runoff grooves are formed in the front movable support rod, the runoff groove fixing support rod and the slope adjusting spiral support rod. The slope-varying type interflow three-dimensional simulation monitoring runoff test flume can monitor the flow velocity of interflows in different depths and also can monitor the flow of the interflows in different depths. Flow velocity monitoring holes in the lateral sides of the runoff grooves and flow monitoring outlets in the front ends of the runoff grooves can monitor the reaching position of a trace agent which is thrown into the interflow from a trace agent pipe along with the interflow, so that the flow velocity and the flow of the interflow can be calculated out. Thus, three-dimensional monitoring on the interflow can be achieved.

The invention relates to the technical field of water and soil loss, and particularly relates to a rainfall erosion measuring box. The rainfall erosion measuring box comprises a box body and a tilting mechanism, wherein the box body is used for bearing soil, and the tilting mechanism is connected with the box body for pushing the box body to make one end of the box body lower than the other end of the box body; a drainage hole is formed in the end face at one end which is lower when the box body is pushed by the tilting mechanism; a water collector is arranged above the end face and used for collecting water reserved by inclining soil on the top face of the box body. The invention further relates to a soil erosion amount measuring method with the rainfall erosion measuring box. The box provided by the invention can simulate a field environment in a laboratory or other non-field environments to measure water and soil loss, particularly, data of direct surface runoff and interflow can be acquired, and thus the box is convenient for scientific analysis and research workers to use.

The invention relates to a tracer dispensing instrument for measuring the flow velocity of slope runoff and soil flow, comprising a base, on which a main supporting rod is arranged, and a hand-held rotating rod rotating shaft is arranged on the upper support frame of the main supporting rod, The rotating shaft of the hand-held rotating rod is connected to the front end of the rotating rod through the rotating shaft, and an initial state locking bolt is arranged on the upper end of the main support rod, and the initial state locking bolt cooperates with the initial state lock hole on the fixed hand-held rotating rod Position limit, the hand-held rotating rod is provided with an upper and lower groove on the hand-held rotating rod to connect the total connecting rod of the tracer connecting rod frame, and the total connecting rod of the tracer connecting rod frame is limited by the fixed shaft collar of the total connecting rod. Position, the fixed shaft collar of the total connecting rod is arranged in the middle of the main support rod; the present invention measures the flow velocity in the soil by using the tracing method of groundwater flow velocity measurement, and the instrument of the invention can be used for the measurement of slope runoff velocity. The tracer delivery can also be used to measure the tracer delivery at different levels of soil flow velocity.

The invention discloses a method for estimating drainage basin average free water storage capacity through flow hydrograph. The method comprises the steps of dividing a session flood in actual measurement flow data of a drainage basin outlet station; dividing a surface runoff, an interflow and a groundwater runoff on the session flood hydrograph, calculating runoff depths of the surface runoff, the interflow and the groundwater runoff and obtaining the total runoff depth; calculating the net rainfall depth of the session flood; calculating a free water storage reservoir full storage area proportion in full storage runoff generation; calculating an outflow coefficient of the interflow through combination of a linear constraint relation between the outflow coefficients of the interflow and the groundwater runoff according to a proportional relation among the runoff depths of the surface runoff, the interflow and the groundwater runoff; and carrying out estimation to obtain a value of the drainage basin average free water storage capacity according to the outflow coefficient of the interflow and the free water storage reservoir full storage area proportion in full storage runoff generation. According to the method, the number of the parameters needing to be set is reduced, and the probability that same effect of different parameters occurs is reduced.