33 results about "Pressure propagation" patented technology

Unless an abnormality exists in piping introducing a pressure from front and rear of DPF 22 into a differential pressure sensor 45, pulsations of pressure propagation through an exhaust passage 21 is offset in a detection value of a pressure difference of the differential pressure sensor 45, and an amplitude of the detection value of the DPF pressure difference resulting from pulsation of the pressure becomes small. If a crack exists in one of the piping 3a and 3b, the influence of a pulsation of the pressure appears in the DPF pressure difference and the amplitude of the detection value of the DPF pressure difference becomes large. The amplitude of the detection value of the DPF pressure difference is compared with the reference value and is detected as being abnormal when it is large, utilizing the phenomenon described above.

A water leakage monitoring system including a water leakage position estimator which includes a periodic data acquiring unit for fetching predetermined-period flow rate pressure data stored in a monitoring device, and for fetching a signal related to a flow rate change and pressure changes expecting a water leakage reaction time calculating unit for calculating a pressure reaction time lag between two pressure changes, a pressure propagation velocity estimating unit for estimating a pressure propagation velocity using the pressure reaction time lag and a distance between two pressure gauges located in a water distribution block stored in a pipeline network map data, and a flow rate change position estimating unit for receiving a signal related to the flow rate change, and estimating a flow rate change position using pressure propagation velocity and a flow meter and pressure gauge locating positions of the pipeline network map data.

A canister is furnished to store evaporative fuel. A purge line is furnished to ensure that the canister communicates with an internal combustion engine intake path. The purge line is provided with a D-VSV (purge control valve) that controls the continuity of the purge line. Further, a check valve is furnished to control the pressure propagation from the intake path to the canister at the time of backfiring.

The invention relates to a strain gauge type pressure test tight oil inhibition experimental device, comprising a rock fixture structure and further comprising a control unit. The rock fixture structure can clamp rock containing tight oil and rotate around a horizontal shaft; a horizontal fracturing pipe runs from one side of the rock containing tight oil, one end of the fracturing pipe is connected with a fracturing fluid injection structure, and the fracturing pipe is provided with an inhibition cabin linkage sealing structure; the inhibition cabin linkage sealing structure is provided withmultiple resistance strain gauges; besides, a potential and resistance inhibition test structure is arranged above the rock fixture structure; the control unit can control working status of the fracturing fluid injection structure, the inhibition cabin linkage sealing structure and the potential and resistance inhibition test structure. The device can be used for testing oil and water displacement and oil production effect of fracturing fluid prepared based on different formulas, can analyze pressure propagation speed in inhibition process and oil and water displacement leading-edge position,and has a great significance in optimized evaluation on soaking effect of the fracturing fluid of different formulas.

An ink-jet recording apparatus includes a pressure chamber that contains ink, a nozzle communicating with the pressure chamber, which ejects the ink from the pressure chamber, an ink-jet head having an actuator that increases and decreases the capacity of the pressure chamber, and a driving signal generation unit that supplies the actuator with a driving signal to eject an ink drop from the nozzle. When no ink is ejected from the nozzle, the actuator is supplied with a very low pressure driving signal to increase the capacity of the pressure chamber and then return the increased capacity to an original size. The pulse width of the very low pressure driving signal is about twice as long as a pressure propagation time period during which a pressure wave in the ink propagates through the pressure chamber.

The invention relates to a method for simulating unsteady gas-water two-phase seepage in dual-media gas reservoirs based on pores and fractures. The core pore throat length and coordination number of the pore network model, the number of added fractures; the establishment of a pore-fracture dual-media model; the introduction of unsteady-state seepage theory and the combination of dynamic network simulation algorithm and unsteady-state seepage theory The gas-water two-phase seepage and pressure propagation process are simulated. The present invention simulates the unsteady gas-water two-phase flow on the basis of the pore-fracture dual-media model. In the traditional gas-water two-phase seepage process, the dynamic network simulation considering the fluid compressibility can more accurately describe the pore-level gas-water two-phase flow. Phase flow process; it can analyze the pressure distribution and pressure wave propagation of gas-water two-phase in the dual medium of pores and fractures, and help to study the flow law of fluid in pores and fractures.

The invention relates to a pressure propagation-based method for determining the drainage and production speed of coalbed methane at the initial stage of development, which comprises the following steps: 1) according to the relationship between pressure propagation distance and time, the time required for interwell pressure interference under a given well pattern and well spacing condition is determined; 2) According to the time required for interwell pressure interference obtained in step 1), the depressurization rate is determined according to the concept of balanced depressurization; 3) The depressurization rate of the wellbore liquid level is determined according to the depressurization rate obtained in step 2). The invention has a strict theoretical basis and realizes the quantitative determination of the coal bed methane drainage rate at the initial stage of development. The invention can be widely applied to the quantitative determination of the coal bed methane drainage rate at the initial stage of coal bed methane development in different reservoir physical property conditions.

The invention discloses a method for controlling the expansion of hydraulic fracturing cracks in underground coal mines. Arrangement of the expansion direction of the fracturing, (2) Grouting and sealing of the fracturing drilling and pressure-holding water injection drilling, (3) According to the calculated pressure-holding hole water injection pressure and single-hole pressure-holding water injection time, the pressure-holding water injection drilling (4) Hydraulic fracturing of the fracturing borehole. In the present invention, a number of boreholes are preset on both sides of the fracturing borehole according to the artificially expected expansion direction of hydraulic cracks, and pressure-maintaining water injection is performed on them before formal fracturing, so that a continuous band is formed around the fracturing borehole. In the high pore pressure area, hydraulic fractures can be induced to expand along the high pore pressure area, increasing the effective fracturing range; at the same time, reducing the crack initiation and expansion pressure of the fracturing drilling hole, reducing the damage to the coal seam roof and floor strata.

PURPOSE: A ring body for suppressing the propagation of earth pressure, an installation structure thereof, a disc cutter, and a front wheel device are provided to suppress the propagation of earth pressure to a rotation sliding part arranged inside the ring body. CONSTITUTION: A ring body(10) for suppressing the propagation of earth pressure comprises a first ring part(12) and a second ring part(13). The first ring part is composed of an elastic body. The second ring part is fixed to the side surface of the first ring part, and is composed of rotatable metal. The surface roughness of the second ring part is more than 12.5S.

A crack-containing shale stability evaluation device mainly comprises a kettle, a temperature control assembly connected with the kettle, a pressure assembly connected with the kettle, a back pressure control assembly, a gas source supply control assembly, a liquid medium assembly connected with the kettle, a core deformation measuring assembly connected with the kettle, and a data measuring and collecting assembly, wherein the kettle is used for fixing a core and simulating the environment around the core; the temperature control assembly is controlled to heat the core, control the temperature and simulate the actual temperature of a stratum; the pressure assembly is used for exerting confining pressure, required by experiments, on the core to simulate stratum burden pressure; the back pressure control assembly is used for back pressure control of the core; the gas source supply control assembly is used for providing a constant-pressure gas source on a core inlet end; the liquid medium assembly is used for providing clean water or slurry for the core and simulating the pressure action of drilling fluid circulation; the core deformation measuring assembly is used for measuring core deformation; the data measuring and collecting assembly is connected with the assemblies and used for obtaining expansion strain, the crack core pore pressure propagation rule and pressure penetration period monitoring results.

The invention relates to an ultrasonic tight oil imbibition experiment device comprising a rock fixed box; a fracture pipe capable of penetrating a tight coil rock penetrates one side of the rock fixed box in a sealed manner, and the other end of the fracture pipe is connected with a fracture liquid injection structure in a foldable manner; a push structure penetrates the fracture pipe in a sealedand slide manner, and provided with a plurality of ultrasonic probes; the side wall, on which the fracture pipe penetrates, of the rock fixed box is the first fixed box side wall; each side wall adjacent to the first fixed box side wall on the rock fixed box is provided with a telescopic potential resistance imbibition test structure; the ultrasonic tight oil imbibition experiment device also comprises a control portion; the control portion can control the work states of the fracture liquid injection structure, the push structure and the potential resistance imbibition test structure. The device can test oil-water replacement rate and oil extraction effects of fracture liquids of different formulas, can analyze the pressure propagation speed and oil-water replacement leading edge positionin the imbibition process, thus providing important meanings for selecting and optimizing and evaluating soak effects of fracture liquids of different formulas.

The invention relates to a strain gauge type pressure test tight oil inhibition experimental device, comprising a rock fixture structure and further comprising a control unit. The rock fixture structure can clamp rock containing tight oil and rotate around a horizontal shaft; a horizontal fracturing pipe runs from one side of the rock containing tight oil, one end of the fracturing pipe is connected with a fracturing fluid injection structure, and the fracturing pipe is provided with an inhibition cabin linkage sealing structure; the inhibition cabin linkage sealing structure is provided withmultiple resistance strain gauges; besides, a potential and resistance inhibition test structure is arranged above the rock fixture structure; the control unit can control working status of the fracturing fluid injection structure, the inhibition cabin linkage sealing structure and the potential and resistance inhibition test structure. The device can be used for testing oil and water displacement and oil production effect of fracturing fluid prepared based on different formulas, can analyze pressure propagation speed in inhibition process and oil and water displacement leading-edge position,and has a great significance in optimized evaluation on soaking effect of the fracturing fluid of different formulas.