237results about "Impulse engines" patented technology

The utility model relates to a nozzle device of an impulse turbine. The impulse turbine nozzle device comprises a spray pipe, an adjusting mechanism, a nozzle, a spray needle and a lining. The adjusting mechanism is installed in the spray pipe. The nozzle is of a conical hollow structure with two open ends. The large end of the nozzle is hermetically connected with one end of the spray pipe. And the end part of the large end of the spray needle is detachably connected with the end part of one end of the adjusting mechanism. And the spray needle is configured to integrally penetrate through the port of the small end of the nozzle. The lining is detachably installed in a port of the small end of the nozzle in a sealed mode and can make contact with the surface of the spray needle in a sealed mode. The bush is disposed so as to be entirely detachable from the small end side of the nozzle. According to the impulse turbine nozzle device, quick-wear parts such as the lining and the spray needle can be overhauled and replaced without disassembling the whole device, mounting and dismounting of the lining and the nozzle in an easy-wear power station are facilitated, the maintenance efficiency of the power station is greatly improved, and the economic benefit of the power station is improved.

The invention discloses a water turbine nozzle sealing structure and a manufacturing method thereof, and relates to the field of water turbine nozzle sealing, the water turbine nozzle sealing structure comprises a spray needle and a wear ring, the spray needle and the wear ring are provided with flow passing surfaces, a sealing surface exists in the flow passing surfaces, and the sealing surface of the spray needle and the sealing surface of the wear ring are attached to form hard sealing; the spray needle and the wear ring are respectively provided with a base body, a nitriding layer and a coating are sequentially arranged from the base bodies to an overflowing face, and the surface of the coating is the overflowing face. According to the sealing structure, it can be guaranteed that the overflowing faces of the spray needle and the wear ring are high in hardness and good in wear-resisting effect, meanwhile, the problem that the silt impact resistance and the cavitation resistance are insufficient is effectively solved, and therefore the service life of the sealing structure is prolonged.

The invention relates to the technical field of hydroelectric generation, in particular to an impulse turbine, a water bucket and a mortise and tenon joint structure for the water bucket and a hub. The water bucket comprises water bucket blades and tenons arranged at the roots of the blades; the shape of the tenon is configured to be movably assembled with a mortise formed in a hub of the water turbine in a fit clearance mode. According to the structure, a movable assembly mode with a fit clearance can be realized, and the water bucket can generate limited displacement in a gradual change clearance under different jet flow impact load conditions, so that the original traditional rigid connection is changed into flexible movable connection. The water bucket can be reliably connected with the hub without depending on welding or bolt fixing, and the common problem that in an original mode, a water head and a hub welding seam are prone to breakage under high-strength water impact force is solved.

The invention provides a design method for a water bucket notch of a multi-nozzle impulse turbine. According to the design method for the water bucket notch of the multi-nozzle impulse turbine, the problems of positioning and optimization of related sizes of the water bucket and the notch are fundamentally solved; the design accuracy and reliability are improved; the close combination of the design of the water bucket notch and the actual working water flow condition of the multi-nozzle impulse turbine is realized; it can be ensured that the interaction between the water bucket notch and water flow in actual operation reaches the optimal state, and energy loss or hydraulic performance reduction caused by unreasonable size is avoided; the shape of the water bucket notch and the shape of the water bucket can be optimally designed in a targeted mode, and the hydraulic efficiency of the multi-nozzle impulse turbine is further improved.

The invention relates to the technical field of hydroelectric generation, in particular to a method for determining distribution parameters of an impulse turbine, a water bucket and a pin column. The water bucket is of a double-bowl-shaped structure which is symmetrical along the water diversion blade, the water bucket is provided with an upstream face used for bearing water flow impact and a downstream face opposite to the upstream face, a plurality of pin columns are embedded in the downstream face in the normal direction of the downstream face, and the ends of the pin columns are matched with the surface of the upstream face to form a continuous smooth curved face of the upstream face. Under the conditions of high water head and sediment, deformation and cracking of the bucket and even damage of bucket breakage are avoided, and the service life of the bucket is prolonged.

The present application provides an impulse water turbine, an anti-erosion water bucket and an anti-erosion structure setting method. The water bucket has a double-bowl structure symmetrically along a water distribution edge. The water bucket has a water-impingement surface for bearing the impact of water flow and a backwater surface opposite to the water-impingement surface. The concave-convex points of the water-impingement surface are distributed in an array on both sides of the water distribution edge, the downstream area, the water outlet edge area and the water outlet area. The array of the concave-convex points on the inner surface of the water bucket can form a water film in the concave points under the impact of strong water flow. The water film generates a certain tension, thereby buffering the impact of the silt and protecting the inner surface of the water bucket. The anti-erosion performance of the water bucket of the impulse water turbine under the condition of high silt content can be greatly improved, and the problems of easy erosion, easy fracture and greatly shortened service life of the water bucket of the impulse water turbine under the conditions of high silt, high water head and strong impact force can be effectively solved.

The invention relates to a drainage device for a civil engineering tunnel, and belongs to the technical field of civil engineering drainage. The drainage device comprises a drainage box body, a water inlet pipe is arranged at the top of the drainage box body, a drainage pipe is arranged at the bottom of the side wall of the drainage box body, a filtering mechanism and a drainage mechanism are arranged in the drainage box body, the drainage mechanism is arranged at the drainage pipe, a collection box body is arranged on one side of the drainage box body, and the interior of the collection box body is communicated with the drainage box body. A collecting mechanism for collecting filtered matters is arranged in the filter chamber; the filtering mechanism comprises a first filtering plate obliquely arranged towards the collecting mechanism, a rotating paddle set rotationally installed on the drainage box body and a knocking assembly which is in transmission connection with the rotating paddle set and used for knocking the first filtering plate. Through reasonable design of the drainage device, the problem of water accumulation in the tunnel can be effectively solved, and slippery road surface and reduced visibility caused by water accumulation are avoided, so that the traffic capacity and safety of the road are improved.

The utility model discloses an assembly type impact rotating wheel, and belongs to the technical field of hydroelectric generating set devices. The structure comprises a wheel disc and a plurality of water buckets assembled on the circumference of the wheel disc, a concave groove is formed in the side wall of the circumference of the wheel disc, each water bucket comprises a bucket bucket and a bucket handle, the water buckets are assembled in the concave grooves through the bucket handles, and the bucket handles are positioned through a positioning mechanism and fixedly assembled on the wheel disc through a fixing structure; the water bucket is stable in structure, high in reliability and easy to implement, so that safe and stable operation of the whole unit is guaranteed, the stress condition of the root of the water bucket is optimized, the stress of the unit in the operation process is more uniform, meanwhile, the risks of flying and breaking of the water bucket are reduced through multiple guarantees, and safe and stable operation of the whole unit is guaranteed.

The invention belongs to the technical field of water turbine runners, and particularly relates to a bucket root configuration design method based on a negative Gaussian curved surface. According to the technical scheme, the bucket root configuration design method based on the negative Gaussian curved surface comprises the following steps that S1, a hydraulic design model is obtained and preliminarily analyzed; s2, rounding the part outside the high-stress area of the root in the step S1; s3, constructing a negative Gaussian curved surface of an unprocessed part in the step S2; s4, completing the structure and performing simulation calculation; and S5, according to the calculation result of the step S4, adjusting the parameters in the steps S2 and S3 until the parameters meet the requirements. According to the bucket root configuration design method based on the negative Gaussian curved surface, the root stress is reduced by constructing the negative Gaussian curved surface, the method does not depend on experience of users any more, meanwhile, mutual influence of parameters in different steps is reduced as much as possible, and the number of attempts of the users is reduced.

The invention relates to the technical field of clean energy power generation, in particular to a still water and mechanical wheel combined power generation system technology which is characterized in that a still water and mechanical wheel combined power generation system is composed of a water supply device, a frequency conversion speed control device, a mechanical wheel, a water energy tank, a water energy tank structure frame, an electromechanical device and a structure platform; according to the water supply device, a centrifugal pump is driven by a water pump motor, and still water in a water storage bin is lifted to a water energy tank to start a mechanical wheel. According to the speed control electric device, a high-speed speed control motor drives a multifunctional gearbox, the speed is converted to be smaller than 30 revolutions per minute, and then the mechanical wheel is controlled to rotate. The mechanical wheel comprises a water wheel shaft, a water wheel steel ring body, a water wheel steel ring body supporting frame and water wheel blades. The water wheel blades form a water containing included angle smaller than 75 degrees on the water wheel steel ring body. The water energy tank is an arc-shaped vertical water energy tank, the upper top end of the water energy tank is funnel-shaped, and the main body of the water energy tank is an arc-shaped tank; and the arc-shaped groove is matched with the joint section of the water wheel steel ring body in an arc shape.

A Pelton turbine comprising a rotor with a horizontal axis of rotation and a supply system with at least four nozzles which surround the rotor in a uniformly distributed manner in the circumferential direction, and wherein the supply system comprises a first arm (1) and a second arm (2), and wherein the first arm (1) is connected to at least two adjacent nozzles, and wherein the second arm (2) is connected to the remaining nozzles, and wherein each arm (1, 2) comprises a strand which partially wraps around the rotor, from which at least one first pipe branches off to a first nozzle, and wherein a further nozzle forms the end of the strand, and wherein each arm (1, 2) comprises a bend (1.1, 2.1) and a connecting pipe section (1.2, 2.2), and wherein the axes of the connecting pipe sections (1.2, 2.2) are aligned parallel to the axis of rotation of the rotor, and wherein each connecting pipe section (1.2, 2.2) is connected to the turbine via the associated bend (1.1, 2.1) is connected to the corresponding strand.

The utility model provides a water purification system which comprises a waterwheel, a water purification device and a generator, the waterwheel comprises a water containing barrel, a water wheel and a water scraping plate; the water containing barrel and the water scraping plate are installed on the water wheel, and the angle between the opening direction of the water containing barrel and the rotating direction of the water wheel ranges from 0 degree to 90 degrees. The water wheel is in transmission connection with the generator through a conveyor belt; the generator is electrically connected with the water purifying device; the water scraping plate bears the impact of an external water source to drive the water wheel to rotate; the water wheel drives the generator to generate electricity through the conveyor belt, so that the generator supplies power to the water purifier; the water containing barrel contains water supplied by an external water source and conveys the water to the water purifying device along with rotation of the water wheel. And the water containing barrel is mounted, so that more water can be contained in the rotating process of the water wheel, and then natural water flow can be taken out for use more conveniently. The water scraping plate is installed to drive the generator to generate electricity, so that the generator supplies power to the water purifying device, stable and reliable electric energy supply can be provided for a user, and energy conservation and environmental protection are achieved.

This invention relates to a waterwheel-type power generation device suitable for fast-flowing river environments with elevation differences. It concentrates the water flow from the rapid current into a channel, then utilizes the impact force of the water flow to drive a waterwheel. The waterwheel is connected to a permanent magnet generator via a speed increaser to generate electricity. This waterwheel-type power generation device includes a waterwheel, a generator, and a speed increaser. It also includes: a mounting base for installing the waterwheel, with a vibration damping and energy-capturing mechanism on the mounting base; a insertion mechanism on the mounting base for securely installing the mounting base on both sides of the channel; and a pressurization mechanism on the mounting base, which drives the insertion mechanism to continuously and stably fix the mounting base to one side of the channel. This waterwheel-type power generation device, suitable for fast-flowing river environments with elevation differences, ensures the installation stability of the waterwheel in complex fast-flowing environments and improves the equipment's service life and operating efficiency.

The invention discloses a mounting and measuring device for a water distribution ring pipe of an impulse turbine, which comprises a water wheel disc axis measuring part mounted on a water wheel disc shaft, the water wheel disc shaft is arranged at the axis position of a water wheel disc, and the mounting perpendicularity of the water wheel disc shaft can be detected through the water wheel disc axis measuring part. And a plurality of water spraying branch pipes for guiding water flow to impact the water wheel disc are arranged on the inner side of the water distribution ring pipe, and the water distribution ring pipe is arranged around the water wheel disc shaft. The device is designed according to existing requirements, a measurement basis can be provided for axis installation of the water wheel disc, the water wheel disc rotates more stably, light rays matched with a water flow path are provided on the branch pipe axis measurement component, and the light rays are detected through the light ray detection disc, so that the angle installation accuracy of the water spraying branch pipe is guaranteed; a measurement foundation is provided for water turbine accessory installation, and the installation accuracy is guaranteed.

Pelton-type wheel with buckets and heels mechanically assembled to a hub, and associated embodiment. The invention relates to a Pelton-type wheel (1) with a central axis (X) and comprising: - a hub (2); - a plurality of one-piece parts (3), each consisting of at least one bucket (30) extended by a heel (31) at one of its longitudinal ends and distributed around the periphery of the hub, with each heel bearing radially against a peripheral edge of the hub; - at least one clamping flange (4), bearing against at least one of the principal faces (21) of the hub and at least one of the lateral edges of the bucket heels; - a plurality of clamping screws (5), screwed into the hub, laterally clamping the flange against said at least one principal face of the hub and said at least one of the lateral edges of the bucket heels. Figure for the abstract: Fig. 1

A turbine that includes a runner and a variable nozzle. The runner is configured to rotate about an axis of rotation. The variable nozzle is configured to produce a sheet flow when fluid passes through the variable nozzle toward the runner. The sheet flow has a circumferential length at an exit of the variable nozzle that is greater than a flow width at the exit of the variable nozzle. The flow width is adjustable. In other configurations, the sheet flow may be planar, conical, or cylindrical.

The utility model relates to be provided with main and auxiliary water car's horizontal flow water power generation system, including main water car and auxiliary water car, the main water car is equipped with main water car axle, the auxiliary water car is equipped with auxiliary water car axle, and the coaxial opposite setting of main water car axle and auxiliary water car axle is connected through the clutch type shaft coupling, and the shaft coupling device of main water car axle and the shaft coupling device of auxiliary water car axle are cylindrical, and are respectively covered in the opposite end of main water car axle and auxiliary water car axle, and the shaft coupling device of auxiliary water car axle is axially sliding fit with auxiliary water car axle and is circumferentially opposite fixed, the spring for pushing the shaft coupling device of auxiliary water car axle to the shaft coupling device of main water car axle is covered on auxiliary water car axle, and the opposite end surface of the shaft coupling device of main water car axle and the shaft coupling device of auxiliary water car axle is equipped with the meshing structure for realizing positive engagement reverse separation, can be according to operation demand, and automatically realizes the separation and combination of main and auxiliary water car axle, guarantees the power generation efficiency of power generation system and is convenient for maintenance and maintenance.

The invention discloses a rainwater power collection and utilization system, and relates to the technical field of rainwater collection equipment. The device comprises blades, a stand column, a shielding area and a power collection center shaft, a fourth quadrant area formed by rotation of the blades is set as the shielding area, and the shielding area is erected and fixed through the stand column; the blades are composed of folding pieces, a center column and turning hinges, the power collection center shaft is connected with the multiple blades, the blades are fixedly connected with the power collection center shaft through the column end of the center column, the folding pieces are connected to the two side edges of the center column through the turning hinges, a foldable folding piece structure is formed, the folding pieces are in a dustpan-shaped concave shape, and the folding pieces are connected with the power collection center shaft through the turning hinges. And a water storage groove is formed. The device can collect rainwater descending potential energy, generates electricity and does work through rainfall potential energy, reduces the electricity generation cost, benefits people, and is wide in application prospect.

The invention relates to a system device for lifting seawater power generation and aquaculture water by using sea wave impact force. The device comprises a seawater lifting system, a seawater storage system, an aquaculture system and a power generation system, sea waves are collected through the horn mouth, meanwhile, the characteristic that the impact force pressure intensity of the sea waves is large is utilized, the seawater position is lifted through the shrunk pipeline, and seawater enters the water storage pool. And low-water-level water in the reservoir is introduced into the culture pond for daily use according to use requirements. And the high-water-level seawater in the reservoir generates electricity through the impeller generator. The electric power used by the breeding plant is from the power generation of the system, so that the breeding cost is not additionally increased. Meanwhile, unused electric power can be accessed to a power grid to generate benefits.

A hydropower recycle system, relating to the technical field of hydroelectric power generation, includes a turbine device, a power generating device and a rooftop water tank (2). The turbine device and the power generating device are provided at the top of the rooftop water tank (2). A water inlet (21) is provided at the top of the rooftop water tank (2). The turbine device includes a turbine housing (3), a turbine (5), a high-pressure nozzle (6) and a turbine rotating shaft (4). The turbine housing (3) is provided above the water inlet (21). A water outlet is provided at the bottom of the turbine housing (3). The turbine (5) is provided inside the turbine housing (3). The turbine rotating shaft (4) passes through the turbine housing (3). Apart of the turbine rotating shaft (4) located in the turbine housing (3) is connected to the turbine (5), and one end of the turbine rotating shaft (4) extending out of the turbine housing (3) is transmittingly connected to an input shaft of the power generating device. The high-pressure nozzle (6) is fixedly disposed on a sidewall of the turbine housing (3). The hydropower recycle system has the advantages of small commitment resources, short installation and debugging time, and slight influence on the environment. The energy which is originally necessary to be used is recycled, the recycled energy is supplied to the buildings for use or is sold to the power grid, thereby providing green energy and reducing carbon emission.

The present invention includes an apparatus for harnessing the kinetic energy of ocean currents, seas, or estuaries by transferring the kinetic energy of the water to a turbine that drives a generator. The apparatus consists of several parts, mainly including: A) an ejector pump with an intake and a mixing chamber, and B) a cross-flow turbine M1 (revolving door type, two blades).

A bucket of a Pelton turbine with an outlet edge curved at least in segments. To achieve a particularly high efficiency, it is provided according to the invention that the outlet edge forms a rear hump in a side view, wherein a center of curvature of the hump is positioned below the outlet edge in a side view and a peak of the hump is located closer to the cup base than to the bucket face.

The invention discloses an impulse turbine capable of generating power bidirectionally, and relates to the technical field of water turbine.The impulse turbine comprises a water turbine main shaft, a rotating wheel disc and an annular water conveying pipe, the water turbine main shaft is fixedly inserted into the rotating wheel disc, and a plurality of connecting rods are arranged on the outer wall of the rotating wheel disc along the circumference; one end of the connecting rod is inserted into the rotating wheel disc and is fixedly provided with a gear, and the other end of the connecting rod is fixedly provided with a steerable water bucket. When the water turbine needs to be braked or steered, the steering system can be put into use, other equipment does not need to be disassembled or added, and therefore the device is more convenient to use; when the water turbine is shut down or load shedding occurs due to accidents, the steerable water bucket and the steerable nozzle are controlled by hydraulic control equipment to conduct steering operation, and meanwhile, a water inlet valve on the water spraying pipe is opened, so that water flow reversely impacts the steerable water bucket through the steerable nozzle, and then braking torque opposite to the original rotating direction is provided; therefore, rapid braking of the impulse turbine is achieved.

The present application relates to the technical field of heating, and discloses a heating system, comprising an outdoor heat exchange device and an indoor heat exchange device. The outdoor heat exchange device comprises a plate heat exchanger; the indoor heat exchange device comprises a housing, a heat exchange tube, heat exchange fans, and a storage battery; the heat exchange tube, the heat exchange fans, and the storage battery are all mounted in the housing; the storage battery is electrically connected to the heat exchange fans and supplies power to the heat exchange fans; a first circulation pipeline is communicated between a liquid outlet of the heat exchange tube and a cold side inlet of the plate heat exchanger; a water pump used for conveying water in the heat exchange tube to the plate heat exchanger is connected in series on the first circulation pipeline; a second circulation pipeline is communicated between a cold side outlet of the plate heat exchanger and a liquid inlet of the heat exchange tube; a turbine generator is connected in series on the second circulation pipeline; and the turbine generator is electrically connected to the storage battery, and the generated electricity is stored in the storage battery. The present application has the effects of reducing the need for indoor wiring and power strips, and shortening the construction period of the heating system.

The utility model discloses a rainwater power collection and utilization system, and relates to the technical field of rainwater collection equipment. The device comprises blades, a stand column, a shielding area and a power collection center shaft, a fourth quadrant area formed by rotation of the blades is set as the shielding area, and the shielding area is erected and fixed through the stand column; the blades are composed of folding pieces, a center column and turning hinges, the power collection center shaft is connected with the multiple blades, the blades are fixedly connected with the power collection center shaft through the column end of the center column, the folding pieces are connected to the two side edges of the center column through the turning hinges, a foldable folding piece structure is formed, the folding pieces are in a dustpan-shaped concave shape, and the folding pieces are connected with the power collection center shaft through the turning hinges. And a water storage groove is formed. The utility model discloses can collect the potential energy of rainwater decline, utilize the rainfall potential energy to generate electricity and do work, reduce the electricity generation cost, benefit public, application prospect is wide.

The invention belongs to the technical field of fluid power generation, and particularly relates to a buoyancy self-adaptive vibration energy storage system based on closed mine shaft water recharge, which comprises a plurality of guide rails fixedly arranged on the inner side wall of a mine, the guide rails are parallel to the axis of the mine, and the plurality of guide rails are arranged at equal intervals along the circumferential direction of the inner side wall of the mine; the connecting assembly is slidably connected with the guide rail; the energy storage power generation assembly is fixedly arranged at the top end of the connecting assembly, and the energy storage power generation assembly is used for converting impact potential energy of recharge water entering the mine into elastic potential energy and converting the elastic potential energy into electric energy; the buoyancy assembly is fixedly arranged at the bottom end of the connecting assembly and used for providing buoyancy for the connecting assembly and the energy storage power generation assembly; the limiting assembly is arranged at the top end of the guide rail and used for preventing the buoyancy assembly from driving the energy storage power generation assembly to float out of the mine wellhead. The device can automatically adapt to water level changes and efficiently capture vertical water flow kinetic energy.

The invention discloses a closed type hydroelectric power generation system, and relates to the technical field of hydroelectric power generation. A closed type hydroelectric power generation system comprises a plurality of sets of power generation devices, a first water storage tank, a hydraulic ram, an axial flow pump and a second water storage tank, the multiple sets of power generation devices are arranged in the hydroelectric power generation system and connected through pipelines, the tail ends of the sets of power generation devices are connected with the first water storage tank through pipelines, and the water storage tank is connected with the water storage tank through pipelines. The reservoir I is connected with the hydraulic ram and the axial flow pump through pipelines, the hydraulic ram is connected to the starting end of the complete power generation device through a pipeline, and the axial flow pump is connected with the reservoir II through a pipeline. Water flow is pressurized through the hydraulic ram and then conveyed to the starting end of the complete set of power generation device to form circulating power, the axial flow pump conveys redundant water to the second water storage pool to be stored and adjusted, efficient utilization of water resources and continuous power generation are achieved, and good environmental adaptability and popularization value are achieved.

The invention discloses a lever effect V-blade type semilunar horizontal water turbine, and belongs to the field of hydroelectric generation. Comprising a half-moon-shaped shell, a base tail water tank, a V-blade type lever rotating wheel, a nozzle, a power generation ball and a main shaft, and the V-blade type lever rotating wheel comprises a rotating wheel disc with a lever effect and a plurality of V-shaped blades. Compared with the prior art, the shape of the half-moon-shaped shell is matched with the rotating wheel disc, the half-moon-shaped shell is used for installing the nozzle, the distance between the nozzle and the rotating wheel disc can be shortened, and water flow loss of the nozzle is reduced; the V-shaped blade is provided with a V-shaped opening, so that water flow sprayed by the nozzle can be received, the utilization rate of the water flow can be improved, airflow friction resistance generated in high-speed rotation can be reduced by utilizing the V-shaped tip, and therefore, energy loss can be reduced, and the energy utilization rate can be improved; when the V-shaped blades rotate to the bottom of the rotating wheel disc, water can be discharged, the load bearing of the rotating wheel disc is reduced, the rotating wheel disc has the lever effect, and the power generation efficiency of the water turbine can be improved.

The utility model relates to a self-power-generation anti-blocking sewer well lid which comprises a first box body, a second box body, a support assembly, a frame assembly and a water wheel device. The first box body is movably connected with a plurality of controllable closed lotus leaf pieces, and the lower end face of the first box body is connected with the support assembly and used for supporting the controllable closed lotus leaf pieces; the lower end of the first box body is connected with the frame assembly, and the frame assembly is connected into the second box body. The water wheel device is connected to the frame assembly. Preferably, the support assembly comprises a plurality of rolling rotation limiting blocks, two second limiting blocks, two S-shaped connecting pieces, a first optical axis and a second optical axis. The utility model aims to provide the self-generating anti-blocking sewer well lid for overcoming the existing defects, and mechanical energy brought by accumulated water can be converted into electric energy.

The invention relates to a blade (2) of a Pelton turbine with a trailing edge (6) that is curved at least in sections. According to the invention, in order to achieve particularly high efficiency, the trailing edge (6) forms a rear hump (7) from a side view, wherein, from a side view, a centre of curvature of the hump is positioned below the trailing edge (6) and a vertex (10) of the hump is located closer to the cup root (3) than to the blade end (4).