7results about How to "Good fluid performance" patented technology

The utility model discloses a propelling device and an underwater robot, and relates to the technical field of underwater driving equipment, the propelling device comprises two propellers integrated in two cavities of a support, in a standing state, when any propeller is a horizontal propeller, the other propeller is a vector propeller; therefore, the propelling device can have thrust in a single direction, the generated thrust vectors can be combined, the maneuverability, the stability and the operation flexibility of the underwater robot can be enhanced, and the propelling device is suitable for various complex underwater application scenes.

The invention provides a hair drier, and relates to the technical field of household appliances. A blower includes a flow channel housing, a motor, and an impeller. The runner shell comprises a shell body, a motor base and a plurality of flow deflectors. The shell is provided with a cavity, an air inlet and an air outlet, the motor base is arranged in the cavity, and a flow channel is formed between the outer periphery of the motor base and the inner wall of the shell. All the flow deflectors are arranged in the flow channel at intervals in the circumferential direction of the motor base, one side of each flow deflector is connected with the motor base, the other side of each flow deflector is connected with the shell, and a fluid channel is formed in the interval between any two adjacent flow deflectors. The motor is installed on the motor base, and the impeller is installed on an output shaft of the motor and located at one end of the motor base. The ends, close to the impeller, of the flow deflectors are bent corresponding to the rotating direction of the impeller. According to the blower, the problem of large on-way loss of airflow can be solved, so that the hydrodynamic performance of the blower is improved.

The invention discloses a preparation method of a concrete mixture water molecule migration inhibitor. The preparation method comprises the following steps: (1) mixing sephadex and xanthan gum, weighing the mixture, adding the mixture into an aqueous solution of phosphate, and stirring until the mixture is completely dissolved to form a water-retaining solution; (2) weighing a water-retaining solution, putting the water-retaining solution into a stirring device, increasing the rotating speed to be not less than 6000 r / min, slowly adding the modified sodium alginate microspheres, uniformly stirring, extracting the modified sodium alginate microspheres from the stirring device, and standing until the solution is stable to form a concrete mixture water molecule migration inhibitor; the modified sodium alginate microspheres take magnesium hydroxide as a porous structure, and pores are filled with sodium alginate and magnesium sulfate. By adopting the inhibitor, approximate laminar motion is controlled in the early stage of mixture coagulation, diffusion motion is controlled in the later stage of coagulation, internal free water is effectively controlled to excessively migrate to the surface, and adverse effects of migration of water molecules on concrete strength and apparent quality are avoided.

A multi-objective optimization method for a two-dimensional pump damping groove based on a GA-BP neural network includes the following steps: S1, establishing design variable parameters in the two-dimensional pump damping groove structure; S2, constructing a simulation model of a two-dimensional piston pump and using this model to simulate and obtain the performance parameters of the hydraulic pump; S3, constructing a GA-BP surrogate model, the process of which is as follows: S31, generating a sample dataset with good parameter space filling performance using Latin hypersquare sampling based on the design variable parameters; S32, establishing a BP neural network model and using a genetic algorithm to optimize and train the model based on the sample dataset, finally obtaining a BP neural network model optimized by the genetic algorithm; S4, using the GA-BP neural network surrogate model as the fitness function, performing multi-objective optimization of the damping groove structure parameter space using a fast non-dominated sorting genetic algorithm to obtain the optimal parameter solution set. This invention significantly improves the comprehensive fluid performance of two-dimensional pumps.

The invention discloses an acid-soluble cement slurry plugging agent for oil wells and a preparation method thereof, and belongs to the technical field of plugging agents. The acid-soluble cement slurry plugging agent for oil wells comprises the following components in parts by weight: 55-80 parts of G-grade oil well cement, 5-30 parts of calcium carbonate powder, 5-25 parts of lime powder, 5-15 parts of bentonite powder, 5-10 parts of modified acid-soluble gel, 5-10 parts of modified tricalcium phosphate, 5-10 parts of fluid loss reducer and 1-5 parts of accelerator. The preparation method of the acid-soluble cement slurry plugging agent for oil wells of the present invention comprises: mixing G-grade oil well cement, bentonite powder, lime powder, calcium carbonate powder, modified acid-soluble gel, modified tricalcium phosphate, fluid loss reducer and accelerator in two steps to obtain the acid-soluble cement slurry plugging agent for oil wells. The present invention significantly improves the compressive strength and acid dissolution effect of the acid-soluble cement slurry plugging agent for oil wells.

The utility model discloses a kind of PCB motor and its micro fan based on LDS, and PCB motor based on LDS includes LDS base and PCB coil board, and the surface of LDS base is equipped with the metal circuit formed by LDS technology. Reasonably replace the way of winding stator coil of traditional enameled copper wire with PCB coil board, i. e. directly printing stator coil on PCB board, can greatly reduce the volume and occupied space of stator coil, and PCB coil board is directly welded on LDS base, further simplifies structure, reduces the number of components. Integrate the overall structure of micro fan into PCB motor based on LDS, utilize the wiring flexibility of LDS base, effectively optimize overall structure layout, without occupying fluid space inside micro fan, make micro fan more compact and light. In addition, external or built-in drive circuit module structure design can also be selected, to meet different use requirements.

The utility model discloses a torsion type pipeline water turbine damping grid position adjusting mechanism which comprises a conveying pipeline, a sliding groove module and a movable damping grid. A guide through groove is formed in the conveying pipeline and extends in the conveying direction of the conveying pipeline. The sliding groove module is arranged outside the conveying pipeline, the interior of the sliding groove module is communicated with the guide through groove, a variable-pitch spring is arranged in the sliding groove module, and the telescopic direction of the variable-pitch spring is consistent with the extending arrangement direction of the guide through groove; the movable damping screen is arranged in the conveying pipeline in a sliding mode and provided with a connecting rod and a sliding block. One end of the connecting rod penetrates through the guide through groove and then is connected with a sliding block; the sliding block is fixedly connected with one end of a variable pitch spring; when the movable damping screen is scoured by fluid, the variable-pitch spring provides resistance for the movable damping screen so that the movable damping screen can move to the stress balance position. After the scheme is adopted, the self-adaptive adjustment of the position of the rectifying grid can be realized.