3results about How to "Improve drag reduction efficiency" patented technology

The invention discloses tough anti-fatigue hydrogel for buffering impact and a preparation method, and belongs to the field of novel soft materials. Based on the energy internal consumption design combining a long-chain linear polymer preparation strategy and a solvent space limitation strategy, the long-chain high-polymer hydrogel without cross-linking points is prepared by increasing the content of an acrylamide monomer in a precursor solution and utilizing the strong water binding capacity of hydrophilic salt calcium chloride. The prepared hydrogel is linear hydrogel with tough and anti-fatigue characteristics, chains in the linear hydrogel are more easily entangled, the linear hydrogel has higher interaction between the chains, the fracture toughness, the fatigue threshold and the energy absorption of the hydrogel can be effectively improved, and the hydrogel can be widely applied as a high-performance damping material.

The utility model discloses a deformable surface resistance reduction device based on bionic tegillarca granosa. The device comprises a deformable plate body structure module, the deformable plate body structure module comprises a main plate and a plurality of adjustable structures arranged on the main plate, and the adjustable structures are used for forming a dynamically adjustable resistance reduction surface; and the driving adjusting mechanism module is used for controlling the form of the adjustable structure so as to dynamically adjust the surface flow field characteristics of the deformable plate body structure module, and the real-time variable drag reduction effect is achieved. By simulating the concave-convex shape of the surface of the scapharca granosa shell, dynamic switching between a smooth surface and a groove surface is achieved through unfolding and folding of the corrugated plates, the surface shape can be adjusted in real time according to fluid parameters, and compared with a traditional fixing structure, the drag reduction efficiency is improved.

This application provides a polymer brush, its preparation method, and its application in fluid drag reduction. The preparation method includes: preparation of an initiator layer; preparation of a PNIPAM brush: under a nitrogen atmosphere, N-isopropylacrylamide, pentamethyldiethylenetriamine, and acrylic acid are added to a mixed solvent of methanol and deionized water, and then cuprous bromide is added to obtain a polymerization reaction solution. A substrate material coated with an initiator layer is immersed in the polymerization reaction solution to perform a SI-ATRP reaction, and a PNIPAM brush is obtained on the surface of the substrate material. Preparation of a DM-PNIPAM brush: 4-dimethylaminobutamine and an activator are dissolved in N,N-dimethylformamide to obtain a modified solvent. The substrate material grafted with the PNIPAM brush is immersed in the modified solvent and reacted to obtain the polymer brush, i.e., the DM-PNIPAM brush. The polymer brush provided by this application improves its stability and durability as a drag-reducing agent in fluid drag reduction.