Study On The Structure Of Jet Hole For Shark Gills Based On Artificial Muscle

Focusing on the issue that it is difficult to achieve the best effect of drag reduction problem for the biomimetic jet surface drag reduction technology in the changes in the mainstream of the velocity field,a kind of bionic gills structure,which can realize the adjustment of jet flow,was designed,and it also behaved a great significance for the theory of surface drag reduction of biomimetic jet which applied in the practical engineering.Based on the national natural science fund: Research on characteristics and mechanism of bionic jet drag reduction(51275102),a bionic gills structure was developed through the analysis of the shark gills jet characteristic,and it also can realize the adjustment for function of the jet flow.The posture characteristics of shark head out branchial cleft part was studied,and the size parameters of its head and gills was also obtained.Furthermore,in terms of experimental study,the jet hole structure and the principle of adjusting the parameters of the jet flow were gained,and the movement control law of the shark gills musculoskeletal structure was presented.Based on the flexible driving of IPMC artificial muscle material,the overall design scheme of bionic gill unit was put forward.Also,theory model of the adjustment of jet flow was established.According to force analysis of the bionic gill plate in the flow field,the fluid dynamics theory model was further developed.Using the Lagrange method,the dynamic model of bionic gill oscillation system was proposed.The paper proposed a method of creating IPMC linear driving unit simulation model which uses a flexible connecting piece based on bushing,and verified the accuracy of this method;Using CFD calculation method,this paper studied the stress of the gill plate in different swing angle and different flow velocity,and fitted the gill plate's Function of two variables between the dynamic pressure and both with the three interpolation method based on three angle;After the simulation analysis,the paper obtained the control laws of both the IPMC linear driving unit motion and the jet flow regulating,and verified the rationality of mechanism design and studied the deformation problem of large deflection under pressure in use of the bionic gill plate made by rubber sheet,and obtained the approximate solution of correction between the theoretical value and the true value under the comparison of jet flow parameters with the condition of rigid gill plate.The paper studied the 3D print processing methods on the key parts,and manufactured the skeletal system of bionic gill unit using the three-dimensional technology;checked the strength and rigidity of branchial arch's main stress parts considering the deterioration of ABS plastic's mechanical properties after twice forming,proving the mechanical design firm that can fit the use requirements;besides,this paper finished machining and assembling of the bionic gill unit,and verified the feasibility and rationality of mechanism design by experiment.