Study On The Swaying Dynamics Of Amphibious Artillery In Numerical Wave Pools

Numerical wave tank is a numerical test for the interaction of waves and ocean floating structures,which is widely used in the field of naval architecture and marine engineering.Amphibious artillery floating on the water crossing process,such as wind,wave and current disturbed,it will sway waterborne performance six degrees of freedom.Amphibious artillery motions will adversely affect and the firing accuracy.Therefore,employ numerical wave tank technology study the amphibious artillery swing capacity is very necessary.This paper takes amphibious self propelled artillery as an example to study the numerical simulation of amphibious weapons on water performance.A numerical wave tank is established to verify the wave effect and wave attenuation effect of the first order linear wave and two order Stokes wave,and the coupling area between the wave and the amphibious self propelled artillery in the numerical wave tank is obtained.The amphibious self propelled artillery towing model test was carried out in a test tank.The coefficients of the nonlinear rolling equation were obtained through the free decay curve by Hilbert transform method and GZ curve,and the nonlinear rolling equation of amphibious gun was determined.Fluent was extend the function by second development technology of UDF about the two-dimensional cross section of amphibious self propelled artillery rolling motion based on the amphibious self propelled artillery at different initial angle of the free roll decay curve,and shake free cross comparison attenuation curve of towing test,simulation of the average rolling period is T_m=2.896s,the test rolling period is T_s=2.998s,the relative error is 3.52%;Effect of different wavelength,wave height,amphibious self-propelled artillery rolling,swaying,heaving and pitching motion response,surge and heave motions are studied by using fluid-structure interaction method,and the the changes of morphology,wave and amphibious self-propelled artillery of the interaction of dynamic pressure and dynamic response are obtained.When the amphibious self propelled artillery is rolling,swaying and heave,the motion response increases with the increase of wave height under certain wavelength.Under certain wave height,rolling and heave motion increases with wavelength increasing,but wavelength has little effect on the motion of the amphibious cannon.When the amphibious artillery is pitching,sway and heave,the pitch and heave motion increases with the increase of wavelength and wave height,and the longitudinal motion decreases with the increase of wavelength and wave height.The results show that:the simulation results are in good agreement with the experimental results.The related conclusions can be used for reference in the development of amphibious artillery.