Design Of Sediment Removal Device Beneath The Deep Sea And The Research Of Working Mechanics

With the rapid development of aviation industry in modern society,there are more and more air crash occurring in deep sea.Black box is an important recording instrument.Since the MH370 accident in 2014,more and more people in the world began to pay attention to black box’s search and salvage operation.The sedimentation of the sediment is very serious in deep sea,so the black box is usually covered with a thick layer of seabed sediments which is seriously affecting the search and salvage operations of black box.The main goal of this paper is to design an engineering prototype which can finish the operation of sediment removal in 6000 meter deep sea,and study the working characteristic of sediment removal by the way of experiment.The theoretical study of this paper is based on Rajaratnam’s theoretical and experimental study.A new mathematical model is constructed by adding an important parameter called impinging angle.In combination with the experiment data and with the use of the curve fitting method,the functional relationship among the impinging distance and angle,as well as the coefficient C4 are obtained.An experimental device to study the working characteristic of sediment removal by submerged water jet is designed and built.A serious of experiments has been carried out in different impinging angles and impinging distances.A new method of measurement is using called "cut copy and contour" which is used to measure the scour hole.Then analyzed the variation curve of scour hole shape with the impinging distance and impinging angle.the influence of impinging distance and impinging angle to sediment removal’s characteristic has been studied.In combination with the variation curve,we can obtain the well range of impinging distance and the well range of impinging angle.According to the design requirement of deep sea sediment removal device,the sediment removal device and experimental device is designed and built.A serious of experiments has been carried out to check the feasibility of the sediment removal device.The experimental data shows that sediment removal device by submerged water jet can meet the index of the project in the best range of impinging distance and impinging angle.And the way of repeated sediment removal is better than that of forward sediment removal.