Investigation of the dynamic loading of water-jet propulsion drive amphibious tracked vehicles

The article presents the results of theoretical and experimental investigations of the dynamic loading of water-jet propulsion drive of amphibious tracked vehicles. The relevance of the investigation is the need to increase the resource of drive elements. The purpose of the study is to study the reasons for the formation of a high dynamic loading of the drive. To achieve this goal, the following tasks are solved: 1 - the design scheme of the “engine - transmission - water-jet propulsion - machine” system is developed and simulation of the system dynamics is performed; 2 - the results of experimental research of the dynamic loading of water-jet propulsion drive during the movement of amphibious tracked vehicles afloat; 3 - aggregated results of theoretical and experimental investigations of convergence; 4 - specified algorithm for design calculation taking into account dynamic effects, arising in the water jets propulsion drive. In order to solve the set tasks, the system dynamics simulation was performed based on the developed mathematical model using the methods of theoretical mechanics, differential and integral calculus. The analysis of dynamic processes was carried out using the software LMS Imagine.Lab Amesim. Verification of the mathematical model and accepted assumptions was performed during the experimental investigation of the loading of water-jet propulsion drive of amphibious tracked vehicles. Methods of mathematical statistics, probability theory, and modal analysis were used for automated processing of experimental research results. Processing was performed in the Power Graph Professional application software. Analysis of the simulation results showed that the increased dynamic loading of the water jet propulsion drive occurs due to “beats” and resonances in the dynamic system when the stability of oscillatory processes is lost, leading to significant amplitudes of vibration acceleration. In this case, the effect of spontaneous loosening of bolted connections in a nonlinear system, described by I. I. Blechman, is manifested. The results of the investigation made it possible to Refine the design calculation algorithm and can be used in the design of water-jet propulsion drives of amphibious vehicles.