Vibration Analysis Of Fuel Tank System Of Mine Dump Truck Based On Fluid-solid Coupling

Mine dump truck belongs to off-highway dump truck.It refers to the dump truck which is mainly used to transport minerals and sand in the field of off-highway operation,such as large open pit coal mine,water conservancy and Hydropower projects.The fillet weld between the bracket of the fuel tank system and the longitudinal beam of the frame of a large mine dump truck manufactured by a company cracked after running in the mine for a period of time.This is related to the normal supply of fuel,and then affects the stable operation of mining dump trucks.The causes of cracking are studied and improvement measures are put forward.It is of practical significance to improve the design of mining dump truck.Considering that the cracking of the fuel tank system occurs after the mine dump truck has been running in the mine for a period of time,it is determined that the cracking is caused by fatigue.Fatigue is caused by alternating stress.When the dump truck is used in mine,the fuel tank is in vibration state,which will produce alternating stress.In order to study the fatigue problem of fuel tank system,it is necessary to analyze the inherent characteristics of fuel tank system,the maximum equivalent stress and its location,and the operating conditions when the maximum equivalent stress occurs.Firstly,the finite element analysis software ADINA is used to establish the models of fuel tank system with filling heights of 10%,30%,50%,70% and90% respectively.The inherent characteristics of five fuel tank systems with different filling heights are analyzed by potential fluid method in fluid-solid coupling.The results show that the same order modal frequency of fuel tank system decreases with the increase of filling heights and is similar to that of mine fuel tank system.The main reason for fatigue damage is random vibration under road excitation.Secondly,it is analyzed that the mine dump truck runs on grade C and D pavement at 20 km/h and 30 km/h respectively,and brakes on grade D pavement at 30 km/h and on grade D pavement at 18 km/h respectively.The maximum equivalent stress of five fuel tank systems with different filling heights under three limitconditions of D-grade pavement limit turning and braking on horizontal dry pavement at 18km/h per hour shows that the maximum equivalent stress of fuel tank system appears in the lower left part of the bracket,which is consistent with the actual cracking position.The maximum equivalent stress under various conditions is compared,and the maximum equivalent stress is extracted.Finite element fatigue analysis software MSC.fatigue is used to analyze the fatigue life of mining dump trucks.Finally,measures are put forward to improve the fatigue life by reducing the wall thickness of fuel tank to reduce the maximum equivalent stress of fuel tank system.By calculating,the maximum equivalent stress can be reduced by18.64%,and the fatigue life of fuel tank system can be increased by 22.18%.