Design Of Rock Fatigue Experiment Based On Ultrasonic Transducer

In recent years,with the development of ultrasonic transducer,the technology of acoustic drill developed by ultrasonic transducer is more and more mature,and the products applied to science and life are increasing.The research on the working principle,vibration characteristics,output characteristics and vibration sinking performance of acoustic drill has become mature.The laboratory has designed and modeled the sonic drill,completed its dynamic analysis and drill pipe fatigue analysis,and verified the influence of connection mode on its drilling performance,but the interpretation of rock fragmentation mechanism needs to be improved.Under this research background,this paper designs a fatigue test device on the basis of the existing acoustic drill in the laboratory from the way of breaking rock by acoustic drill.Through the test,we can determine whether the fracture belongs to mechanical impact fracture or fatigue fracture,and then lay a certain foundation for the interpretation of rock fragmentation mechanism.The main contents are as follows:(1)According to the working principle of acoustic drill and ultrasonic vibration fatigue test,the structural size of the sample and the length of the base are designed and calculated,the material selection and optimization are carried out,and the natural frequency is 23612 by ANSYS simulation And the natural frequency of the ultrasonic transducer is the same as that of the ultrasonic transducer in the laboratory,and the harmonic response analysis of the whole fatigue test system is carried out.The resonance mode of the fatigue test system is solved,which can meet the requirements of maximum stress and zero displacement at the cross section of the specimen,so as to accelerate the stress cycle of the ultrasonic fatigue test system.(2)The preliminary design of different stress adjustment schemes is carried out.For different rock samples and different sizes of rock samples of the same material,it is necessary to adjust the whole device to achieve different stress values,so as to achieve different cycle times,so as to make the test data more reliable,and the curve drawn can clearly explain the way of rock fragmentation.The above research provides a theoretical basis for the application of ultrasonic transducer in ultrasonic fatigue test and lays a foundation for the interpretation of rock fragmentation mechanism.