Analysis Of Low-frequency Petrophysical Instruments And Numerical Experiments Of Stress-strain

With the development of the seismic interpretation refinement,higher requirements have been put forward for the accuracy of petrophysical parameters.The cross-band petrophysical parameter measurement system can obtain the petrophysical parameters of the ultrasonic bandwidth and the seismic bandwidth.To systematically study the relationship between rock physical properties and elastic parameters in different bandwidth,especially the seismic bandwidth,the propagation law of seismic waves provides strong support.The emergence of low-frequency petrophysical measurement systems has made up for the data gaps to a certain extent.However,the data measured during the actual experiment always shows the magnitude of several anomalies,and the magnitude of these anomalies is unlikely to reflect the true rock parameters,which will result in unreliable measurement data.To analyze the reasons of these abnormal amplitudes and quantify them,a numerical simulation model is established for rock physics experimental equipment based on stress-strain relationship,which is jointly developed by China University of Petroleum(Beijing)and Curtin University in this paper.The finite element method is used to improve the measurement system based on the original model,and the natural frequency and frequency domain modal analysis are performed on the numerical model to analyze the causes and influencing factors of the abnormal amplitude.Compared with the actual experiment,the simulation experiment is carried out on the numerical model.The parameters obtained by numerical experiments are used to calculate the Young's modulus and Poisson's ratio of the simulated sample and compared with the standard value to analyze the error ratio,which will have a positive guiding effect on the actual experiment.