Simulation Of Logging-while-drilling Tool Response Using Integral Equation Fast Fourier Transform

With the development of society, oil has became the main raw material of modern industry. There are many reasons that the new energy replaced the oil have not produced. Therefore, thestudy about the logging technology has great economic value. The simulation of logging-while-drilling tool response is important for optimization design of new instruments, data processing and logging interpretation. In the tradition, the numerical simulation of electrical logging is based on the certain formation model. With the characteristic of axial symmetry of the target areas, we can simplify the problem of solving as a two-dimensional problem and easy to compute the result. But with the development of the middle and later period of the oilfields, some complex formation, such as thin inter-beds and dip formation, become more common. So the study of the numerical simulation for 3-D inhomogeneous formation model has became more and more important. The paper is carried out in this background with four topic in the contents:First, this paper discussed the working principle of the radio wave propagation logging and induction logging in detail.The research of this paper carried out on the background of one transmit coil and two receive coil of the radio wave propagation logging. Then, we simulate the response of the logging using the MoM.Second, we discussed the method of IE-FFT. And we study and analysis the stencil of the interpolation of Green’s function.Third, relying on the program of the simulation with the fast algorithm of IE-FFT, we do some research about the model and gives some advice with wide applicability. The numerical results proved the effective of the simulation of LWD tool of response with the fast algorithm of IE-FFT. By compared with the other methods, it clears that the IE-FFT method has its own superiorityin the aspect of the memory requirement and CPU time. So we successfully simulated the large scale well with multi-layer model. And then do some research about parameters of logging problems. We study the characteristics of the well logging model. We derived the electromagnetic field produced by the horizontal component of the transmitting coil, and then study the detection capability for the formation boundary using dip transmit coil.Last, we try to do some research about the problem of large contrast in integral equation. This paper proposed two method, the segmentation processing and the processing of segmentation with updates the background of Green’s function, which have good effect for improving the convergence speed. But all those can’t sufficient, so we put forward some own ideas about large contrast problem.All the research in this paper is about the radio wave propagation logging, so this paper can be reference for the study of the low frequency electromagnetic sounding.