Downhole Sound Radiator for Enhancing Oil Recovery

XU Aiqun^{1, 2}  XIANG Zhanqin¹  CHEN Zichen¹

(1. Institute of Modern Manufacturing Engineering, Zhejiang University, Hangzhou 310027;
2. Department of Mechanical Engineering, Jiaxing College, Jiaxing 314001)

Abstract: Based on the analysis of the physical model of oil well and the rule of sound wave propagation in oil reservoir, conditions for realizing total transmission of sound wave in oil well are deduced, which are used to determine the resonance frequency of sound radiator. Based on the radial size of oil well and the features of oil field distribution, the shell structure of low-frequency and flex-ional sound radiator is designed. Vibration equation of sound radiator with analogous spherical shell is deduced on the basis of Hamilton’s principle. Kinetic parameter equations of sound radiator are deduced, which include normal displacement, tangent displacement, bending moment, amplitude ratio, and resonance frequency. Equation of sound source level and drive force is set up in terms of the relationship between sound radiator volume displacement and sound power. As the result of the experiment about excitation current vs drive force, the actuator can provide sufficient power for sound radiator, therefore, the way of developing small-volume low-frequency high-power sound radiator is feasible.

Key words: Sound radiator  Shell  Dynamic equation  Sound transmission

CLC No: TB532 TE934

Received 200770520, received in revised form 20071209

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