Experimental Studies On Damage-Relieving Depth By Ultrasonic Stimulations

Reservoir types of china is numerous and complicated, adopting the various technology and measure of increase the production in exploiting process leads to various contradiction be outstanding gradually, and the oil layer accepts all kinds of hurting, which makes more and more difficult to develop the oil field. Ultrasound has brought hope to the reservoir development because this method needs less money, does not do any hurts to reservoir and effect solves hurts in damage relieving. The mechanics, affecting factors and the range of damage relieving of ultrasound is preliminary discussed in the paper. And, throng literature research, the range of damage relieving using ultrasound is discussed. The test initially studies the ultrasonic attenuation of water in the flat-slab model and long-tube model, sand in the flat-slab model and long-tube model and artificial core, this test is done under different ultrasonic conditions. It is found that in various models the attenuation coefficient of ultrasound in water increases when the distance is increased, and the attenuation coefficient is larger than the theoretical value, but the attenuation coefficient in smaller model measures greater. Ultrasound severely attenuates in the sand and becomes the minimum in the range of 5cm. Frequency is not measured because of a serious dispersion of frequency. Attenuation coefficient of ultrasound in artificial core is impacted by the power and frequency of ultrasound and the porosity of core, it is greater when power and frequency of ultrasound is bigger and porosity of core is bigger. The study of attenuation of ultrasound provides reference for the study of damage relieving depth of ultrasound. Then, the artificial core polluted by clay is treated by ultrasound to study the damage relieving. The cores with different permeability, lengths and porosity are treated using ultrasound in the condition of different power and different time, which is used to study the impact of the core parameters and ultrasonic parameters when ultrasound is used to remove blocking. It is proved that the length of damage relieving using ultrasonic is about 7cm. The next step, orthogonal experiment is conducted to study the core parameters and ultrasonic parameters on the impact of damage relieving range of ultrasound, and it is considered that the ultrasonic power is the most critical factor which optimizes the ultrasonic parameters.