Experimental study on fracture initiation by pressure pulses

摘要

A new testing device has been developed which can be utilized to study the dynamic fracture initiation by pressure pulses. Instead of using propellant gas, the device employs a falling weight to impact on the piston that compresses the borehole fluid and transmits a dynamic pressurization to the simulated wellbore, The device is instrumented to measure the pressure pulses in the simulated borehole and in the confining chamber. The fracture patten can directly be observed and examined. a systematic work has been done to calibrate the set-up and to identify the factors for controlling the pressurization rate.