Experimental Investigation for Simulating High Power Laser Perforation under Pressure

Procedure: Initial tests were performed on cores of Berea sandstone and limestone under various conditions of axial, pore and confining pressures. For all cases, the laser settings remained the same.Full output power of 3.5 kW was applied continuously to each sample through the sapphire window of the pressure cell with a focused beamdiameter of 0.889 cm (0.35 in)over 8.0 s. The amount of laser exposure time was calculated from previous laser rock interactions to allow penetration into the core without risk of penetrating the core’s full length and avoiding possible damage to the pressure cell.