Experimental Investigation on Compressive Strength, Ultrasonic Characteristic and Cracks Distribution of Granite Rock Irradiated by a Moving Laser Beam

Kuang, Lianfei; Sun, Lipeng; Yu, Dongxu; Wang, Yijiang; Chu, Zhaoxiang; Darkwa, Jo

Abstract

Efficient fracturing is the key issue for the exploitation of geothermal energy in a Hot Dry Rock reservoir. By using the laser irradiation cracking method, this study investigates the changes in uniaxial compressive strength, ultrasonic characteristics and crack distributions of granite specimens by applying a laser beam under various irradiation conditions, including different powers, diameters and moving speeds of the laser beam. The results indicate that the uniaxial compressive strength is considerably dependent on the power, diameter and moving speed of the laser beam. The ultrasonic-wave velocity and amplitude of the first wave both increase with a decreased laser power, increased diameter or moving speed of the laser beam. The wave form of irradiated graphite is flattened by laser irradiation comparing with that of the original specimen without laser irradiation. The crack angle and the ratio of the cracked area at both ends are also related to the irradiation parameters. The interior cracks are observed to be well-developed around the bottom of the grooving kerf generated by the laser beam. The results indicate that laser irradiation is a new economical and practical method that can efficiently fracture graphite.

Citation

Kuang, L., Sun, L., Yu, D., Wang, Y., Chu, Z., & Darkwa, J. (2022). Experimental Investigation on Compressive Strength, Ultrasonic Characteristic and Cracks Distribution of Granite Rock Irradiated by a Moving Laser Beam. Applied Sciences, 12(20), Article 10681. https://doi.org/10.3390/app122010681

• Journal Article Type: Article
• Acceptance Date: Oct 19, 2022
• Online Publication Date: Oct 21, 2022
• Publication Date: Oct 1, 2022
• Deposit Date: Oct 21, 2022
• Publicly Available Date: Oct 21, 2022
• Journal: Applied Sciences (Switzerland)
• Electronic ISSN: 2076-3417
• Publisher: MDPI
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 20
• Article Number: 10681
• DOI: https://doi.org/10.3390/app122010681
• Keywords: Fluid Flow and Transfer Processes; Computer Science Applications; Process Chemistry and Technology; General Engineering; Instrumentation; General Materials Science
• Public URL: https://nottingham-repository.worktribe.com/output/12623859
• Publisher URL: https://www.mdpi.com/2076-3417/12/20/10681