RESEARCH TOPIC


Dr. Kayhan Develi
Postdoctoral fellow

PhD degree from Istanbul Tech. Univ., Geological Eng. Dept., Turkey
(Primary supervisor: Dr. Mahir Vardar
Co-supervisor: Dr. Tayfun Babadagli - between 1996 and 2002)

(Visit period: January 23, 2008 - Sept. 23, 2008)


"Experimental modeling of single and multi phase flow in a rough-single fracture"


Dr. Develi specialized in the following research areas during his PhD research:

1- Fractal characterization of fracture surface roughness

2- Effect of surface roughness on the mechanical behavior of fractured rocks

His current post doctoral research is on “Experimental modeling of single and multi phase flow in a rough-single fracture”. Cube shaped samples taken from lithologically different types of rocks were subject to Brazilian tests to create artificial -single- fractures (Figure 1). Then, transparent replicas were casted from the original fractures (Figure 2). The surfaces of transparent fracture models were scanned and digitized by means of a computer-controlled surface scanning device (Figure 3) which was designed and developed duirng his doctoral study. A 3-D image of the surface is shown in Figure 4. Finally, different fractal methods were applied to 2-D surface data and the fractal dimensions of the surfaces were calculated. Currently, single and multi phase fluid flow tests are conducted on the transparent samples shown in Figure 2.



Figure 1: Fractured rock samples after the Brazilian tests and general view of the artificial fracture surfaces


Figure 2: Transparent models casted from original rock fracture surfaces


Figure 3: Computer-controlled surface scanning device (The new version of the “a new computer-controlled surface scanning device” previously introduced by Develi, Babadagli and Comlekci, 2000)


Figure 4: 3-D surface view of fracture sample Fr1 obtained from surface scanning process.



RELEVANT PUBLICATIONS

  1. Develi, K. and Babadagli, T., 1998. Quantification of natural fracture surfaces using fractal geometry. Mathematical Geology 30 (8), 971-998.

  2. Develi, K. and Babadagli, T., 2000. Author’s Reply to Comments on “Quantification of Natural Fracture Surfaces Using Fractal Geometry”, Mathematical Geology 32 (4) 517-520.

  3. Develi, K., Babadagli, T and Comlekci, C., 2000. A new computer controlled surface scanning device for measurement of fracture surface roughness, Comput. Geosci. 27 (3) 265–277.

  4. Babadagli, T. and Develi, K., 2001. On the application of methods used to calculate the fractal dimension of fracture surfaces, Fractals 9 (1) 105-128.

  5. Babadagli, T. and Develi, K., 2003. Fractal characteristics of rocks fractured under tension, Theoretical and Applied Fracture Mechanics 39, 73-88.

  6. Develi, K. and Vardar, M., 2006. Quantification of surface roughness and its effect on the shear strength of a discontinuity. Journal of ITU, Series D; Engineering, 5 (4) 69-82.

  7. Babadagli, T. and Develi, K., 1998. Fracture Surface Characterization by Fractal Methods and Effect of Fractal Dimension on Fluid Transport Efficiency, in: 12th Petroleum Cong. and Exh. of Turkey, Ankara, Turkey, Oct. 12-15, pp. 295-304.

  8. Babadagli, T. and Develi, K., 1998. Analysis of Fracture Development and Propagation Using Fractal Methods, in: 12th Petroleum Cong. And Exh. of Turkey, Ankara, Turkey, Oct. 12-15, pp.389-397

  9. Develi, K. and Vardar, M., 1998. Quantitative definition of discontinuity surface roughness by using fractal geometry, Proc. of the 4th National Rock Mech. Symp, 22-23 October, Zonguldak / Turkey, pp. 217-225

  10. Babadagli, T. and Develi, K., 2000. Fractal Analysis of Natural and Synthetic Fracture Surfaces of Geothermal Reservoir Rocks, in: 2000 World Geothermal Congress, Kyushu-Tohoku, Japan, May 28-June 10, pp. 2515-2520.

  11. Babadagli, T. and Develi, K., 2000. Fractal Fracture Surfaces and Its Effect on Fluid Displacement Efficiency, in: 31st Int.Geological Cong. Rio De Janeiro, Brasil, Aug. 6-17.

  12. Babadagli, T. and Develi, K., 2001. Fractal fracture surfaces and fluid displacement process in fractured rocks, Paper No. ICF100570OR, 10th Int. Conf. of Fracture, 3–7 December, Honolulu, Oahu, Hawaii.

  13. Develi, K., 2006. Quantification of surface roughness with theoretical and experimental methods for mechanical modeling of jointed rocks. PhD thesis, Istanbul Technical University, Istanbul, Turkey, 258 p.