油层物理课件 chap3.2

Mercury does not wet the glass
Water wets the rock
Wettability is the ability of a 1iquid to spread over the surface of a solid under the action of molecular forces.
Shandong Provincial Excellent Course, 2008
Shandong Provincial Excellent Course, 2008
1 Wettability (润湿性)
1.1 Wettability and contact angle (接触角)
mercury shrinks to a sphere. water spreads on the glass.
• Clean silica and carbonates are normally water-wet in their clean state • Some clay minerals (montmorillonite) is strongly waterwettability • Clay minerals containing irons, such as chamosite (鲕状绿 泥石) can absorb surfactant----- oil-wet. • Organic materials are usually hydrophobic(憎水的) .
Shandong Provincial Excellent Course, 2008
1.1 Wettability and contact angle (接触角)
The contour of a drop on the surface of a so1id along which the three phases - solid, liquid, and gas - come in contact, is known as the wetted perimeter (润湿周界).
3.2 Wettability of reservoir rocks and distribution of oil and water in pores
SUN Ren-yuan Room 648, Engineering Building B
Oct., 2008wk.baidu.com
Shandong Provincial Excellent Course, 2008
Shandong Provincial Excellent Course, 2008
1.1 Wettability and contact angle (接触角) Oil-water system:
water
oil
θ
θ
water
oil
θ>90º oil-wet (hydrophobic 憎水的)
θ<90º water-wet (hydrophilic 亲水的)
Shandong Provincial Excellent Course, 2008
1.2 Adhesion tension (附着张力)
Young’s equation:
23 13 12 cos AT
adhesion tension
cos 23 13 / 12
23 13, AT 0, 90 water-wet
23 13, AT 0, 90 oil-wet
The essential(本质) of wettability is to reduce the surface
free energy of a solid.
Shandong Provincial Excellent Course, 2008
2 Factors affecting the wettability of reservoir rocks
Shandong Provincial Excellent Course, 2008
1.1 Wettability and contact angle (接触角)
1: water 2: gas
Liquid-air system: •θ<90º 1iquid wets a solid surface •θ = 90º liquid partially wets the solid •θ > 90º liquid does not wet the solid
Contents
• Interfacial tension (界面张力) • Wettability (润湿性) of reservoir rocks and distribution of oil and water in pores • Capillary pressure （毛管压力） • Relative permeability (相对渗透率)
Shandong Provincial Excellent Course, 2008
1.1 Wettability and contact angle (接触角)
Angle of contact (接触角): the angle formed between the surface of a solid and the tangent to the surface of the drop at the point of contact with the solid. By convention, the contact angle (θ) is measured through the denser phase and ranges from 0ºto 180º.
2.1 Mineral composition of rock surface and types of fluids
异辛烷
异喹啉
环烷酸
Shandong Provincial Excellent Course, 2008
2.1 Mineral composition of rock surface and types of fluids