纳米SiO_(2)/酚醛树脂复合材料裂纹扩展行为分析及力学性能研究

Analysis of crack propagation behavior and mechanical properties of nano-SiO_(2)/phenolic resin composites

油气井出砂是疏松砂岩油气藏开采面临的主要矛盾。树脂固结人工井壁防治细粉砂效果优良,可实现复杂井况下的无筛管防砂,是目前油田应用最广泛的化学防砂方法,决定其防砂成败的关键是树脂的固结性能。借助扩展有限元(XFEM)对裂纹经过单个粒子、一对粒子、均匀分布的多个粒子进行数值模拟,研究纳米粒子对裂纹扩展路径和损伤耗散能量的影响,发现纳米SiO_(2)对裂纹影响区间为5个纳米粒子直径,纳米SiO_(2)的最佳质量分数为树脂基体的3%。树脂样条的抗冲击强度和树脂防砂体的抗压强度的测定结果表明,纳米SiO_(2)质量分数为3%时,树脂样条抗冲击强度提高39%左右,树脂防砂体抗压强度提高36%左右,显著改善了酚醛树脂的力学性能。

Sand production in Wells is the main contradiction facing the exploitation of unconsolidated sandstone oil and gas reservoirs.Resin consolidated artificial wellbore is the most widely used chemical sand control method in oil fields at present because of its excellent effect on fine sand control,which can achieve screen-free sand control under complex well conditions.The extended finite element method(XFEM)was used to simulate the crack passing through a single particle,a pair of particles and a plurality of evenly distributed particles,and the influence of nanoparticles on the crack growth path and damage dissipation energy was studied.It was found that the influence range of nano-SiO_(2)on the crack was 5 nanoparticle diameters,and the best mass fraction of nano-SiO_(2)was 3%of the resin matrix.The results of measuring the impact strength of resin spline and the compressive strength of resin sand control body show that when the mass fraction of nano-SiO_(2)is 3%,the impact strength of resin spline increases about 39%and the compressive strength of resin sand control body increases about 36%,which significantly improves the mechanical properties of phenolic resin.