Effect of fiber on the rheological property of fracturing fluid

• The addition of fibers obviously increase the apparent viscosity of fracturing fluid.
• Higher increment in apparent viscosity of fracturing fluids is found at lower shear rate, higher fiber concentration.
• The addition of fibers enhances the shear-thinning behavior of fracturing fluid.

Fiber is often used in hydraulic fracturing, such as channel fracturing and FiberFRAC, to enhance the proppant carrying capacity of fracturing fluid and to prevent the dispersion of proppant-laden pulses. Fracture geometry and proppant distribution in the fracture depend largely on the rheological properties of the fracturing fluids. However, few studies currently have dealt with the rheological characterization of fracturing fluids containing fiber. This paper focuses on the effect of fiber on the rheological property of hydroxypropyl guar (HPG) base fluid. Substantial increment in apparent viscosity of fracturing fluid is observed, and the increment relies heavily on the shear rate, fiber concentration, thickening-agent concentration and test temperature. Higher increment in apparent viscosity is found at lower shear rate and higher fiber concentration. The test results shows that the non-Newtonian behavior of HPG base gels is enhanced with the addition of fiber. Therefore, rheological parameters of fiber-laden fracturing fluid should be employed in hydraulic fracture design instead of the parameters of the base gel.