The addition of an environmental remediation modifier—polymer solution—to a Newtonian fluid expands the distribution of remediation agents injected in situ into saturated aquifers (affecting plume velocity and deformation), enhancing remediation efficiency. However, the effect of the flow properties of the polymer solution on the macroscopic transverse dispersion remains poorly understood. In this work, a transparent thin-layer two-dimensional sandbox was constructed to simulate the aquifer, and the transverse distribution range of colored solute—permanganate solution and viscous shear-thinning fluid (permanganate solution + xanthan gum)—was captured in real-time by a camera device during transport in porous media. The boundary dispersion coefficient was obtained by fitting a breakthrough curve of the boundary concentration, while the overall plume dispersion coefficient was determined via image moment analysis. The effects of fluid rheology and heterogeneity on the transverse mixing of the plume were analyzed, and the mechanism of viscoelasticity-induced transverse dispersion and mixing enhancement was summarized. The results indicated that the anisotropic stress generated by polymer fluid deformation at high water velocity increased the fluctuation and transverse distribution of the plume, while higher-viscosity polymers increased the initial extrusion swelling and additional compressive stress, covering a larger area. Xanthan gum enhanced the transverse distribution of the plume mainly through initial injection-extrusion expansion effect, viscoelastic stability of the post-injection part, and streamline crossing attributed to elastic turbulence. This study also verified that the shear-thinning fluid enhanced the effect of transverse dispersion and mixing under heterogeneous conditions, providing insights applicable to groundwater remediation.
Skip Nav Destination
Article navigation
April 2023
Research Article|
April 10 2023
Transverse mixing zone under dispersion in porous media: Effects of medium heterogeneity and fluid rheology
Du Zhipeng (杜志鹏)
;
Du Zhipeng (杜志鹏)
(Formal analysis, Investigation, Methodology, Software, Visualization, Writing – original draft, Writing – review & editing)
Key Laboratory for Water and Sediment Sciences of Ministry of Education, School of Environment, Beijing Normal University
, Beijing 100875, China
Search for other works by this author on:
Chen Jiajun (陈家军)
;
Chen Jiajun (陈家军)
a)
(Conceptualization, Funding acquisition, Investigation, Project administration, Resources, Supervision, Writing – review & editing)
Key Laboratory for Water and Sediment Sciences of Ministry of Education, School of Environment, Beijing Normal University
, Beijing 100875, China
a)Author to whom correspondence should be addressed: jeffchen@bnu.edu.cn
Search for other works by this author on:
Ke Shengnan (柯胜男)
Ke Shengnan (柯胜男)
(Conceptualization, Project administration, Supervision)
Key Laboratory for Water and Sediment Sciences of Ministry of Education, School of Environment, Beijing Normal University
, Beijing 100875, China
Search for other works by this author on:
a)Author to whom correspondence should be addressed: jeffchen@bnu.edu.cn
Physics of Fluids 35, 043105 (2023)
Article history
Received:
January 09 2023
Accepted:
March 25 2023
Citation
Zhipeng Du, Jiajun Chen, Shengnan Ke; Transverse mixing zone under dispersion in porous media: Effects of medium heterogeneity and fluid rheology. Physics of Fluids 1 April 2023; 35 (4): 043105. https://doi.org/10.1063/5.0141837
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Sign in via your Institution
Sign in via your InstitutionPay-Per-View Access
$40.00