A comparative study on the rheology and wave dissipation of kaolinite and natural Hendijan Coast mud, the Persian Gulf

Abstract

The objective of this paper is to investigate the rheological behavior of kaolinite and Hendijan mud, located at the northwest part of the Persian Gulf, and the dissipative role of this muddy bed on surface water waves. A series of laboratory rheological tests was conducted to investigate the rheological response of mud to rotary and cyclic shear rates. While a viscoplastic Bingham model can successfully be applied for continuous controlled shearstress tests, the rheology of fluid mud displays complex viscoelastic behavior in time-periodic motion. The comparisons of the behavior of natural Hendijan mud with commercial kaolinite show rheological similarities. A large number of laboratory wave-flume experiments were carried out with a focus on the dissipative role of the fluid mud. Assuming four rheological models of viscous, Kelvin-Voigt viscoelastic, Bingham viscoplastic, and viscoelastic-plastic for fluid mud layer, a numerical multi-layered model was applied to analyze the effects of different parameters of surface wave and muddy bed on wave attenuation. The predicted results based on different rheological models generally agree with the obtained wave-flume data implying that the adopted rheological model does not play an important role in the accuracy of prediction.

A Numerical Study on Surface Wave Evolution Over Viscoelastic Mud

“…The model is used to study the effect of viscoelasticity on surface wave evolution. A comparison between the results of numerical wave model and the laboratory experiments of Soltanpour and Samsami (2011) confirms the accuracy of the numerical model. Figure (1) shows the variation of damping rate with surface wave frequency for various values of mud shear modulus.…”

Acoustic wave propagation in gassy porous marine sediments: The rheological and the elastic effects

“…First, the damping expression (34) assumes a 1/ dependence between the elastic and viscous responses of the sediment, and combines both dissipation mechanisms into one single term. In contrast, experimental studies [39,[45][46][47][48][49] that have reported both the shear and the viscous properties (flow curves) of sediments do not suggest a straightforward 1/ dependence between the two. The elastic and the viscous responses may vary individually, depending on the strain amplitude and/or frequency ranges (in for example, shear viscosity [58,59] and elastic modulus [61]).…”

“…The elastic and the viscous responses may vary individually, depending on the strain amplitude and/or frequency ranges (in for example, shear viscosity [58,59] and elastic modulus [61]). These may furthermore depend on the salinity, the mineralogical composition and the concentration [46,48]. Second, there exists a discrepancy because of the use of Re( * ) in the resonance frequency expression (35) and Im( * ) in the damping coefficient (34).…”

“…Furthermore, the current paper proposes the use of sediment viscosity values obtained from rheological experiments [45][46][47][48][49].…”

An experimental and numerical investigation on wave‐mud interactions

“…On the other hand, nonlinear models have the capability of being extended from small amplitude wave to nonlinear wave, which may enhance or reduce surface energy dissipation. Enhanced or reduced damping rates are observed in the literature using different wave heights of constant wave frequency [e.g., Nagai et al, 1984;Sakakiyama and Bijker, 1989;Liu et al, 2011;Soltanpour and Samsami, 2011]. One of the overarching goals of studying wave-mud interactions is to be able to inversely estimate the properties of muddy seabeds, such as the mud layer thickness, viscosity, and density [Rogers and Holland, 2009;Sheremet et al, 2011;Tahvildari and Kaihatu, 2011].…”