Rheology of foamed cement

14Foamed cement is a critical component for wellbore stability. The mechanical performance of a foamed 15 cement depends on its microstructure, which in turn depends on the preparation method and attendant 16 operational variables. Determination of cement stability for field use is based on laboratory testing 17 protocols governed by API Recommended Practice 10B-4 (API RP 10B-4, 2015). However, laboratory 18 and field operational variables contrast considerably in terms of scale, as well as slurry mixing and 19 foaming processes. Here, laboratory and field operational processes are characterized within a physics-20 based framework. It is shown that the "atomization energy" imparted by the high pressure injection of 21 nitrogen gas into the field mixed foamed cement slurry is -by a significant margin -the highest energy 22 process, and has a major impact on the void system in the cement slurry. There is no analog for this high 23 energy exchange in current laboratory cement preparation and testing protocols. Quantifying the energy 24 exchanges across the laboratory and field processes provides a basis for understanding relative impacts of 25 these variables on cement structure, and can ultimately lead to the development of practices to improve 26 cement testing and performance. 27 28

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“…Foamed cement slurry is a non-Newtonian mixture (Ahmed et al, 2009). Consequently, computation of 19…”

Section: Surface Tension 10mentioning

confidence: 99%

Relationship between operational variables, fundamental physics and foamed cement properties in lab and field generated foamed cement slurries

Glosser

Kutchko

Benge³

et al. 2016

Journal of Petroleum Science and Engineering

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“…In parallel, more fundamental approaches have been developed on the basis of a first-order approximation. For example, a simplified version of the Barthel-Biesel & Chim model for viscoelastic deformable objects has been suggested to describe the behaviour of foamed cements under flow by Ahmed et al (2009):…”

Section: à5mentioning

confidence: 99%

“…Figure 1 highlights the differences between the respective bubble topologies at rest: spherical in foamy fluids, slightly deformed spheres in wet foams and "deformed ellipsoidal" in conventional airwater bubbly flows. Foamy fluids cover many typical industrial situations, such as foamed cement (Ahmed et al, 2009), foamy oils (Abivin et al, 2009) or food foams (Murray et al, 2011) but they also describe bubbles in magma (Pal, 2003). Even though the presence of foaming agents adsorbed at the interface is often required to delay bubble coalescence, the role of interfacial properties is reduced in comparison to wet or dry foams because it is counterbalanced by the influence of the bulk properties (mainly viscosity) and the role of the microstructure of the continuous phase, such as the partial coalescence of fat in whipped cream (Hotrum et al, 2005).…”

Section: Introductionmentioning

confidence: 99%

Development of a Model Foamy Viscous Fluid

Vial

Narchi²

2013

Oil Gas Sci. Technol. – Rev. IFP Energies nouvelles

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IFP Energies nouvelles International Conference Rencontres Scientifiques d'IFP Energies nouvellesRe´sume´-De´veloppement d'un mode`le de dispersion gaz-liquide de type mousse liquide visqueuse -L'objectif est de de´velopper un fluide mode`le repre´sentatif des « mousses liquides », c'est-a`-dire pre´sentant un taux de vide en dec¸a`de l'empilement ale´atoire de sphe`res, dont les proprie´te´s rhe´ologiques et la stabilite´peuvent eˆtre pre´dites. Tout d'abord, la pre´paration de ces fluides mode`les sera de´crite a`la fois en termes de formulation et de proce´de´s. Ensuite, les re´sultats expe´rimentaux seront discute´s. Ceux-ci montrent que des mousses liquides visqueuses mode`les pre´sentant une distribution de tailles de bulles monomodales ont e´te´obtenues avec un taux de vide entre 25 % et 50 % (v/v). Leurs proprie´te´s viscoe´lastiques en e´coulement et aux faibles de´formations re´sultent des interactions entre la formulation de la phase continue, le taux de vide et le diame`tre des bulles. Leur viscosite´apparente peut eˆtre de´crite par un mode`le de Cross et la viscosite´a`cisaillement nul peut eˆtre pre´dite par le mode`le de Mooney jusqu'a`un taux de gaz de 40 %. Les mesures en mode harmonique ont montre´que les re`gles de CoxMerz et de Laun s'appliquent quand le nombre capillaire Ca est infe´rieur a`0,1. L'e´tendue du plateau Newtonien a`faible cisaillement de´croıˆt lorsque le taux de vide augmente ou lorsque la taille des bulles diminue. Dans le domaine rhe´ofluidifiant, la contrainte de cisaillement varie proportionnellement a`Ca 1/2 , comme dans les mousses humides pre´sentant des interfaces immobilise´es. Finalement, les mousses liquides visqueuses obtenues ont pu eˆtre cisaille´es jusqu'a`des valeurs de Ca de 0,1 sans modifier leur microstructure. La stabilite´de ces fluides au repos atteint plusieurs heures et elle augmente avec le taux de vide a`cause des contraintes ste´riques entre les bulles ; ils constituent donc des fluides mode`les inte´ressants pour l'e´tude des mousses liquides visqueuses pre´sentant un taux de vide en dec¸a`de l'empilement ale´atoire de sphe`res.Abstract -Development of a Model Foamy Viscous Fluid -The objective is to develop a model viscous foamy fluid, i.e. below the very wet limit, the rheological and stability properties of which can be tuned. First, the method used for the preparation of foamy fluids is detailed, including process and formulation. Then, experimental results highlight that stable foamy fluids with a monomodal bubble size distribution can be prepared with a void fraction between 25% and 50% (v/v). Their viscoelastic properties under flow and low-strain oscillatory conditions are shown to result from the interplay between the formulation of the continuous phase, void fraction and bubble size. Their apparent viscosity can be described using the Cross equation and zero-shear Newtonian viscosity may be predicted by a Mooney equation up to a void fraction about 40%. The Cox-Merz and the 2013129 Laun's rules apply when the capillary number Ca is low...

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“…An index related to the setting property is needed to describe quantitatively the flow or injection processes in the crack. However, only rheological parameters can reflect the general change trend of the flow state according to current research studies (Ahmed et al, 2009). ISF is a concentrated aqueous suspension, with cement content in the slurry of more than 60%.…”

Section: Introductionmentioning

confidence: 99%

Thermal insulation and setting property of inorganic solidified foam

Lü

Qin

Jia

et al. 2015

Advances in Cement Research

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Thermal insulation and setting properties are considered to be two significant parameters when inorganic solidified foam (ISF) is applied to control and extinguish coal fires. Based on studies concerning the thermal properties of porous media and experimental research on the relationship between porosity and the addition of aqueous foam, an equation describing the change in thermal conductivity with aqueous foam volume is deduced and then amended.Microscopic analysis of the process of setting is conducted by scanning electron microscopy. The results show that the coagulation of a single bubble wall and bubbles connecting with each other lead the ISF to lose fluidity gradually. A loss of fluidity time (LFT) index is then proposed on the basis of field process requirements and the aforementioned microscopic analysis, and a home-made instrument to test LFT is developed. Effects of aqueous foam volume and accelerator type, along with its addition quantity, on the LFT of ISF are investigated. The relationship equation provides a theoretical foundation for steerable adjustment of the LFT. Furthermore, under the restriction of cost, thermal conductivity threshold and LFT, the parameters of the feasible construction state areas of four different accelerators were compared; in this study AC3 was found to be the most appropriate accelerator. NotationA accelerator amount (wt%) a, b, c coefficients F aqueous foam volume (ml) K e effective thermal conductivity (W/m K) k g thermal conductivity of gaseous phase (W/m K) k s thermal conductivity of solid phase (W/m K) V f aqueous foam volume (ml) å porosity (%) r true density (kg/m 3 ) r 0 dry density (kg/m 3 )

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Rheology of foamed cement

Cited by 61 publications

References 18 publications

Relationship between operational variables, fundamental physics and foamed cement properties in lab and field generated foamed cement slurries

Relationship between operational variables, fundamental physics and foamed cement properties in lab and field generated foamed cement slurries

Development of a Model Foamy Viscous Fluid

Thermal insulation and setting property of inorganic solidified foam

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