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Articles
by
Sonny Irawan |
Total Records (
3 ) for
Sonny Irawan |
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Ghulam Abbas
,
Sonny Irawan
,
Sandeep Kumar
,
Khalil Rehman Memon
and
Shuaib Ahmed Khalwar
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Polymers have been used in oil well cementing for improving
the properties of cement slurry. Polysaccharides and their derivatives are mostly
used as multifunctional additive in cement slurry. But these polymers present
number of limitations at high temperature. Polysaccharides do not reveal an
appropriate thickening of viscosity in cement slurry at high temperature which
turn gives the fluid loss, gas migration and loss of economics. It is necessary
to use such type of polymer in cement slurry that increases viscosity at high
temperature. Therefore, this study present Hydroxypropylmethylcellulose (HPMC)
polymer that is able to increase viscosity at high temperature and improve the
properties of cement slurry. Laboratory experiments were performed to determine
the characteristics of HPMC based cement slurry. The viscosity of 2 wt.% solution
of HPMC polymer was determined at various temperatures. Further 0.20-0.50 gallon
sack-1 concentration of HPMC polymer was used in cement slurry to
evaluate the API properties of HPMC based cement slurry in term of rheology,
free water, fluid loss, thickening time and compressive strength. It was observed
that HPMC polymer was stable at high temperature and increases viscosity at
elevated temperature. In cement slurries HPMC polymer resulted less than 50
mL of fluid loss; zero free water and predictable thickening time as well as
enhanced final compressive strength with some other additives. The experimental
result showed that HPMC has significantly improved the properties of cement
slurry at high temperature. |
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Mahmood Bataee
and
Sonny Irawan
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This study has reviewed the geomechanical considerations and
applications in reservoir modeling. Geomechanical studies are applied in the
reservoir to establish some features as field subsidence/inflation and stability.
The reservoir stress alters with the change in the pressure and temperature
either by production or EOR injection/thermal methods. The field subsidence/inflation
can damage surface facilities. The change in field new stress state could lead
to the failure in some rock types and faulting. The change in pressure and temperature
leads to the change in stress. The resulted strain changes the porosity, permeability
and the consequently the new pressure distribution will be obtained. Due to
this change the stress state should be updated by coupling studies. There are
some methods to investigate the effects of geomechanics on reservoir simulation,
as implicit, explicit, iterative and psudo-coupling method. Many researchers
have tried to model the stress in the reservoir for more than thirty years.
They have governed various equations to investigate the flow, thermal and chemical
effect in stress redistribution. They have done their studied for many different
conditions in different flow phases. However, there are lots of reservoir studies
that did not consider geomechanics. |
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Titus N. Ofei
,
Sonny Irawan
and
William Pao
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In drilling operations, estimation of pressure drop and cuttings concentration in the annulus is very complex due to the combination of interacting drilling parameters. Over the years, many investigators have developed empirical correlations to determine these parameters, however, the use of these correlations are limited to their experimental data range and setup and cannot be applicable to all cases. Computational Fluid Dynamics (CFD) method has been widely accepted as the best technique, not only due to its ability to handle complex multiphase flow problems but also its ability to handle unlimited number of physical and operational conditions. The present study examines the effects of annular diameter ratio, flow rate (fluid velocity), drillpipe rotation and fluid type on pressure drop and cuttings concentration in eccentric horizontal wellbore using CFD method. The annular diameter ratio varies from 0.64-0.90 with the drillpipe positioned at eccentricity of 0.623 and rotating about its own axis at 80 and 120 rpm. The drilling fluids were modelled using Newtonian and Power-Law fluids. Results show that at diameter ratio of 0.90, pressure drop is very dramatic yet, the amount of cuttings transported remained almost constant for all fluid velocities. Experimental pressure drop and cuttings concentration data compared favourably with simulation data with mean percentage error of 0.84 and 12%, respectively, confirming the validity of the current model. |
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