The accurate control of the wellbore pressure not only prevents lost circulation/blowout and fracturing formation by managing the density of the drilling fluid, but also improves productivity by mitigating reservoir damage. Calculating the geothermal pressure of a geothermal well by constant parameters would easily bring big errors, as the changes of physical, rheological and thermal properties...

Wellbore stability evaluation is one of the important applications rock mechanics and should be regarded to prevent instabilities that may develop in wells for various reasons (such as complex field conditions, interaction between drilling fluid, directional etc.). The saturation rocks by fluids causes significant changes on mechanical properties rocks. However level these variations changed du...

Abstract Wellbore instability problems cause nonproductive time, especially during drilling operations in the shale formations. These include stuck pipe, caving, lost circulation, and tight hole, requiring more time to treat therefore additional costs. The extensive hole collapse problem is considered one of main challenges experienced when Zubair formation. In turn, it caused by increasing wel...

Wellbore instability is one of the major problems that hamper the drilling speed in Halfaya Oilfield. Comprehensive analysis of geological and engineering data indicates that Halfaya Oilfield features fractured shale in the Nahr Umr Formation. Complex accidents such as wellbore collapse and sticking emerged frequently in this formation. Tests and theoretical analysis revealed that wellbore inst...

Wellbores in Enhanced Geothermal System extends several kilometers from the ground surface, providing large heat transfer areas between the flowing fluid and the surrounding formations. Various techniques and approximations to model wellbore heat transfer have been presented in the literature. Most of the wellbore simulators assume steady one-dimensional flowing without considering heat transfe...

Hydraulic dispersion in porous media and in fracture networks results in the spreading of the timedependent tracer signal. In geothermal reservoirs the wellbore often intersects fractures that are separated by tens or even hundreds of meters. The mixing in the wellbore at those separated fractures is also a source of dispersion, since tracer signals sampled at the wellhead are a mixture of the ...