A self-propelling colonoscopic device moving inside the colonic tube should be able to periodically grip safely to the colonic wall as well as to manipulate the generated friction. The feasibility of achieving high grip and friction manipulation by covering the device with mucoadhesive films is experimentally tested. More precisely, the frictional behaviour of mucoadhesive films inside the colo...

The axial stress and deformation of high temperature high pressure deviated gas wells are studied. A new model is multiple nonlinear equation systems by comprehensive consideration of axial load of tubular string, internal and external fluid pressure, normal pressure between the tubular and well wall, and friction and viscous friction of fluid flowing. The varied temperature and pressure fields...

We consider a widely used higher order glacier flow model with a variety of parameterizations of wall slip, including Coulomb friction, regularized Coulomb friction laws and a power law. Mathematically, the Coulomb friction problem is found to be analogous to a classical friction problem in elasticity theory. We specifically analyze the case in which slip is possible everywhere at the boundary,...

In this paper, the axial stress and deformation of high temperature high pressure super-deep deviated gas wells are studied. A new model presents multiple nonlinear equation systems, which comprehensively consider the axial load of the tubular string, internal and external fluid pressure, normal pressure between the tube and well wall, friction and the viscous friction of fluid flowing under va...

Existing data for soft magnetic materials of critical current for domain-wall motion, wall speed driven by a magnetic field, and wall electrical resistance, show that all three observable properties are related through a single parameter: the wall mobility μ. The reciprocal of μ represents the strength of viscous friction between domain wall and conduction-electron gas. And μ is a function of t...

The Galerkin finite element method is used to solve the three dimensional continuity, momentum and energy equations for laminar Newtonian and power-law model non-Newtonian flow through horizontal circular tube. The governing equations are non-dimensionalized with respect to specific variables and converted into algebraic equations using appropriate elements. To accelerate convergence a combinat...

Analysis of intrinsic irreversibility and heat transfer in a buoyancy-driven changeable viscosity liquid along an incline heated wall with convective cooling taking into consideration the heated isothermal and isoflux wall is investigated. By Newton’s law of cooling, we assumed the free surface exchange heat with environment and fluid viscosity is exponentially dependent on temperature. Appropr...

In this study, turbulent compressible gas flow in a rectangular micro-channel is numerically investigated. The gas flow assumed to be in the subsonic regime up to Mach number about 0.7. Five low and high Reynolds number RANS turbulence models are used for modeling the turbulent flow. Two types of mesh are generated depending on the employed turbulence model. The computations are performed for R...

Freshwater biofilms are currently being studied to determine their effect on the capacity of hydroelectric power scheme canals and the structure of their turbulent wall layers. Mean velocity boundary layer profiles and total drag measurements have been conducted in a purpose built recirculating water tunnel on freshwater biofilms grown in a hydroelectric canal. Two different fouled surfaces wer...

Recently the thermal friction on an expanding bubble from cosmic first-order phase transition has been calculated to all orders of interactions between wall and plasma, leading a $\gamma^2$-scaling instead previously estimated $\gamma^1$-scaling for exerted fast-moving with Lorentz factor $\gamma$. We propose first time effective equation motion (EOM) in presence arbitrary $\gamma$-scaling comp...