Energy demand has increased significantly in recent years around the world as a result of rising population and improved transportation and technology. Nanotechnology is one of the latest passive ...

A new equation for accurate approximation of the Moody friction factor in the general gas-flow equation better approximates a wide range of Reynolds numbers than previously published equations. Other, ...

The methodology uses actual survey data and known surface hook loads for different operating conditions, such as tripping in, tripping out, and rotating off bottom, to arrive at appropriate friction ...

This paper investigates the friction coefficient of a moving liquid marble, a small liquid droplet coated with hydrophobic powder and floating on another liquid surface. A floating marble can easily ...

1.1 What is friction? Take this everyday example: when a coffee mug rests on a flat table, the kinetic frictional force is zero. There is no force trying to move the mug across the table, so there is ...