Screw be an appropriate choice. The left side pedal of a bicycle has a left-hand thread. More generally, screw may mean any helical device, such as a clamp, a micrometer, a ship's propeller, or an Archimedes' screw water pump. There is no universally accepted distinction between a screw and a bolt. A simple distinction that is often true, although not always, is that a bolt passes through a substrate and takes a nut on the other side, whereas a screw takes no nut because it threads directly into the substrate (a screw "screws into something", a bolt "bolts several things together").
Archimedes number forced convection dominates. When the density difference is due to heat transfer (e.g. fluid being heated and causing a temperature difference between different parts of the fluid), then we may write where: Doing this gives the Grashof number, i.e. the Archimedes and Grashof numbers are equivalent but suited to describing situations where there is a material difference in density and heat transfer causes the density difference respectively. The Archimedes number is related to both the Richardson number and Reynolds number via Archimedes number In viscous fluid dynamics, the Archimedes number (Ar) (not to be confused with Archimedes' constant, π), named