A cleaning pig is designed to facilitate the removal of sediments in a drain or sewer. It is formed as a cylindrical device with shallow channels on the surface and is propelled through the pipe by the flow.
COD (Chemical Oxygen Demand)
Chemical oxygen demand is a measure of the total quantity of oxygen required to oxidize all organic material (biologically available, inert organic matter) into carbon dioxide and water, and oxidisable inorganic matter.
Domestic cold water covers the water that is used in a home for showering, cooking, etc. This water comes either from a water supply system delivering water to many households, or from a private well.
Colebrook-White's formula can be used to determine the friction coefficient (l) of a turbulent flow. The formula is normally used to create diagrams where the friction coefficient can be read.