Behavior of electrostatic charge and distribution of velocity of flowing petroleum in relaxation pipe

The electrostatic charge in petroleum generated in a filter or a transportation pipe is very hazardous and has to be reduced before the petroleum is poured into a storage tank. It is known that the relaxation pipe(hereafter, noted as RP) is effective for this purpose. Many factors of RP have discussed in earlier studie [1],[2], e.g. conductivity, viscosity and mean flow velocity of petroleum sample, geometrical scale of RP and so on versus relaxation factor (reduction rate of electrostatic charge in RP). For increasing the effect to discharge the electrostatic charge in RP, the distribution of velocity of flowing petroleum in RP must be known accurately.