Hydraulic Simulation of Leakage in Post-Earthquake Water Supply Pipeline Network and Its Algorithm Improvement

Table 1

Pipe leakage forms and their calculation formula (according to document [7]).

Leak form	Circumferential loosening	Lateral cracks	Longitudinal cracks	Damaged pipe wall	Wall tear
Leakage area calculation formula
Parameter description	D is the diameter of the pipe (mm)	θ1 is the opening angle of the circular crack (°), which is taken as 0.5	L is the longitudinal crack length (mm), take 13
	k is a dimensionless constant, taking 0.3		The opening angle of θ2 longitudinal crack (°), take 0.1		W is the tearing width of the pipe wall (mm), take 12
	t is the thickness of annular separation (mm), take 10			k1, k2 are dimensionless constants, take 0.05	k is a dimensionless constant, taking 0.3
Schematic diagram