hydReng (version 0.1.0)

pressflow_depth: Backwater Height Upstream A Inlet Under Pressure (Bernoulli)

Description

Calculates the backwater height upstream of an inlet (pipe or rectangle) under pressure (Bernoulli). The outlet is not submerged, e.g., the exit loss equals 0.

Usage

pressflow_depth(
  z0, z1, Q, Di = NULL, h = NULL, b = NULL, L, ks = NULL, kst,
  xi_e = 0.5, nu = 1.14e-6, calc_lam = "kst"
)

Value

Returns the backwater height upstream the inlet:

h0

Water depth upstream the inlet [m].

v

Flow velocity [m/s].

Arguments

z0

Absolute height of upper gate – upstream of the inlet [m.a.s.l].

z1

Absolute height of the pipe/rectangle vertical middle axis at lower gate [m.a.s.l].

Q

Flow [m^3/s].

Di

Diameter of pipe [m]. If Di is specified, h and b must be NULL.

h

Height of rectangle [m]. If h is specified, Di must be NULL.

b

Width of rectangle [m]. If b is specified, Di must be NULL.

L

Length of pipe [m].

ks

Equivalent sand roughness [m].

kst

Roughness [m^(1/3)/s].

xi_e

Entrance loss [-]. Default = 0.5.

nu

Kinematic viscosity [m^2/s]. Default = 1.14e-6.

calc_lam

Defines if lambda should be calculated with ks or kst.

Examples

# Flow in a pipe under pressure with ks value
pressflow_depth(z0 = 415, z1 = 413, Q = 5.18, L = 20, Di = 1,
                ks = 0.01, calc_lam = "ks")

# Flow in a rectangle under pressure with kst value
pressflow_depth(z0 = 415, z1 = 413, Q = 13.7, L = 20, b = 2, h = 1,
                kst = 60, calc_lam = "kst")