Velocity gradient to Parshall meter

Input data

Flow (Q)

Temperature

Flume width (W)

Downstream height (Yj)

Output data

Velocity gradient

Head loss

Critical yj

Detention time

Description

Given the water temperature, the Parshall flume width, the flow through it, and the tailwater height, this calculation determines the velocity gradient in the stretch downstream from the throat.

ParshallParshall

Inputs

Parameter
Default units
Description
Flow (Q)
L/s
Volumetric flow through the Parshall flume
Temperature
°C
Water temperature
Flume width (W)
in
Width of the Parshall flume throat
Downstream height (Yj)
m
Tailwater height at the downstream section of the Parshall flume

Outputs

Parameter
Default units
Description
Flow (Q)
m³/s
Volumetric flow through the Parshall flume
Velocity gradient
s⁻¹
Velocity gradient in the downstream section
Head loss (hf)
m
Head loss along the analyzed section
Critical yj
m
Critical height of the liquid layer
Detention time (tdet)
s
Water detention time within the Parshall flume

References

  • VIANNA, Marcos Rocha. Produção, Reservação e Distribuição de Água. e-book. Belo Horizonte: Bloom, 2021.