Standard 6-Inch Throat Parshall Flume
Precision fabricated stainless steel flume with standardized converging, throat, and diverging sections.
Agricultural Engineering / Parshall Flume Calibration
FREE TO EXPLORELABORATORY 14 · AGRICULTURAL ENGINEERING
Parshall Flume Open-Channel Flow Discharge Calibration & Submergence
Calibrate a standard Parshall flume in an open irrigation channel, determine the free-flow power-law discharge rating equation, and evaluate the critical submergence limit. Explore interactive farm machinery simulation, irrigation hydraulics, and agricultural engineering telemetry.
FARM MACHINERY · SOIL & WATER · POST-HARVEST · STRUCTURES
Your virtual agricultural engineering laboratory.
LOGARITHM OF DISCHARGE LN(Q)—
FIELD & TEST CELL TELEMETRY
Ready to sample with ln(Head H_a) = -1.7429 ln(m).
Adjust ln(Head H_a), then execute agricultural trial.
Agricultural engineering telemetry and biosystems states are evaluated rigorously using 64-bit IEEE 754 precision. Residuals reflect ordinary least-squares regression across successive observations. Continuous data structures support high-fidelity agricultural and environmental modeling.
Agricultural assumptions and boundary condition limits
Flumes must be fabricated strictly to standardized ASTM/USBR dimensions; geometric scaling errors invalidate published discharge coefficients. Evaluated using a standard 6-inch (15.2 cm) throat width Parshall flume in free-flow regime across upstream heads from 0.05 m to 0.40 m.
Agricultural apparatus & field instrumentation sensors.
Hydraulic Tilting Open-Channel Flume
Laboratory flume canal 60 cm wide and 10 m long with recirculating water pump and tailwater gate.
Dual Point-Gauge Stilling Wells (H_a & H_b)
Measures upstream water depth H_a and throat depth H_b with 0.1 mm accuracy.
Magnetic Flowmeter Reference Sensor
Supplies independent benchmark volumetric discharge rate Q with 0.5% precision.
Adjustable Downstream Tailwater Weir
Modulates downstream water level to test free-flow versus submerged-flow regimes.
Digital Differential Pressure Transmitter
Continuously records water surface elevation heads in the stilling wells.
FOLLOW THE METHOD
A reason behind every step.
Calibrate a standard Parshall flume in an open irrigation channel, determine the free-flow power-law discharge rating equation, and evaluate the critical submergence limit. Standardized parameter settings: -2.9957, -2.5257, -2.1203, -1.7148, -1.3093, -0.9163 ln(m).
01
Flume Leveling & Zero Setting
Level the Parshall flume longitudinally and laterally in the channel. Set the stilling well point gauges to exactly zero against the flat crest of the flume converging floor.
02
Free-Flow Calibration Setup
Lower the downstream tailwater gate completely to ensure free-fall discharge, ensuring the submergence ratio H_b / H_a remains well below 0.60.
03
Initial Low-Flow Stabilization
Regulate pump throttle to deliver initial low discharge producing an upstream head H_a = 0.05 m (ln H_a = -2.9957), allowing water levels in the stilling wells to stabilize.
04
Synchronous Discharge Logging
Record the upstream head H_a from the stilling well and the reference discharge Q from the magnetic flowmeter simultaneously over 3 minutes.
05
Head Range Stepping
Increment pump discharge in five uniform stages to achieve upstream heads of 0.08, 0.12, 0.18, 0.27, and 0.40 m, recording H_a and Q for each flow rate.
06
Power-Law Logarithmic Regression
Transform H_a and Q into natural logarithms, plot ln Q versus ln H_a, and perform linear regression to determine the exponent n and coefficient C.
YOUR NOTEBOOK · 0 OBSERVATIONS
Turn measurements into agricultural engineering insight.
Points are your recorded observations. The solid regression line validates Parshall Flume Calibration mathematical scaling.
LINEAR REGRESSION FIT · y = mx + b
ln(Q) = n · ln(H_a) + ln(C) = 1.5500 · ln(H_a) + 0.3800
| # | Logarithm of Upstream Gauge Head ln(H_a) (ln(m)) | Logarithm of Discharge ln(Q) (ln(m³/s)) | ln(Upstream head H_a in m) | ln(Discharge Q in m³/s) | Remove |
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