Rigid-Wall Constant-Head Soil Permeameter
Holds 7.5 cm diameter soil core with porous stone plates and adjustable overflow weir.
Agricultural Engineering / Saturated Hydraulic Conductivity
FREE TO EXPLORELABORATORY 12 · AGRICULTURAL ENGINEERING
Constant-Head Soil Saturated Hydraulic Conductivity (K_sat) Determination
Determine the saturated hydraulic conductivity (K_sat) of agricultural soil cores using a constant-head permeameter and verify Darcy's linear filtration law. Explore interactive farm machinery simulation, irrigation hydraulics, and agricultural engineering telemetry.
FARM MACHINERY · SOIL & WATER · POST-HARVEST · STRUCTURES
Your virtual agricultural engineering laboratory.
DARCY DISCHARGE VELOCITY V—
FIELD & TEST CELL TELEMETRY
Ready to sample with Gradient i = 1.3 m/m.
Adjust Gradient i, 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
Rigid-wall cells do not permit confining radial stress, making them susceptible to edge effects in swelling clay soils. Evaluated using undisturbed sandy loam soil core (diameter 7.5 cm, length 10.0 cm, dry bulk density 1.45 g/cm³) using de-aired water at 20°C.
Agricultural apparatus & field instrumentation sensors.
Constant-Head Reservoir Tank
Supplies de-aired water at precisely regulated upstream hydraulic head elevation.
Differential Piezometer Manometer Board
Measures upstream and downstream pressure heads with 1.0 mm water column precision.
Graduated Volumetric Effluent Cylinder
Collects percolated water over measured time intervals with 0.5 mL accuracy.
Vacuum De-Airing Water Tank
Removes dissolved gases from permeate water to prevent entrapped air bubbles in soil pores.
Laboratory Electronic Analytical Balance
Weighs collected effluent to verify volumetric discharge gravimetrically.
FOLLOW THE METHOD
A reason behind every step.
Determine the saturated hydraulic conductivity (K_sat) of agricultural soil cores using a constant-head permeameter and verify Darcy's linear filtration law. Standardized parameter settings: 0.5, 0.9, 1.3, 1.7, 2.1, 2.5 m/m.
01
Soil Core Preparation & Saturation
Trim the ends of the undisturbed soil core flush with the sample cylinder. Place the core in a vacuum saturator and slowly saturate from the bottom upward with de-aired water over 24 hours to eliminate entrapped air.
02
Permeameter Cell Assembly
Assemble the saturated core into the permeameter cell between fine mesh screens and saturated porous stones, tightening tie rods to seal against side-wall bypass leakage.
03
Constant-Head Gradient Setup
Connect the constant-head reservoir to establish an initial hydraulic head loss ΔH = 5.0 cm across the 10.0 cm core (gradient i = 0.50 m/m).
04
Steady Effluent Collection
Allow water to flow until effluent discharge reaches steady state, then collect water in a graduated cylinder over exactly 5.0 minutes, logging collected volume Q.
05
Gradient Stepping
Increment hydraulic head gradient in four stages up to i = 2.5 m/m (ΔH = 9.0, 13.0, 17.0, 21.0, 25.0 cm), collecting timed effluent for each gradient.
06
Darcy Velocity & K_sat Calculation
Calculate Darcy velocity v = Q / (A·Δt) (cm/min), plot v against hydraulic gradient i, and perform linear regression through the origin to determine K_sat.
YOUR NOTEBOOK · 0 OBSERVATIONS
Turn measurements into agricultural engineering insight.
Points are your recorded observations. The solid regression line validates Saturated Hydraulic Conductivity mathematical scaling.
LINEAR REGRESSION FIT · y = mx + b
v = K_sat · i = 0.1800 · i
| # | Hydraulic Head Gradient i = ΔH / L (m/m) | Darcy Discharge Velocity v (cm/min) | Hydraulic gradient i = ΔH / L (m/m) | Darcy velocity v (cm/min) | Remove |
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