The DualHead infiltrometer measures soil saturated hydraulic conductivity, or Kfs. It is fully automated and requires no post-processing of data.
No Babysitting - Set it up and leave it to add water, maintain correct pressure heads, measure infiltration rates, and calculate K
Easy to Carry - Sized for one person to easily carry and install.
Simple Installation - Pound in the ring, connect the hoses, and set the parameters.
Run 3-4 Simultaneously - Designed and priced so you can account for spatial variability.
Eliminate "Guess Factor" - Measures infiltration at two different pressure heads to find (rather than estimating or guessing) the soil macroscopic capillary length factor (alpha).
Use Less Water - The DualHead uses air pressure to maintain the pressure heads. No need to adjust and measure water levels.
Proven Method - An automation of the method used by Reynods and Elrick (1990) and others.
How Does It Work?
Pound a ring into the soil, seal on the Infiltrometer Head, and connect the hoses to the control unit. Set up the test.
The Infiltrometer will pond water on top of the soil and use air pressure to create two different pressure heads. It will automatically maintain the correct water levels and will measure infiltration rates through two complete pressure cycles. The control unit collects all data and performs the calculations to determine field saturated hydraulic conductivity (Kfs).
All data can be downloaded from the control unit for further analysis.
Water flows through soil in three dimensions. In the early days of infiltrometers, it was simply impossible to solve two and three dimensional equations, so the dual ring infiltrometer was created to try to physically force water to flow in one dimension.
Now that we can do the math, the single ring infiltrometer is an easier--and better--method. However, if you're using a single head or a changing head, you still need to know--or guess--the "alpha factor" (soil macroscopic capillary length) to solve the equations.
Reynolds and Elrick (1990) showed that by solving the equations at two different pressure heads, alpha drops out, allowing you to determinesaturated hydraulic conductivity without making any assumptions.
|INFILTRATION RATE RANGE||0.0038 cm/hr to 115 cm/hr|
|INFILTRATION RATE RESOLUTION||0.0038 cm/hr|
|INFILTRATION RATE ACCURACY||±5 % of reading|
|Kfs||*(see explanation below)|
|WATER LEVEL||Maintained at 5 cm|
|PRESSURE HEAD RANGES||0 to 40 cm|
|OPERATING TEMPERATURE||0 to 50 ◦C|
|CHARGING ADAPTER||18 V 2.2 Amps; Range 18 to 24 V DC Output: USB|
|*The range of Kfs values that can be effectively measured by the DualHead Infiltrometer are limited by the minimum and maximum infiltration rates specified above. These depend not only on Kfs, but also on the pressure heads applied to the water during infiltration and to the 3-dimensional flow characteristics of the soil, so the mea- surement range of Kfs cannot be specified explicitly. The DualHead Infiltrometer will generally be able to make measurements on poorly to moderately structured soils as coarse as medium sand, but the maximum infiltration rate can be exceeded by soils with excessive structure and especially by soils with significant macropore flow.|