Welcome to the User Interface video series.
This tutorial describes the one-dimensional functionality available in the GeoStudio mass and heat flow products,
SEEP/W, TEMP/W, CTRAN/W, and AIR/W.
Heat and mass flow in natural systems and laboratory experiments is often predominantly one-dimensional.
In such instances, it is convenient and computationally advantageous
to make use of the new one-dimensional analysis capabilities in GeoStudio.
Points and lines define the model geometry for a one-dimensional analysis. Thus, a project file may only contain points and lines instead of regions,
if all analyses in the project file are one-dimensional.
Alternatively, a project file may include multiple analyses with different dimensionality.
In this case, some analyses would be two-dimensional and comprise regions,
while other analyses are one-dimensional and defined by lines and points that are part of the regions from the 2D analyses.
The 1D functionality offers improved convergence and decreases the time required to solve an analysis.
In GeoStudio, the analysis dimension is set in the Define Analyses window.
In this demonstrative case, we have a project file with a two-dimensional water, heat, and gas transfer analysis.
I want to run a one-dimensional analysis of water, heat, and gas transfer along the right side of the defined domain.
To do so, I will clone the existing analysis,
rename it to reflect these changes,
and then modify the analysis dimension to 1D.
When changing from a 2D to 1D analysis, the materials and boundary conditions must be reassigned.
Let us do so by opening the Draw Materials window, and applying the materials to the lines along the right side of the 2D domain.
You will notice that in the Draw Materials window, we may only apply materials to lines for a 1D analysis.
We then must reapply the hydraulic, thermal, and gas boundary conditions to the surface point.
In the Draw Boundary Conditions window, I will change the selection option to points and select the hydraulic category.
Under this category, I will apply the LCI Penman Wilson boundary condition to the surface node.
Under the thermal category, I will apply the Surface Temperature boundary condition,
and under the gas category, I will apply the Atmospheric 02 Concentration.
At the bottom node we must reapply the thermal boundary condition with a constant temperature of 10°C.
A flux type boundary condition is by definition a volume, mass, or energy rate normalized by the flow area.
In a numerical analysis, the flux is integrated over the surface area to obtain nodal flow rates.
It may seem counterintuitive but in a 1D analysis we may apply a flux boundary condition to a point
despite the point not having any surface area in the drawing space.
This is possible in a 1D analysis because the domain is implicitly one unit wide by one unit thick in the out-of-plane direction.
After solving the 1D analysis, there are no contouring options available in the Results view.
However, the Draw Graph window provides comprehensive means of interpreting the modeled results.
If I select a plot, like the gas concentration profile along the right side of the domain,
I can easily click between the 2D and 1D analyses to compare the simulated results.
A two-dimensional analysis can simulate one-dimensional flow when the domain is comprised of a single column or row of elements.
However, the computational advantage of true one-dimensional numerical analysis may be significant for certain types of problems.
For example, simulations involving the land climate interaction or surface energy balance boundary conditions
are generally solved for a long duration, in many cases 20 to 30 years, using a two-hour time step.
The long durations and small time steps are necessary to consider climate effects over decades,
where hourly climate variability alters the ground conditions during the day.
The advantages of true 1D analyses are apparent when we consider a flow system
that is predominantly one-dimensional and computationally demanding.
The solve time for a true 1D analysis provides the base case for a comparison.
Switching from a 1D analysis to a 2D column that is a unit wide, causes the computation time to increase by a factor of 3.
When the 2D analysis width is increased to 10 elements, each a unit wide, the solve time is 8 times longer than the 1D scenario.
Finally, when the 2D analysis is 100 elements wide, the computation time is approximately 70 times greater.
This comparison demonstrates the motivation for 1D analyses.
In summary, one-dimensional modeling increases the functionality of the GeoStudio mass and heat flow products,
allowing for both 1D and 2D analyses within the same project file.
One-dimensional modeling assists with convergence and significantly decreases simulation solve times.
For more information on GeoStudio and its features, please look at the example files and other tutorial videos on the GEO-SLOPE website.
Thank you for watching.