Welcome! Thank you for posting the question to the forum and all of the files needed to examine the issue. A few answers below.
First, I imagine you have already seen the tests that use the same the method for the initial temperature (ascii profile):
initial temperature profile test prm file
1、 Initial temperature changes only at the bottom of the model, not throughout the model
To start, what you have implemented looks correct for the initial temperature.
subsection Initial temperature model
set Model name = ascii profile
subsection Ascii data model
set Data directory = /home/aspect/aspect/build/test-gravity/
set Data file name = temperature.txt
set Scale factor = 1
Likewise, the depth values in temperature.txt are consistent with your model geometry.
Request - can you also post the log.txt from your simulation to ensure that the correct temperature.txt is in fact being read? I can’t imagine it is not (an error should be thrown), but it would be good to check.
What appears to be happening is that the bottom and top temperatures are set from the boundary temperature model section, but the initial temperature values are not read in correctly.
Can you try the following:
Remove the initial topography from the simulation (flat upper boundary)? That may produce an issue, as the reference point for the starting depth is not constant in this model. However, I would have expected a different issue to arise.
See what happens when the boundary temperatures are set by the initial conditions via?:
subsection Boundary temperature model
set Fixed temperature boundary indicators = bottom, top
set List of model names = initial temperature
I’m not sure if P represents pressure, and if so, why does it have a positive value. Normally, at surface pressure is zero.
p represents pressure. I think what you must be seeing is entirely some sort of dynamic effect (what does flow field look like?), as you have a normal value of gravity (9.8), but the material properties are those that would normally be used for a nondimensional simulation:
subsection Gravity model
set Model name = vertical
set Magnitude = 9.8
subsection Material model
set Model name = simple
subsection Simple model
set Reference density = 1
set Reference specific heat = 1
set Reference temperature = 0
set Thermal conductivity = 1
set Thermal expansion coefficient = 1
set Viscosity = 1
To summarize, I think there may be a combination of factors producing the odd results.
A suggestion - I would try starting from this example, and piece by piece change the model design (initial temperature, geometry, etc) towards your desired model design. After changing each parameter, rerun the model to make sure it is behaving in the expected manner: