Hi,
In transient thermal simulation, several ways of defining initial temperatures distribution are available (as detailed in the Manual, section 2.8.2.5). In your case, either 'steady state' or 'continue simulation' can allow you to avoid those 30 min with no EM sources. Here an example of process:
(1) Run a first thermal simulation with only the human model and its proper thermal features, until reaching the required steady-state. This simulation would be the initialization of all your thermal simulations.
(2) Create a 2nd simulation in which the 'Material' is defined as for the first one and use the 'Continue Simulation' option. You would also need to define the 'Snapshot', meaning at what time of the first simulation you are considering the initial temperatures (take care in case of non-convergence). EM sources can then be directly applied at 0 second.
For ensuring accuracy, I would advice you to keep the same grid for all your thermal simulations.
Best,
Mélina

Dear Farima,
you can use Python scripts to do that quickly and precisely. The first thing to do is to write a script that sample N=100 (x,y) coordinates within the radius of the cylinder according to a distribution that you want (random, uniform, etc.). Then you can create trajectories as polylines for each sampled point. Something like that:

import s4l_v1 as s4l import numpy as np from s4l_v1 import Vec3 R=10 # Radius (mm) Z=100 # length of the cylinder (mm) N=100 # N axons ## Creates a folder in the Model Panel folder=s4l.model.CreateGroup('Axon Trajectories') points=[] cnt=0 while cnt<N: # Creates Randomly Distributed Points x=2*R*(-0.5+np.random.rand()); y=2*R*(-0.5+np.random.rand()) if (x*x+y*y<R*R): axon=s4l.model.CreatePolyLine([Vec3(x,y,-0.5*Z),Vec3(x,y,+0.5*Z)]) axon.Name='Axon_'+str(cnt) folder.Add(axon) cnt+=1

Hi, Have you tried to run this simulation as "Single FDTD", instead of "Multiport"? You can convert from one type to the other by right-clicking on the simulation and choosing "Clone As" -> "Single FDTD".
I am not sure Multiport simulations have support for waveguide sources (and you have only one such source, so Single FDTD should anyway be what you need).

Next to the "Statistics"-button you can see a "Viewers"-button, which has a wide variety of options on how to visualize your data. It includes slice viewers where you can see the SAR-distribution of an arbitrary plane, a histogram plot option, and much more.

Dear Sim4Life developers,
I have came across the same problem and cannot update materials database due to the Russian words within a pathway.
Is it possible to solve this problem by directing Sim4Life to search for materials in another pathway?

Thank you a lot in advance,
Valeriia

Have you found an answer to your question already? If not, I would encourage you to read the corresponding sections in Sim4Life's user manual:
2.8.2 Thermal Simulation Settings
2.5.1.1.2 Numerical Stability (this is in the FDTD section, but the same criteria apply in the thermal solver)

If there is a message such as "Job Finished", this probably means that the job is not really "stuck" at 0% but that it simply failed, for some reason. You might get additional information by looking at the Console (View -> Console) or by looking at the log file from the solver itself (this is a file ending with _Input.log in the Results folder of the project). The latter is also visible from within Sim4Life using the Task Manager (click at the bottom right of Sim4Life to open it).

That solved the problem, thank you very much!