<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Dear PyLith Developers:<br><br> I have a question about the viscosity_coefficient "eta", which is one of the physical properties that you get in the output "cel_info_fields" when you carry out analysis of a power-law viscoelastic material using PyLith 1.4.2.<br><br> I thought the values of "eta" could be calculated using the equations (5.74), (5.75) and (5.76) by substituting the power-law coefficient "At" and the power-law exponent n. I substituted "At"=1.99e-41 and n=3 into those equations, and obtained "eta"=1.77e+13 as a result. However, the value of "eta" in info.vtk file which was obtained as an automatic output of the PyLith program for the same values of "At"=1.99e-41 and n=3 was "eta"=1.77e+18, 100,000 times as large as the above value. By the way, the final output of the PyLith program coincided with the analytical solution.<br><br>I would like to find out the origin of this difference, so please kindly tell me how the value of "eta" is calculated within the PyLith program.<div><br></div><div><br></div><div>------------------------------------------------------<br>Yuta ABE<br>Active Fault and Earthquake Reserch Center<br>National Institute of Advanced Industrial Science and Technology,Japan<br>tel; +81-29-861-3686<br>email; <a href="mailto:y-kuwahara@aist.go.jp">yuta-abe@aist.go.jp</a><br><div>------------------------------------------------------- </div></div></body></html>