a-palyanov
commented
10 years ago Simulated elastic tissue elasticity coefficient, k = 3.84e-05 N/m r0 = 40 µm = 4e-5 m I've measured delta_r averaged over all elastic connections within simulated worm body shell in Sibernetic - it is equal to 0.01r0. Thus, P = (3.84e-05 N/m)(4e-7 m)/(4e-5 m)^2 = 0.0096 Pa. Actual pressure inside real C. elegans is estimated as 2–30 kPa. So, again a significant disagreement between simulation and reality (and at the same time the simulation looks so natural...) The problem with Young's modulus in reality and simulation has the same order (nearly 1:1e+06) . Calculations are described here: https://github.com/openworm/Smoothed-Particle-Hydrodynamics/issues/24
I've decided to consider a simple model of a 'spherical worm in vacuum' for better understanding of the problem (how to calculate pressure inside Sibernetic worm body model?). Liquid is almost incompressible, not only in reality, but in PCISPH simulation as well. So, pressure is caused not by liquid compression, but by elastic shell tension. I've performed some math and got the following formula for pressure:
r > r0 is caused by excess of liquid inside the worm.