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In no particular order

  1. Fine-tune or defend the turbulence model that is going to be used.
  2. Configure the barotropic model.

a. What type do we use? At the beginning just go with Linear b. What values do we use?

  1. Check the transport properties. The skeleton is already there

Suit them to our case. We could use CoolPROP to calculate the exact values.

  1. Initial conditions?

a What do we use for initial pressure? b And densisty? For liquid watter, 1000kg/m3 should be good enough.

  1. Refine the size of the problem and the bubble

Information on the decissions taken

Initial boundary conditions

  • The velocity is 0, we start from an “equilibrium”
  • The alpha of the liquid is 0, 1 for the bubble
  • The k value at t=0 is 0, since the U_avg is also 0 (we do not have turbulence at the beginning anywhere
  • Since k at t=0 is also 0, the values for epsilon, omega and nut are also 0
  • The initial Pressure and Temperature for the liquid are 100_000 [Pa] and 293 [K]
  • The initial pressure for the bubble will be 2000 [Pa]
  • The properties for the fluids are taken from the values above

Distance bubble centerPoint-wall

Source : https://www.youtube.com/watch?v=ZaB5B3pec-A

The inner world of a collapsing bubble, O.Supponen, P.Kobel, M.Farhat Ecole Polytechnique Federale de lausanne gamma = distance bubbleCenterPoint/ maxBubbleRadius = 1/0.56

for our case this resultet in the following Values

s = 0.0053571428 Rmax = 3e-3

Comments Ivan 31.05.2021

4a) -i asume we should calculate the pressure using the barotropic Compressibility model website(where i got the equation): https://caefn.com/openfoam/solvers-cavitatingfoam-v1812-barotropiccompressibilitymodel see figure inside figures folder

using the equation which i sent you in whatsapp we should by abel to calculate the right values.

b) if we assume isentropic phase change(during the initialization of the bubble), for standard Temeperature of 273.15 K the density would by 0.485 kg/ m³ (the calculated Presure should result ~ 6000 Pa (0.6kPa) . (approximatly).

PHD-Thesis: A Computational Study of the Inertial Collapse of Gas Bubbles Near a Rigid Surface by Shahaboddin Alahyari Beig

Based on the PHD-Tesis set up the following parameter:

R0 = 100mym = 100*e-6 m ~ we can disscuss the sourounding pressure value p0 = 5 MPa = 5*e6 Pa

numberofcells/initialbubbleRadius = 192, ~for the Thesis this resultet in approx 0.5 billiion cells

  1. & 5) i could do that if you could provide the DOI of the papaer which you mentioned is used also inside the lecture script