# Laplace Law, multiComponent2d, SC model

Hello, everyone! I am new in Palabos. I met a problem that I couldn’t solve，so I came to the forum to ask for help.

I’ve recently been testing Laplace’s law, which states that the pressure difference between inside and outside the droplet is inversely proportional to the radius. My model is as follows (based on the Palabos multiComponent2d model) : place a droplet with radius R in the center of the grid of 100*100, the density of droplet and air are 2 (lattice units) respectively, the dissolution density of droplet and air are 1.e-5. Periodic boundary conditions are used in the model, and the initial velocity is 0. ForcedShanchenD2Q9 model is used, but the force is set to 0. Set different radius values R: 14, 16, 16.4, 17, 18, 19, 20, 22, 24. Set the pressure calculation area (R-9, R-7) and (R+7, R+9). Through data statistics, I found that the linear relationship was satisfied only when R=14, 16, 18, 20, the slope coefficient is 0.31 and intercept term is 0.00661. Neither odd nor decimal numbers conform to the rule. My data is as follows.

I want to know why R=14,16,18,20 satisfy the requirement, but all the other odd and decimal numbers don’t fit the rule. Thank you very much!