2phase-LBM-DNS

This project will reproduce the lattice Boltzmann method with DNS (direct numerical simulation) for the gas-solid two-phase flow using c language.

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1. File structure as follows:

+ CalcSolidConcentrationInterp
  - Calc20131129.m ---> Calculate the overlap area of the circle and square
  - dat.txt ---> results obained from the above program
  - ReadData.cpp ---> reading dat.txt and do bilinear interpolation
  - readme.txt ---> detailed description for files in this folder
+ LBMDNS.cpp ---> main program using c program
+ SolidConcentration.txt ---> solid concentration data
+ UnitConversion.py ---> a simple python tool to convert SI uint to lattice unit

2. Functions in LBMDNS.cpp:

+ void EsDataRead() ---> read solid concentration into ESMatrix
+ double EsInterp(double x,double y) ---> calculate solid concentration using bilinear interpolation
+ void SetLBMParameter() ---> D2Q9
+ double f_equ(double ux, double uy, double rho, int b) ---> calculate the value of the equilibrium distribution function
+ void init() ---> initialization for all parameters
+ Calc_IB() ---> check if interaction exists between the gas and particle phase, and record the particle number
+ void evolution() ---> evolution of LBM scheme, calculating the drag force and gas macro propeties at the same time (the force term uses He-Shan-Dollen model)
+ void ParticleMove() ---> calculate particle collision, at the same time refresh particle velocity and position
+ writefile_gas() ---> export the properties of the gas phase
+ writefile_particle() ---> export the properties of the particle phase