From ed1123f20f45158bfb2d44479b0b940a5efa8c8c Mon Sep 17 00:00:00 2001 From: nilsberglund-orleans <83530463+nilsberglund-orleans@users.noreply.github.com> Date: Tue, 27 Jul 2021 18:56:02 +0200 Subject: [PATCH] Add files via upload --- Parameters.md | 160 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 160 insertions(+) create mode 100644 Parameters.md diff --git a/Parameters.md b/Parameters.md new file mode 100644 index 0000000..a1c6925 --- /dev/null +++ b/Parameters.md @@ -0,0 +1,160 @@ +### Parameter values for YouTube simulations ### + +Created by **Nils Berglund** and optimized by **Marco Mancini** + +C code for videos on YouTube Channel https://www.youtube.com/c/NilsBerglund + +Below are parameter values used for different simulations, as well as initial conditions used in +function animation. Some simulations use variants of the published code. The list is going to be +updated gradually. + +### 18 July - Refraction (and diffraction) through a raindrop ### + +**Program: wave_billiard.c** + +#define MOVIE 1 /* set to 1 to generate movie */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define NX 1280 /* number of grid points on x axis */ +#define NY 720 /* number of grid points on y axis */ + +#define XMIN -1.8 +#define XMAX 1.8 /* x interval */ +#define YMIN -1.0125 +#define YMAX 1.0125 /* y interval for 9/16 aspect ratio */ + +#define JULIA_SCALE 1.0 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 3 /* choice of domain shape */ + +#define D_RECTANGLE 0 /* rectangular domain */ +#define D_ELLIPSE 1 /* elliptical domain */ +#define D_STADIUM 2 /* stadium-shaped domain */ +#define D_SINAI 3 /* Sinai billiard */ +#define D_DIAMOND 4 /* diamond-shaped billiard */ +#define D_TRIANGLE 5 /* triangular billiard */ +#define D_FLAT 6 /* flat interface */ +#define D_ANNULUS 7 /* annulus */ +#define D_POLYGON 8 /* polygon */ +#define D_YOUNG 9 /* Young diffraction slits */ +#define D_GRATING 10 /* diffraction grating */ +#define D_EHRENFEST 11 /* Ehrenfest urn type geometry */ +#define D_DISK_GRID 12 /* grid of disks */ +#define D_DISK_HEX 13 /* haxagonl grid of disks */ +#define D_DISK_PERCOL 14 /* random grid of percolation type */ + +#define D_MENGER 15 /* Menger-Sierpinski carpet */ +#define D_JULIA_INT 16 /* interior of Julia set */ +#define D_MENGER_ROTATED 17 /* rotated Menger-Sierpinski carpet */ + +/* Billiard tables for heat equation */ + +#define D_ANNULUS_HEATED 21 /* annulus with different temperatures */ +#define D_MENGER_HEATED 22 /* Menger gasket with different temperatures */ +#define D_MENGER_H_OPEN 23 /* Menger gasket with different temperatures and larger domain */ +#define D_MANDELBROT 24 /* Mandelbrot set */ +#define D_JULIA 25 /* Julia set */ +#define D_MANDELBROT_CIRCLE 26 /* Mandelbrot set with circular conductor */ + +#define LAMBDA 0.75 /* parameter controlling the dimensions of domain */ +#define MU 0.025 /* parameter controlling the dimensions of domain */ +#define NPOLY 8 /* number of sides of polygon */ +#define APOLY 1.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 1 /* set to 1 to replace hardcore boundary by medium with different speed */ + +#define OMEGA 0.9 /* frequency of periodic excitation */ +#define COURANT 0.01 /* Courant number */ +#define COURANTB 0.003 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMA_BC 1.0e-4 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_BC 5.0e-4 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +/* Boundary conditions */ + +#define B_COND 3 + +#define BC_DIRICHLET 0 /* Dirichlet boundary conditions */ +#define BC_PERIODIC 1 /* periodic boundary conditions */ +#define BC_ABSORBING 2 /* absorbing boundary conditions (beta version) */ +#define BC_VPER_HABS 3 /* vertically periodic and horizontally absorbing boundary conditions */ + +/* For debugging purposes only */ +#define FLOOR 0 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 9000 /* number of frames of movie */ +#define NVID 50 /* number of iterations between images displayed on screen */ +#define NSEG 100 /* number of segments of boundary */ +#define INITIAL_TIME 300 /* time after which to start saving frames */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ + +/* Plot type */ + +#define PLOT 1 + +#define P_AMPLITUDE 0 /* plot amplitude of wave */ +#define P_ENERGY 1 /* plot energy of wave */ +#define P_MIXED 2 /* plot amplitude in upper half, energy in lower half */ + + +/* Color schemes */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 1 /* choice of color scheme */ + +#define C_LUM 0 /* color scheme modifies luminosity (with slow drift of hue) */ +#define C_HUE 1 /* color scheme modifies hue */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 750.0 /* scaling factor for energy representation */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -220.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* Basic math */ + +#define PI 3.141592654 +#define DPI 6.283185307 +#define PID 1.570796327 + + +init_planar_wave(XMIN + 0.05, 0.0, phi, psi, xy_in); + +