1d_fd_simple_shear.1 (7350B)
1 .Dd $Mdocdate$ 2 .Dt 1D_FD_SIMPLE_SHEAR 1 3 .Os 4 .Sh NAME 5 .Nm 1d_fd_simple_shear 6 .Nd simulate granular flows with pore-pressure dynamics 7 .\" .Sh LIBRARY 8 .\" For sections 2, 3, and 9 only. 9 .\" Not used in OpenBSD. 10 .Sh SYNOPSIS 11 .Nm 12 .Op Fl A Ar grain-nonlocal-ampl 13 .Op Fl a Ar fluid-pressure-ampl 14 .Op Fl b Ar grain-rate-dependence 15 .Op Fl C Ar fluid-compressibility 16 .Op Fl c Ar grain-cohesion 17 .Op Fl D Ar fluid-diffusivity 18 .Op Fl d Ar grain-size 19 .Op Fl e Ar end-time 20 .Op Fl F 21 .Op Fl f Ar applied-shear-friction 22 .Op Fl g Ar gravity-accel 23 .Op Fl H Ar fluid-pressure-phase 24 .Op Fl h 25 .Op Fl I Ar file-interval 26 .Op Fl i Ar fluid-viscosity 27 .Op Fl K Ar dilatancy-constant 28 .Op Fl k Ar fluid-permeability 29 .Op Fl L Ar length 30 .Op Fl l Ar applied-shear-vel-limit 31 .Op Fl m Ar grain-friction 32 .Op Fl N 33 .Op Fl n Ar normal-stress 34 .Op Fl O Ar fluid-pressure-top 35 .Op Fl o Ar origo 36 .Op Fl P Ar grain-compressibility 37 .Op Fl p Ar grain-porosity 38 .Op Fl q Ar fluid-pressure-freq 39 .Op Fl R Ar fluid-density 40 .Op Fl r Ar grain-density 41 .Op Fl S Ar fluid-pressure-pulse-shape 42 .Op Fl s Ar applied-shear-vel 43 .Op Fl T 44 .Op Fl t Ar curr-time 45 .Op Fl U Ar resolution 46 .Op Fl u Ar fluid-pulse-time 47 .Op Fl V Ar bot-vel 48 .Op Fl v 49 .Op Fl Y Ar max-porosity 50 .Op Fl y Ar min-porosity 51 .Op name 52 .Sh DESCRIPTION 53 The 54 .Nm 55 utility simulates the coupled continuum dynamics of granular 56 deformation and pore pressure. The simulation space is one-dimensional 57 and undergoes confined, simple shear at a pretedermined velocity 58 or friction ratio. The effective stress is modulated by pore-pressure 59 dynamics when fluid dynamics are enabled. 60 .Pp 61 The arguments are as follows: 62 .Bl -tag -width Ds 63 .It Fl A Ar grain-nonlocal-ampl 64 Amplitude of granular non-locality [-] (default 0.4). 65 .It Fl a Ar fluid-pressure-ampl 66 Amplitude of fluid-pressure perturbations [Pa] (default 0). 67 Only relevant with fluid dynamics enabled 68 .Fl ( F ) . 69 .It Fl b Ar grain-rate-dependence 70 Granular rate dependence beyond yield [-], (default 0.9377). 71 .It Fl C Ar fluid-compressibility 72 Fluid adiabatic compressibility [Pa^-1] (default 3.9e-10). 73 Only relevant with fluid dynamics enabled 74 .Fl ( F ) . 75 .It Fl c Ar grain-cohesion 76 Granular material cohesion [Pa] (default 0). 77 .It Fl D Ar fluid-diffusivity 78 Fluid diffusion coefficient [m^2/s] (default -1). Overrides fluid 79 permeability (-k), grain compressibility (-P), fluid compressibility 80 (-C), and fluid viscosity (-i). Do not use for transient simulations 81 (-T). Disabled when set to a negative value. 82 .It Fl d Ar grain-size 83 Granular material representative grain size [m] (default 0.04). 84 .It Fl e Ar end-time 85 Simulation end time [s] (default 1). 86 .It Fl F 87 Enable pore-space fluid dynamics. 88 .It Fl f Ar applied-shear-friction 89 Applied ratio between shear stress and normal stress at the top 90 boundary [-] (default 0.45), overridden by 91 .Fl s 92 and 93 .Fl l 94 if these are set. 95 .It Fl g Ar gravity-accel 96 Gravity magnitude [m/s^2] (default 9.81). 97 .It Fl H Ar fluid-pressure-phase 98 Phase of fluid-pressure perturbations [s] (default 0). 99 Only relevant with fluid dynamics enabled 100 .Fl ( F ) . 101 .It Fl h 102 Show usage information. 103 .It Fl I Ar file-interval 104 Simulation time interval between writing output to disk [s] (default 105 1.0). 106 .It Fl i Ar fluid-viscosity 107 Fluid dynamic viscosity [Pa*s] (1.787e-3). 108 Only relevant with fluid dynamics enabled 109 .Fl ( F ) . 110 .It Fl K Ar dilatancy-constant 111 Factor relating dilatancy and shear stress [TODO] (default 1.0). 112 Only relevant with transient granular dynamics enabled 113 .Fl ( T ) . 114 .It Fl k Ar fluid-permeability 115 Darcian intrinsic permeability of granular material [m^2] (default 116 1.9e-15). 117 Only relevant with fluid dynamics enabled 118 .Fl ( F ) . 119 .It Fl L Ar length 120 Simulation domain length [m] (default 1). 121 .It Fl l Ar applied-shear-vel-limit 122 Upper limit to modeled shear velocity [m/s] (default nan), overrides 123 .Fl f 124 and 125 .Fl s . 126 .It Fl m Ar grain-friction 127 Grain friction coefficient [-] (default 0.404026). 128 .It Fl N 129 Normalize output velocities to the range [0;1]. 130 .It Fl n Ar normal-stress 131 Normal stress applied at the top boundary [Pa] (default 120e3). 132 .It Fl O Ar fluid-pressure-top 133 Fluid pressure applied at the top boundary [Pa] (default 0). 134 Only relevant with fluid dynamics enabled 135 .Fl ( F ) . 136 .It Fl o Ar origo 137 Simulation domain origo [m] (default 0). 138 .It Fl P Ar grain-compressibility 139 Granular material compressibility [Pa^-1] (default 1e-8). 140 .It Fl p Ar grain-porosity 141 Granular material porosity [-] (default 0.25). 142 .It Fl q Ar fluid-pressure-freq 143 Frequency of fluid-pressure perturbations [s^-1] (default 1). 144 Only relevant with fluid dynamics enabled 145 .Fl ( F ) . 146 .It Fl R Ar fluid-density 147 Fluid density [kg/m^3] (default 1000). 148 Only relevant with fluid dynamics enabled 149 .Fl ( F ) . 150 .It Fl r Ar grain-density 151 Granular material density [kg/m^3] (default 2600). 152 .It Fl S Ar fluid-pressure-pulse-shape 153 Shape of pulse perturbations in fluid pressure at the top boundary. 154 Valid options are 155 .Ar triangular 156 (default) or 157 .Ar square . 158 Only relevant with fluid dynamics enabled 159 .Fl ( F ) . 160 .It Fl s Ar applied-shear-vel 161 Shear the material under constant velocity [m/s] instead of a friction value. 162 Overrides 163 .Fl f 164 and is overridden by 165 .Fl l . 166 .It Fl T 167 Enable transient granular properties. 168 .It Fl t Ar curr-time 169 Simulation start time [s] (default 0). 170 .It Fl U Ar resolution 171 Numerical resolution of simulation domain [-] (default nan). If 172 not set, the cell size equals the grain size. 173 .It Fl u Ar fluid-pulse-time 174 Time of fluid-pressure pulse peak [s] (default nan). 175 Only relevant with fluid dynamics enabled 176 .Fl ( F ) . 177 .It Fl V Ar bot-vel 178 shear velocity at base [m/s] (default 0). 179 .It Fl v 180 Show version information. 181 .It Fl Y Ar max-porosity 182 Granular material porosity [-] at inertia number I=1 in transient 183 simulations 184 .Fl ( T ) 185 (default 0.55). 186 .It Fl y Ar min-porosity 187 Minimum granular material porosity [-] in transient simulations 188 .Fl ( T ) 189 (default 0.20). 190 .Pp 191 .El 192 The final simulation state is written to stdout, see 193 .Sx OUTPUT FORMAT 194 for a description of the data format. 195 .Sh OUTPUT FORMAT 196 The output consists of the following tab-delimited fields, with one 197 row per cell in the simulation domain: 198 .Pp 199 .Bl -enum -compact 200 .It 201 position [m] 202 .It 203 shear velocity [m/s] 204 .It 205 effective normal stress [Pa] 206 .It 207 fluid pressure [Pa] 208 .It 209 friction [-] 210 .It 211 shear strain rate [-] 212 .It 213 porosity [-] 214 .It 215 inertia number [-] 216 .It 217 shear stress [Pa] 218 .El 219 .Sh FILES 220 If 221 .Ar name 222 is set, the simulation state is written to files in the current 223 directory named in the format 224 .Pa <name>.outputDDDDD.txt . 225 Here, DDDDD is a integer counter starting from 00000, and incrementing 226 by 1 for each new file. Each file contains the state at a single 227 point in simulation time. The output format is specified in the 228 section 229 .Sx OUTPUT FORMAT , 230 and output files are generated with the interval specified with 231 .Fl I Ar file-interval . 232 .Sh EXIT STATUS 233 .Nm 234 exits 0 on success, and >0 if a runtime error occurs: 235 .Pp 236 .Bl -tag -compact 237 .It 0 238 successful exit 239 .It 1 240 unspecified error 241 .It 2 242 .Xr pledge 2 243 error (OpenBSD only) 244 .It 10 245 transient solver error 246 .It 11 247 fluid solver error 248 .It 12 249 granular solver error 250 .It 20 251 time step error 252 .El 253 .\" .Sh EXAMPLES 254 .\" .Sh DIAGNOSTICS 255 .\" For sections 1, 4, 6, 7, 8, and 9 printf/stderr messages only. 256 .\" .Sh ERRORS 257 .\" For sections 2, 3, 4, and 9 errno settings only. 258 .Sh SEE ALSO 259 .Xr max_depth_simple_shear 1 260 .Xr shear_flux 1 261 .Sh AUTHORS 262 .An Anders Damsgaard Aq Mt anders@adamsgaard.dk