Merge pull request #283 from jdegraaf/master

ENGINE feature: corrected problems with the parsing of v_swim, which …

src/core/lb.cpp

@@ -2848,9 +2848,9 @@ inline void lb_viscous_coupling(Particle *p, double force[3]) {
 #ifdef ENGINE
   if ( p->swim.swimming )
   {
-    velocity[0] -= p->swim.v_swim*p->r.quatu[0];
-    velocity[1] -= p->swim.v_swim*p->r.quatu[1];
-    velocity[2] -= p->swim.v_swim*p->r.quatu[2];
+    velocity[0] -= (p->swim.v_swim*time_step)*p->r.quatu[0];
+    velocity[1] -= (p->swim.v_swim*time_step)*p->r.quatu[1];
+    velocity[2] -= (p->swim.v_swim*time_step)*p->r.quatu[2];
     p->swim.v_center[0] = interpolated_u[0];
     p->swim.v_center[1] = interpolated_u[1];
     p->swim.v_center[2] = interpolated_u[2];

src/core/lbgpu_cuda.cu

@@ -1653,9 +1653,9 @@ __device__ void calc_viscous_force_three_point_couple(LB_nodes_gpu n_a, float *d
   interpolation_three_point_coupling(n_a, position, node_index, d_v, delta, interpolated_u);
 
 #ifdef ENGINE
-  velocity[0] -= particle_data[part_index].swim.v_swim*particle_data[part_index].swim.quatu[0];
-  velocity[1] -= particle_data[part_index].swim.v_swim*particle_data[part_index].swim.quatu[1];
-  velocity[2] -= particle_data[part_index].swim.v_swim*particle_data[part_index].swim.quatu[2];
+  velocity[0] -= (particle_data[part_index].swim.v_swim*para.time_step)*particle_data[part_index].swim.quatu[0];
+  velocity[1] -= (particle_data[part_index].swim.v_swim*para.time_step)*particle_data[part_index].swim.quatu[1];
+  velocity[2] -= (particle_data[part_index].swim.v_swim*para.time_step)*particle_data[part_index].swim.quatu[2];
 
   // The first three components are v_center, the last three v_source
   // Do not use within LB, because these have already been converted back to MD units
@@ -1948,9 +1948,9 @@ __device__ void calc_viscous_force(LB_nodes_gpu n_a, float *delta, float * partg
   interpolation_two_point_coupling(n_a, position, node_index, mode, d_v, delta, interpolated_u);
 
 #ifdef ENGINE
-  velocity[0] -= particle_data[part_index].swim.v_swim*particle_data[part_index].swim.quatu[0];
-  velocity[1] -= particle_data[part_index].swim.v_swim*particle_data[part_index].swim.quatu[1];
-  velocity[2] -= particle_data[part_index].swim.v_swim*particle_data[part_index].swim.quatu[2];
+  velocity[0] -= (particle_data[part_index].swim.v_swim*para.time_step)*particle_data[part_index].swim.quatu[0];
+  velocity[1] -= (particle_data[part_index].swim.v_swim*para.time_step)*particle_data[part_index].swim.quatu[1];
+  velocity[2] -= (particle_data[part_index].swim.v_swim*para.time_step)*particle_data[part_index].swim.quatu[2];
 
   // The first three components are v_center, the last three v_source
   // Do not use within LB, because these have already been converted back to MD units

src/core/thermostat.hpp

@@ -214,7 +214,7 @@ inline void friction_thermo_langevin(Particle *p)
   for (int i = 0; i < 3; i++) {
     velocity[i] = p->m.v[i];
 #ifdef ENGINE
-    velocity[i] -= p->swim.v_swim*p->r.quatu[i];
+    velocity[i] -= (p->swim.v_swim*time_step)*p->r.quatu[i];
 #endif
   }
 

src/tcl/particle_data_tcl.cpp

@@ -176,13 +176,13 @@ void tclcommand_part_print_swimming(Particle *part, char *buffer, Tcl_Interp *in
 #if defined(LB) || defined(LB_GPU)
   sprintf(buffer, " swimming %s %f %f %d %f %f",
       part->swim.swimming?"on":"off",
-      part->swim.v_swim/time_step, part->swim.f_swim,
+      part->swim.v_swim, part->swim.f_swim,
       part->swim.push_pull, part->swim.dipole_length,
       part->swim.rotational_friction);
 #else
   sprintf(buffer, " swimming %s %f %f %s %s %s",
       part->swim.swimming?"on":"off",
-      part->swim.v_swim/time_step, part->swim.f_swim,
+      part->swim.v_swim, part->swim.f_swim,
       "n/a", "n/a", "n/a");
 #endif
 }
@@ -1493,8 +1493,6 @@ int tclcommand_part_parse_swimming(Tcl_Interp *interp, int argc, char **argv,
       } else if ( p.swim.f_swim > 0.0 || p.swim.f_swim < 0.0 ) {
         printf("You can't set v_swim and f_swim at the same time!\n");
         return TCL_ERROR;
-      } else {
-        p.swim.v_swim *= time_step;
       }
     } else if ( ARG_IS_S(*change,"f_swim") ) {
       if ( !ARG_IS_D(++(*change),p.swim.f_swim) ) {