diff --git a/fdm/visualizer.py b/fdm/visualizer.py
index 37e2334..6f245fa 100644
--- a/fdm/visualizer.py
+++ b/fdm/visualizer.py
@@ -1,5 +1,6 @@
 import sys
 import os
+from datetime import datetime
 import numpy as np
 import plotly.graph_objects as go
 
@@ -7,16 +8,6 @@ sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 import config
 
 BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
-FDM_ANIM_DIR = os.path.join(BASE_DIR, 'animations', 'fdm')
-
-
-def _next_path(base_dir, prefix, ext):
-    i = 1
-    while True:
-        path = os.path.join(base_dir, f'{prefix}_{i:03d}{ext}')
-        if not os.path.exists(path):
-            return path
-        i += 1
 
 
 def visualize_fdm(T_matrix, x_vals, t_vals):
@@ -31,7 +22,9 @@ def visualize_fdm(T_matrix, x_vals, t_vals):
     t_vals : np.ndarray, shape (NT,)
         Time values.
     """
-    os.makedirs(FDM_ANIM_DIR, exist_ok=True)
+    timestamp = datetime.now().strftime('%Y%m%d_%H%M%S')
+    out_dir = os.path.join(BASE_DIR, 'results', 'fdm', timestamp)
+    os.makedirs(out_dir, exist_ok=True)
 
     # ------------------------------------------------------------------
     # 1. Heatmap
@@ -66,7 +59,7 @@ def visualize_fdm(T_matrix, x_vals, t_vals):
         height=500,
     )
 
-    heatmap_path = _next_path(FDM_ANIM_DIR, 'heatmap', '.html')
+    heatmap_path = os.path.join(out_dir, 'heatmap.html')
     fig_heatmap.write_html(heatmap_path)
     print(f"Heatmap saved        → {heatmap_path}")
 
@@ -168,7 +161,7 @@ def visualize_fdm(T_matrix, x_vals, t_vals):
         frames=frames,
     )
 
-    anim_path = _next_path(FDM_ANIM_DIR, 'animation', '.html')
+    anim_path = os.path.join(out_dir, 'animation.html')
     fig_anim.write_html(anim_path)
     print(f"Animation saved      → {anim_path}")
 
@@ -222,6 +215,6 @@ def visualize_fdm(T_matrix, x_vals, t_vals):
         height=480,
     )
 
-    ts_path = _next_path(FDM_ANIM_DIR, 'time_series', '.html')
+    ts_path = os.path.join(out_dir, 'time_series.html')
     fig_ts.write_html(ts_path)
     print(f"Time-series saved    → {ts_path}")