fix initial condition sanity check

TurTLE/DNS.py

@@ -1048,14 +1048,7 @@ class DNS(_code):
         # take care of fields' initial condition
         # first, check if initial field exists
         need_field = False
-        if self.dns_type in [
-                'NSVE',
-                'NSVE_no_output',
-                'static_field',
-                'NSVEparticles',
-                'NSVEcomplex_particles',
-                'NSVEparticles_no_output',
-                'NSVEp_extra_sampling']:
+        if self.check_current_vorticity_exists:
             if not os.path.exists(self.get_checkpoint_0_fname()):
                 need_field = True
             else: