diff --git a/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.cpp b/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.cpp
index 8c92568768..037b7be579 100644
--- a/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.cpp
+++ b/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.cpp
@@ -6,8 +6,8 @@ namespace SPH
 namespace fluid_dynamics
 {
 //=================================================================================================//
-FreeSurfaceWettingIndicationComplex::
-    FreeSurfaceWettingIndicationComplex(BaseInnerRelation &inner_relation,
+NonWettingSurfaceIndication::
+    NonWettingSurfaceIndication(BaseInnerRelation &inner_relation,
                                                BaseContactRelation &contact_relation, Real threshold, Real criterion)
     : FreeSurfaceIndicationComplex(inner_relation, contact_relation, threshold), wetting_criterion(criterion)
 {
@@ -17,9 +17,9 @@ FreeSurfaceWettingIndicationComplex::
     }
 }
 //=================================================================================================//
-FreeSurfaceWettingIndicationComplex::
-    FreeSurfaceWettingIndicationComplex(ComplexRelation &complex_relation, Real threshold, Real criterion)
-    : FreeSurfaceWettingIndicationComplex(complex_relation.getInnerRelation(),
+NonWettingSurfaceIndication::
+    NonWettingSurfaceIndication(ComplexRelation &complex_relation, Real threshold, Real criterion)
+    : NonWettingSurfaceIndication(complex_relation.getInnerRelation(),
                                                  complex_relation.getContactRelation(), threshold, criterion) {}
 
 //=================================================================================================//
diff --git a/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.h b/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.h
index 1884d32f1d..bed6605bfd 100644
--- a/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.h
+++ b/tests/user_examples/extra_src/shared/wetting_coupled_spatial_temporal_method.h
@@ -38,16 +38,19 @@ namespace SPH
 namespace fluid_dynamics
 {
 /**
- * @class WettingCoupledFreeSurfaceIndicationComplex
- * @brief indicate the interfacial fluid particles near the fluid-structure intersurface.
+ * @class NonWettingSurfaceIndication
+ * @brief Non wetting surface particles include free-surface ones and interfacial ones near the non-wetted structure.
+ * @brief Even the position divergence of interfacial fluid pariticles has satisfied with the threshold of spatial-temporal 
+   identification approach to be identified as internal ones,they will remain as free-surface ones if without 
+   any wetted neighboring solid particles.
  */
-class FreeSurfaceWettingIndicationComplex : public FreeSurfaceIndicationComplex
+class NonWettingSurfaceIndication : public FreeSurfaceIndicationComplex
 {
   public:
-    FreeSurfaceWettingIndicationComplex(BaseInnerRelation &inner_relation,
+    NonWettingSurfaceIndication(BaseInnerRelation &inner_relation,
                                                BaseContactRelation &contact_relation, Real threshold = 0.75, Real criterion = 0.99);
-    explicit FreeSurfaceWettingIndicationComplex(ComplexRelation &complex_relation, Real threshold = 0.75, Real criterion = 0.99);
-    virtual ~FreeSurfaceWettingIndicationComplex(){};
+    explicit NonWettingSurfaceIndication(ComplexRelation &complex_relation, Real threshold = 0.75, Real criterion = 0.99);
+    virtual ~NonWettingSurfaceIndication(){};
 
     inline void interaction(size_t index_i, Real dt = 0.0)
     {
@@ -94,7 +97,7 @@ class FreeSurfaceWettingIndicationComplex : public FreeSurfaceIndicationComplex
 };
 
 using WettingCoupledSpatialTemporalFreeSurfaceIdentificationComplex =
-    SpatialTemporalFreeSurfaceIdentification<FreeSurfaceWettingIndicationComplex>;
+    SpatialTemporalFreeSurfaceIdentification<NonWettingSurfaceIndication>;
 using SpatialTemporalFreeSurfaceIdentificationComplex =
     SpatialTemporalFreeSurfaceIdentification<FreeSurfaceIndicationComplex>;
 
diff --git a/tests/user_examples/test_2d_water_entry_exit/test_2d_water_entry_exit.cpp b/tests/user_examples/test_2d_water_entry_exit/test_2d_water_entry_exit.cpp
index 2fa2a345fe..f0e3967c9f 100644
--- a/tests/user_examples/test_2d_water_entry_exit/test_2d_water_entry_exit.cpp
+++ b/tests/user_examples/test_2d_water_entry_exit/test_2d_water_entry_exit.cpp
@@ -35,7 +35,7 @@ Real mu_f = 8.9e-7;                      /**< Water dynamics viscosity. */
 //----------------------------------------------------------------------
 //	Wetting parameters
 //----------------------------------------------------------------------
-Real diffusion_coff = 330.578 * pow(particle_spacing_ref,2); /**< Wetting coeffecient. */
+Real diffusion_coeff = 330.578 * pow(particle_spacing_ref,2); /**< Wetting coefficient. */
 Real fluid_moisture = 1.0;       /**< fluid moisture. */
 Real cylinder_moisture = 0.0;    /**< cylinder moisture. */
 Real wall_moisture = 1.0;        /**< wall moisture. */
@@ -166,7 +166,7 @@ class WettingCylinderBodyMaterial : public DiffusionReaction<Solid>
   public:
     WettingCylinderBodyMaterial() : DiffusionReaction<Solid>({"Phi"}, SharedPtr<NoReaction>(), rho0_s)
     {
-        initializeAnDiffusion<IsotropicDiffusion>("Phi", "Phi",diffusion_coff);
+        initializeAnDiffusion<IsotropicDiffusion>("Phi", "Phi",diffusion_coeff);
     };
 };
 using DiffusionCylinderParticles = DiffusionReactionParticles<SolidParticles, WettingCylinderBodyMaterial>;