diff --git a/tutorials/sphereGranFlow/RotaryAirLockValve/ReadMe.md b/tutorials/sphereGranFlow/RotaryAirLockValve/ReadMe.md
index ca952f4b..9284ec57 100644
--- a/tutorials/sphereGranFlow/RotaryAirLockValve/ReadMe.md
+++ b/tutorials/sphereGranFlow/RotaryAirLockValve/ReadMe.md
@@ -17,7 +17,7 @@ There is one type of particle in this blender. Particles are poured into the inl
 <img src="sample sample sample sample", width=700px>
 </div>
 <div align="center"><i>
-	particles are colored according to their velocity
+	particles are colored according to their id
 </div></i>
 </body>
 </html>
@@ -183,4 +183,4 @@ To perform simulations, enter the following commands one after another in the te
 Enter `$ particlesPhasicFlow` command to create the initial fields for particles.  
 Enter `$ geometryPhasicFlow` command to create the geometry.  
 At last, enter `$ sphereGranFlow` command to start the simulation.  
-After finishing the simulation, you can use  `$ pFlowtoVTK` to convert the results into vtk format stored in ./VTK folder.
\ No newline at end of file
+After finishing the simulation, you can use  `$ pFlowtoVTK` to convert the results into vtk format stored in ./VTK folder.