COMPARISION OF GEARSLOSHING EFFECT BY WATER AND OIL FOR GEAR WITH AND WITHOUT INCREASED CLEARANCE

Objective:

To do a gearbox sloshing effect using with clearance and without clearance using water and oil.

Preprocessing:

Since we are using student version, there must be a mesh limit. So convert the 3d case into 2d cases.

Similarly we will do for the gear with increased clearance.

Meshing:

The above figure shows the meshing settings used for this analysis.

Since we are running dynamic simulation. Creation of mesh element is very important. During the gear moving, there is a chance of floating point exception error shown and also there is chance of neagtive cell volume. This all depends on time step. Time step depends on the length of the element. So selecting the mesh size is necessary in order to get the perfect result.

Solver:

This analysis, we are using pressure based solver and transient simulation. Because we want to know how the gearsloshing effect is happening for the water and the oil for both gear with and without increased clearance.

Since only bottom half portion covered with the lubricant. So we use the adapt cell option to define the mesh element.

Since it is dynamic case we use the c coding to define the rotation. VOF and multiphase model is used to run the simulation.

Red area indicate the lubricant and blue is air.

Whenever i got error, dynamic meshing and timestep changed in order to get the result. Time step here i am using very smal 1e-5.

Solution:

Without Clearance with water:

Without Clearance with Oil

Increased clearance with water

Increased clearance with oil

The above animation shows the gear sloshing effect for both the geometry by using water and oil.

We will compare the gearsloshing effect by water and oil without increased clearance. If we observe clearly, it will shows the difference. Water has less viscosity compared to the oil. When gear rotate, the oil stitch with the gear more compare to water. When the gear rotates heat generated and also there is a chance of material failure. From this analysis oil have more efficient lubricant compare to the water.

Now we will compare the result for the increased clearance. Here also oil have more efficient compare to the water.

Conclusion:

Clearances based on the application. Here Oil have the more efficient compare to the water for both the cases.

But from the application increased clearance with oil have more efficient compare to the water.