Dear Shah,

Before performing any new research in CFD, validation is necessary either it is from numerical or experimental data but experimental data is highly recommended.

Since you are working for the flow past circular cylinder, therefore numerous work have already published in journals so it easier for your validation.

The following test should perform before any research in order to optimize the computational time.

1) Domain Independent Test.

2) Grid Independent Test.

3) Time step size test.

In this you compare your result with the published work, for this you can select the following parameter:

1) Drag Coefficient.

2) Lift Coefficient.

3) Nusselt No.

4) Strouhal Number.

The first three if you are working in the field of Heat transfer and Aerodynamic Characteristic while the last one for the vortex shedding characteristic which is also dependent to the frequency of lift force.

Regards

Wali