Failed to evaluate variable- comp1.ht.Tinit

Hello,

Please I am working at simulating a 3D solar panel in COMSOL 5.1. After successfully fixing the errors on the mesh and the physics have been added, I proceed to compute the study, and I got the following error:

Failed to evaluate operator.
- Operator: mean
- Geometry: geom1
- Boundaries: 33, 34, 35, 36
Mean operator requires an adjacent entity of higher dimension.
Failed to evaluate expression.
- Expression: mean(comp1.ht.Tinit)
Failed to evaluate variable.
- Variable: comp1.ht.Tinit
- Geometry: geom1
- Boundaries: 33, 34, 35, 36
Failed to evaluate variable.
- Variable: comp1.ht.Jinit
- Defined as: (((comp1.ht.feb(comp1.ht.Tinit/unit_K_cf)*unit_W_cf)*comp1.ht.epsilon_rad)/(unit_m_cf^2))+((1-comp1.ht.epsilon_rad)*comp1.ht.e_bamb)
Failed to evaluate expression.
- Expression: comp1.ht.Jinit
- Feature: Dependent Variables 1 (sol1/v1)

Please I would appreciate if anyone out there can help me with 'Tips' to solve this problem.

Kind regards,
Samuel