Different solvers used in the Celsius and PowerDC tools for thermal simulations

Celsius Solvers:

There are three thermal solutions available in Celsius tool:

• Solid Objects Simulation for 3D Structures
• Solid Objects Simulation for Layered Structures
• Fluid Flow Simulation
   

Solid Objects Simulation for 3D Structures has a real 3D solver that uses FEM. Here, all objects will mesh as a 3D model and get solved. The 3D solid object geometries can either be created or can be imported from external files.

Solid Objects Simulation for Layered Structures has a layered structure solver that uses 2.5D FEM. It is mainly used to get fast simulation results for very large and complex PKG and PCB designs.

Fluid Flow Simulation has a real 3D solver that uses Finite Volume Method (FVM) to solve Navier-Stokes equations for analyzing the heat transfer between solids and the external flows in the fluid areas of the design.

PowerDC Solver:

In PowerDC, the thermal analysis will consider all objects like etch, copper, medium layer, via, wirebond, solder ball, bump, and so on. Some objects are in 3D mesh, and others are in 2.5D.

By default, shape/via/trace are handled in 2D but bump/ball/die/molding compound are handled in 3D.

There are options to control some objects to mesh in 3D, like a via (Enable 3D via model), for more detail, click here.