Mechanisms of Heat Transferīy default when creating a new project, Flow Simulation simulates heat transfer in fluids and performs a steady-state analysis.
#Solidworks flow simulation transient natural convection full#
External analyses represent a larger computational domain, such as a room full of air around the product to be analyzed. Internal analyses represent closed wall systems such as electronics enclosures, or a piping system or manifold. Transient analysis makes it possible to input curves for conditions such as heat sources to represent duty cycle, or analyze problems which may be constantly fluctuating and have no steady-state solution at all.Īnalysis can be internal or external. Transient analysis is enabled via the time-dependent checkbox in the Project Wizard, which iterates over physical time steps and stores results over the time history of the solution, at the cost of extended solution time. By default, new projects are treated as steady-state. Steady-state and transient calculations can be performed. The appropriate definition of goals is thereby crucial to ensuring accuracy and reasonable computation time. In other words, the solver continues to iterate until the values of the goals flatten off, indicating that the system has reached steady-state equilibrium. In the case of steady-state analysis, the convergence of goals is tracked and utilized as a stopping criteria for the solver. Key parameters of interest are tracked during the solution by the creation of user-defined goals. The computational domain is broken up into a Cartesian mesh, a grid-like mesh made up of box-shaped cells, which will be discussed later in this article. Background & Terminologyįlow Simulation is a computational fluid dynamics (CFD) analysis package using the finite volume method. This article will examine the use cases of SOLIDWORKS Flow Simulation as it relates to thermal analysis, with a specific focus on predicting the performance of electronics cooling systems. The ability to simulate heat conduction combined with convective heat transfer generated by airflow over heatsinks and chip packages offers a high degree of confidence in temperatures predicted, especially when compared to traditional hand calculations or FEA-based thermal analysis where assumptions about airflow must be input in the form of convection coefficients. One of the most common applications of Flow Simulation today though is thermal analysis for predicting cooling performance of electronics and other heat generating components. Because it is a general-purpose fluid dynamics analysis package, Flow Simulation can analyze a wide variety of problems, including: aerodynamic and hydrodynamic problems such as pump and propeller design, head loss in piping systems and coefficient of drag calculations for vehicles. Many handbooks contain tabulated values of the convection heat transfer coefficients for different configurations.SOLIDWORKS Flow Simulation is a powerful, general-purpose CFD package integrated directly into the SOLIDWORKS CAD environment. Measuring a temperature gradient across a boundary layer requires high precision and is generally accomplished in a research laboratory. Thus the convection coefficient for a given situation can be evaluated by measuring the heat transfer rate and the temperature difference or by measuring the temperature gradient adjacent to the surface and the temperature difference. The actual mechanism of heat transfer through the boundary layer is taken to be conduction, in the y-direction, through the stationary fluid next to the wall being equal to the convection rate from the boundary layer to the fluid. A Prandtl Number (Pr) of 1 would imply the same behavior for both boundary layers.
Fluid properties that make up the Prandtl Number govern the relative magnitude of the two types of boundary layers. Notice that the thermal boundary layer thickness is not necessarily the same as that of the fluid. A schematic of the temperature variation is shown in the next figure. A similar sketch could be made of the temperature transition from the temperature of the surface to the temperature of the surroundings.