In this workshop we will discuss timely and popular topics in internal combustion (IC) engine modeling and some of the unique features of CONVERGE that yield efficient and accurate simulations. Ever wonder why predicted cylinder quantities do not match the measured data when you think you have set up the case correctly? We will talk about what you need to consider when the predicted cylinder pressures do not agree with measurements and how to assess the accuracy of your input parameters. With optimized cell counts via Adaptive Mesh Refinement and fast flow and detailed chemistry solvers, you can extend your simulation domain to include multiple cylinders to analyze cylinder-to-cylinder variation, run multiple cycles to understand cycle-to-cycle variation, and capture propagating pressure waves to resolve engine knock. We will draw case setup recommendations from published works that use CONVERGE. *This lecture includes hands-on CONVERGE Studio practice.
CONVERGE and GT-SUITE can be coupled in a variety of ways. This workshop will discuss two coupling options. In conventional 1D-3D coupling, CONVERGE performs a 3D simulation while GT-SUITE performs a 1D simulation. The information at the interfaces is exchanged or mapped between the two programs. In hydromechanical coupling, you define a system with rigid bodies in GT-SUITE and subject the rigid bodies to fluid forces and constraints using CONVERGE. CONVERGE calculates the forces on the object and relays this information to GT-SUITE. GT-SUITE then solves the rigid body dynamics equations to update the object's state and sends this information back to CONVERGE. Finally, CONVERGE moves the object. *This lecture does not include hands-on CONVERGE Studio practice.
In this workshop we will introduce the topic of user-defined functions (UDFs) for CONVERGE. UDFs can be used to adjust existing models, implement new models, direct CONVERGE to calculate additional quantities, or initialize or reinitialize physical variables. *This lecture does not include hands-on CONVERGE practice.
Volume of fluid (VOF) methods are some of the most popular numerical techniques for locating moving and deforming interfaces between fluids in multiphase flow simulations. In this workshop we will discuss numerical details, example cases, and some validation calculations for the various VOF options in CONVERGE. One VOF method in CONVERGE is based on the species mass fraction equation and is appropriate for miscible or compressible multiphase flow calculations. One option in CONVERGE, which is based on the mass fraction VOF, is VOF-spray one-way coupling. In this option CONVERGE collects detailed fluid flow information near the nozzle exit during a VOF simulation and then uses this information to inject parcels for Lagrangian spray calculations. Another VOF method, which solves for the void fraction directly, is available in CONVERGE as two separate schemes: Piecewise-Linear Interface Calculation (PLIC) and High-Resolution Interface-Capturing (HRIC). These schemes have been tested on a range of problems including a breaking dam, a rising droplet, and spray injection, and each test case illustrates the ability of the method to track interfaces sharply. *This lecture includes hands-on CONVERGE Studio practice.
Rigid body fluid-structure interaction (FSI) modeling describes how the presence of one or more immersed objects affect the flow field and how the forces from the surrounding fluid influence the dynamics of the object. In this workshop we will discuss the theory behind FSI, the numerics of the dynamics solver, and the coupling of the dynamics solver to the flow solver in CONVERGE. We will consider several examples (a pressure relief valve, a spool valve, and an injector armature) that highlight the current capabilities of FSI modeling in CONVERGE. Finally, we will discuss complex examples that invoke a user-defined function coupled with FSI to model deforming bodies such as reed valve petals or a spring-close ball valve. *This lecture does not include hands-on CONVERGE Studio practice.
This workshop will introduce the concept of model optimization in CONVERGE. We will briefly discuss Genetic Algorithm optimization and Design of Experiments model interrogation. *This lecture does not include hands-on CONVERGE Studio practice.
CONVERGE includes a variety of tools to perform simplified kinetics calculations and to manipulate and evaluate chemical kinetic mechanisms. Zero-dimensional and one-dimensional calculators enable estimating the ignition delay and the flame speed of mixtures using specified kinetic mechanisms. The mechanism merge and reduction tools allow combining and decreasing the size of mechanisms to facilitate CFD chemistry calculations. This workshop will discuss the setup of these tools in CONVERGE Studio and strategies for effectively using them with CFD simulations. Participants will practice using the setup menus for the various modules. *This lecture includes hands-on CONVERGE Studio practice.
For several years CONVERGE has been able to interface with other software packages to model heat transfer in solids. Now CONVERGE can do both CFD and solid heat transfer modeling in the same simulation, which can simplify the process of predicting the temperatures in solids that are dependent on fluid interfaces, e.g., heads and valves in engines. This workshop will discuss conjugate heat transfer modeling in CONVERGE, including supercycling, which accounts for the disparate timescales in the solid and fluid domains by allowing the solid side of the simulation to progress with faster timescales than the fluid side of the simulation, and valve/seat contact resistance in engines, which is critical to accurate prediction of valve and head temperatures. *This lecture includes hands-on CONVERGE Studio practice.
Lunch will be provided.