Macro Scale Casting Simulation with STAR-Cast J.Gnz CD-adapco - PowerPoint PPT Presentation

Macro Scale Casting Simulation with STAR-Cast J.Gänz – CD-adapco

Casting Systems • Product requirements increase: • Less weight • Higher efficiency • Time to market decreases • Casting processes must be adopted • Simulation to aide manufacturing goals • Understand and optimize the casting process • Enhance product quality • Rising demands require evolving simulation methods

Simulation Scope Physics System • Co-Simulation • Geometrical detail • Transient effects • Entire production process • Multi-Scale Simulation • Boundary Conditions Pouringsimulation; Courtesy of TiTal Macro to Micro-Scale Simulation using MICRESS

Counter Pressure Casting (CPC) Characteristics • Permanent mold process • Highly controllable process • Filling driven by applied pressure field Advantages of low pressure casting: • Smooth filling also for complex geometries • Dense microstructure (reduced porosity) • Improved material properties can reduce casting volume

Counter Pressure Casting Source: http://www.cpcmachines.com CPC-facility at the ACCESS- Techcenter

Counter Pressure Casting Fill the mold by increasing the pressure in the furnace chamber Source: http://www.cpcmachines.com

Counter Pressure Casting Let part solidify at high pressure to reduce porosity Source: http://www.cpcmachines.com

Counter Pressure Casting Reduce pressure and detach melt from part Source: http://www.cpcmachines.com

Macro Scale Simulation of the CPC Process Simulation requirements: • Capture the mold filling accurately – Furnace pressure drives mold filling • Phase change modelling – Thermal – Mushy Zone • Defect Prediction • Accurate initial conditions • Die cycling • Capture geometric details

Die Cycling Simplified mold Simplified Simplified Simplified mold mold mold Pure thermal Pure thermal Pure thermal Pure thermal Close die Close die filling filling filling filling simulation simulation simulation simulation Drying die Drying die Filling Filling parts parts spraying die spraying die Multiple Multiple Multiple Multiple casting casting casting cycles casting cycles cycles to cycles to to to parts parts reach „ reach reach reach „ „ „steady steady state steady steady state state state“ “ “ “ Solidification Solidification thermal conditions thermal thermal thermal conditions conditions conditions Removing Removing casting casting Open die Open die Cool down Cool down

Die Cycling – Results 1 2 3

STAR – Cast • Dedicated tool for Casting Simulations – Casting User Interface – Process driven setup – Single environment • CAD to post processing • Key Features: – Multiphase (VoF) Filling & Solidification – Criteria Functions for Defect Prediction – Material Database • CAD to Mesh – Native CAD import – Multi-Region Imprinting – Shell Generation Tool – Automated Polyhedral Meshing • Prismatic Boundary Layers

Strategic Partnership • Best of both worlds – Provide state of the art of casting simulation solution by combining the engineering experience of two companies which have a long-standing track record in providing CAE solutions and casting processes for over 25 years – Established casting solution STAR-Cast

Workflow Demonstration CPC

Casting of a Tire Rim Rim: A356, Casting Die: XCr38V1 @ Temperature: 680 degC Pressure Outlet 350 degC

Tire Rim – Simulation Workflow Geometry preparation Geometry preparation • 2 Hours • 2 Hours Meshing Meshing • 2 Hours (~1.4 Mio Cells) • 2 Hours (~1.4 Mio Cells) Physics Setup Physics Setup • 1 Hour • 1 Hour Simulation Run Simulation Run • 72 hours on 48 CPU’s • 72 hours on 48 CPU’s

Results

Thank you

Multiphase Simulation • Fully transient simulation • Immiscible Fluids: VOF model • Simultaneously solving for flow and energy: – Resolution of the filling front – Gas phase resolved via VoF model – Phase change – Conjugate heat transfer

Material Database A dedicated Material Database is available in STAR-Cast, pooling all relevant material information for the casting engineer

Defect Prediction • Aim is to provide additional information on the quality and structure of the casting – Shrinkage – Macro/ Micro Porosities – Primary/Secondary Dendrite Arm Spacing • Available Models – Criteria Functions – Macro Porosity Model centre line porosity Ref: Access, STAR- Ref: Access, STAR Ref: Access, STAR Ref: Access, STAR - - -Cast Cast Cast Cast