CD-adapco STAR European Conference 2011 Automatic HVAC Workflow with STAR-CCM+ Georgios Apostolopoulos, Dr. Christian Merkle, Dr. Wolfram Kühnel Behr GmbH & Co. KG, Germany
Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Outline Behr Products CFD at Behr Simulation of HVACs Computation of temperature control curves Former approach: STAR-CD v3.26 + Harpoon Automatic HVAC workflow with STAR-CCM+ Conclusions Advantages and potential 2
Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Behr: Products Behr systems partner for total thermal management 3
Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Behr: CFD at Behr Typical examples 4
Simulation of HVACs Computation of temperature control curves Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Meaning of Temperature Control Curve (TCC) Typical air temperatures: 5 C after evaporator, 80 C after heater The position of the mixing flap defines the mass flux fractions of hot and cold air For computing the temperature control curve, only the mixing flap position is changed for the four outlets, the temperature should vary between 5 C and 80 C 5
Simulation of HVACs Former approach: STAR-CD v3.26 + Harpoon Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 manual preparation CAD automated part batch meshing fixed part(template): heat exchangers, ducts, solver settings variable part: housing, flaps, (+deflectors) automatic coupling to template model shortcut add baffles + restart new flap positions or geometric changes e.g. deflectors) initial model (coupled, pro-star panels) Simulation + Postprocessing ------------ Blower: pt1 [Pa] (PTBL) 251.588 ps1 [Pa] (PSBL) 148.607 dp Filter1 zu klein 0.000 0.000 dp Filter2 zu klein 0.000 0.000 ------------ Evap.: T [mm] (DEEV) 39.500 unif. index (UIEV) 0.890 pt1 [Pa] (PEV1) 220.581 pt2 [Pa] (PEV2) 159.756 dpt [Pa] 60.825 m [kg/s ] (MEV) 1.046e-01 m [ % ] (REV) 100.0 ps1 [Pa] (PEV3) 213.246 6
Simulation of HVACs Former approach: STAR-CD v3.26 + Harpoon Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Typical Postprocessing of HVAC Simulations Scalar scenes Bar pressure drop graphs Residual plots User defined quantities Advanced postprocessing in Fieldview Automatic report in MS-Word 7
Simulation of HVACs Automatic HVAC workflow with STAR-CCM+: Overview Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 One time work for a specific project Manual preparation Template sim file Import CAD in template sim file Organize/rename parts/surfaces Start HVAC Wizard Java automation plugin Repetitive work for every TCC point Rotate flaps panel Meshing Solving Automatic MS-Powerpoint report plugin Geometry Physics Meshing 8
Simulation of HVACs Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Automatic HVAC workflow with STAR-CCM+: HVAC Wizard plugin Extrusions representing real duct geometry Offset Parts Panel Selection of outlet part surface Selection of LCS Desired extrusion lengths Automatic extrusion and generation of new parts 9
Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Simulation of HVACs Automatic HVAC workflow with STAR-CCM+: HVAC Wizard plugin Rotate Flaps Panel Selection of flap Selection of percentage of rotation direction of rotation Automatic rotation of the respective part 10
Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Simulation of HVACs Automatic HVAC workflow with STAR-CCM+: MS-Powerpoint report plugin Automatic MS-Powerpoint report generation Scalar scenes Bar pressure drop graphs Residual plots User defined quantities 11
Automatic HVAC Workflow with STAR-CCM+ STAR European Conference 2011 Conclusions Advantages and potential The whole workflow is now done in one environment (from CAD import to MS-Powerpoint report generation) High usability of automatic HVAC workflow tool, but difficult to maintain over different STAR-CCM+ releases Automatic java macro update tool highly appreciated Total process time Temperature Control Curve: comparable Geometry optimization: slower due to meshing time Meshing time is considerably longer with STAR-CCM+ compared to Harpoon High memory requirement of STAR-CCM+ in comparison with STAR-CD workflow Modifications of the geometry require the remeshing of the whole HVAC geometry Parallel meshing, local remeshing, overlapping grids Different porosity model compared to STAR-CD (Darcy s-law announced for v6.04) 12