Optimized front-end cooling module with COOL3D French GT Conference 2017 Wednesday, May 17 LECLERCQ Cyril CHARDEL Fabrice
AGENDA o Context & motivation o GT-SUITE evaluation plan o COOL3D approach for underhood simulation o Synthesis of correlation campaign o Conclusion and perspectives 2
CONTEXT & MOTIVATION o Multiple challenges for cooling module design : Sophisticated vehicle thermal architectures : Multiple coolant loops An increasing number of front-end exchangers A worldwide market and a competitive environment : Many cooling module derivatives adapted for country and climate specificities Need for a faster design process for early design stages Traditional tools and inadapted design methodologies : CFD simulation toolset inappropriate for reactive analysis or thermal architecture building Costs of experimental testing (prototype, wind tunnel tests) o Need for a quick and predictive tool to evaluate cooling performance with a good accuracy to build efficient thermal architecture at early stages of vehicle design o 2016 : PSA group aimed to evaluate GT-SUITE and COOL3D to enhance its simulation toolset 3
GT-SUITE EVALUATION PLAN o Several vehicle platforms and different cooling module architectures Low and medium segment Parallel and serial module configuration o Test campaign with a large number of derivatives Size and position of air intakes Front-end leakages Aeraulics permeability of heat exchangers o Comparison of COOL3D simulation vs full CFD vs Wind tunnel results 4
COOL3D APPROACH FOR UNDERHOOD SIMULATION (1/4) o Presented vehicle configuration = 308 model o Cooling architecture = serial-type module (condenser + radiator + fan) with a separated air path for charge air cooler (outlet in the wheel housing) 5
COOL3D APPROACH FOR UNDERHOOD SIMULATION (2/4) o Overall gross geometry for powertrain modelling o Boundary condition for air intake & underhood outlet = total pressure from CFD results Radiator Fan Charge air cooler Front Fascia Condenser Fan Shroud 6
COOL3D APPROACH FOR UNDERHOOD SIMULATION (3/4) o Example of thermal loops design : coupling of refrigerant loop and underhood model Underhood Radiator CAC Condensor FAN Refrigerant loop 7
X-position COOL3D APPROACH FOR UNDERHOOD SIMULATION (4/4) o Example of optimization for cooling module design o Cooling architecture = parallel-type module (side-by-side exchangers) o Optimisation between cooling module X-position and fan Y-position X-position Interferences with bumper beam and powertrain (downstream blocage) Y-position Interferences with front-end-oriented exhaust line (depending on module X-position) ref + XXX mm Y-position ref + YYY mm configurations n 1 to 15 Best configuration = CF13 8
Heat losses (kw) SYNTHESIS OF CORRELATION CAMPAIGN (1/2) o Comparison of COOL3D simulation vs full CFD vs Wind tunnel results o Conclusion is positive for predictive capabilities of GT-SUITE Radiator air temperature map (downstream) Radiator heat losses COOL3D 90 80 70 60 50 40 30 20 10 FULL CFD 0 10 25 50 90 140 190 Vehicle speed (km/h) GT COOL3D Full CFD Wind Tunnel results 9
SYNTHESIS OF CORRELATION CAMPAIGN (2/2) o Compared to full CFD, GT-SUITE provides good accuracy regarding to modeling and calculation speed CFD simulation COOL3D simulation Needs for model construction Detailed geometry Heat exchangers maps Overall geometry Heat exchangers maps Processing duration Weeks ( 3 to 6) Days ( 3) Prediction accuracy +/- 3% +/-10% 10
CONCLUSION AND PERSPECTIVES o The 2016 evaluation campaign of GT-SUITE for cooling module design is positive o GT-SUITE are quick and sufficient predictive tools for early stages of cooling module design process o Next steps : o More testing (early beginning of tools practice) o Skill developpment of PSA technical team 2017 o Optimise models to study both steady state and transient problems 11