Simulation of a Hydraulic Cam Phaser Motion with 6-DOF morphing and Overset mesh Thomas Fischer, Daimler AG Berlin Plant Kai Fellmann, Daimler AG Berlin Plant Vienna, 03/17/2014
Organization 1. Introduction Design and Function of a Hydraulic Cam Phaser Tasks for the CFD Simulation with STAR-CCM+ 2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Java Macro for Controlling the Simulation 3. Selected Results 4. Summary 2
1. Introduction Design and Function of a Hydraulic Cam Phaser Tasks for the CFD Simulation with STAR-CCM+ 3
1. Introduction Design and Function of a Hydraulic Cam Phaser Inlet Outlet Cylinder head of a 4-cylinder gasoline engine with two cam phasers Cam phaser inlet 4
1. Introduction Design and Function of the Hydraulic Cam Phaser Electromagnetic valve actuator Sprocket Vane piston Camshaft Position valve with piston Lock pin 5
1. Introduction Design and Function of the Hydraulic Cam Phaser Electromagnetic valve actuator Sprocket Vane piston Camshaft Position valve with piston Lock pin 6
1. Introduction Tasks for the CFD Simulation with -CCM+ PhaseAngle Inlet R [[deg]] Calculated PhaseAngle Inlet R [deg] 10 0-10 -20-30 -40-50 10 0-10 -20-30 -40-50 Time [s] Time01 [sec] How does the design of the oil chambers affect the "adjustment speed" target variable? How can the performance of the system be improved by optimizing the oil chambers and the valve at the digital assembly stage? Calibration of the 1D system simulation at the digital assembly stage Less time and effort involved in testing 100 75 50 25 0 2 1.5 1 0.5 0-0.5-1 -1.5 TV NW2 [%] Spool Lift:ZV_P-AdvCh-1 [mm] Phasing Inlet right T=90 degc n=1000 rpm p=1,8 bar(rel.) Measurement 1D Simulation Temperature [ C] 120 110 100 90 80 70 60 50 40 30 Phasing speed [deg/s] 20 10 0-10 500 750 1000 1250 1500 1750 2000 2250 2500 2750 3000 Crank speed [rpm] 7
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Java Macro for Controlling the Simulation 8
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Cam Phaser Cylinder Head 9
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Cam Phaser Chamber Cam Shaft Bearing with Groove 10
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Pressure Outlet Stagnation Inlet 11
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Fixed Regions Motion Specification: Stationary Region CamShaft Motion Specification: Rotation 12
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Region Chamber Motion Specification: DFBI Morphing 13
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Region LockPin Motion Specification: DFBI Morphing Interface: Overset Mesh 14
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in STAR-CCM+ Volume Mesh Lock Pin Background / Overset Mesh 15
2. CFD Simulation of the Cam Phaser Design of the Simulation Model in Star-CCM+ Volume Mesh 16
2. CFD Simulation of the Cam Phaser Java Macro for Controlling the Simulation Start CurrAngle < MaxAngle? true false CurrentAngleRever se=currangle TimeStepForward =CurrentTimeStep End of Forward Movement Run Start Reverse Movement Current Time Step=? true Move Piston false Current Time Step=? true Move Piston false Current MinCell Quality <=? false Mesh Pipeline Mesh Pipeline true Mesh Pipeline 17
3. Selected Results 18
3. Selected Results Flow Speed Value at Selected Intersecting Planes 19
3. Selected Results Flow Speed Value at Selected Intersecting Planes 20
3. Selected Results Pressure Distribution During Adjustment 21
3. Selected Results Pressure Distribution During Adjustment 22
3. Selected Results Comparative Presentation of the Phasing Angle over Time for Different Design Variants 23
4. Summary 24
4. Summary Summary The hydraulic cam phaser can be simulated by means of different movements in STAR-CCM+. A Java macro is used for controlling the required valve movements and the remeshing of the morphed region. The modular simulation model can be easily adapted to new designs. The impact of the design of the oil chambers on the "adjustment speed" target variable can be calculated and optimized at the digital assembly stage. Calibrating the 1D system simulation at the digital assembly stage helps to generate reliable performance maps. The time and effort involved in testing is significantly reduced. 25
Thank you for your attention! Special thanks to the Nürnberg Support-Team! 26