Vehicle simulation with cylinder deactivation

Transcription

1 Vehicle simulation with cylinder deactivation Potential analysis of cylinder deactivation using a detailed Cyrille Frottier, Lars Böttcher, GT-SUITE Users Conference, October 2011

2 Vehicle simulation with cylinder deactivation Table of content kallejipp / photocase.com IAV 10/2011 CF DA-E4 2

3 GT-SUITE build-up Combination of GT-POWER and GT-SUITE for an advanced with very high variation possibilities The aim is to use the advantage of a detailed engine and advantages GT-POWER + consider engine specific parameter e.g. EGR, volumetric eff., turbo charging, geometric characteristics, different influences of temperature and pressure GT-SUITE + consider specific parameter e.g. transmission, clutch, driver behaviour, different influences of driveline picture: IAV 10/2011 CF DA-E4 3

4 GT-SUITE build-up GT-POWER GT-SUITE combination desired main input is heat release high variation possibilities of specific body and engine parameter interaction between body and engine actuation of pedals with a realistic driver implementation of a ECU to control the different engine features pictures: IAV 10/2011 CF DA-E4 4

5 Cylinder deactivation Cylinder deactivation Cylinder deactivation has been developed by several OEM s for high cylinder number engines (e.g. V6 or V8 engines). By using the cylinder deactivation on a four cylinder gasoline engine, a serious pumping losses decrease is expected resulting in a rise of the indicated efficiency. Fuel consumption benefit BMEP [bar] Engine speed [rpm] IAV 10/2011 CF DA-E4 5

6 Steady-state: Indicated efficiency map w/ 4 or 2 cylinders Indicated efficiency [-] of cylinder 1 Focus on one cylinder A IMEP [bar] B A B Engine speed [rpm] IAV 10/2011 CF DA-E4 6

7 Steady-state: Indicated efficiency benefit i i, HP i, LP W i, HP Wi, LP Q i, i HP W i, HP Q i W i, LP 1 W i, LP i, HP A Operating point n Torque M_eff [1/min] [Nm] i IMEP cyl.1 = 2 bar i, HP i, LP B IMEP cyl.1 = 4 bar i i, HP i, LP Pcyl.1 [bar] Pcyl.1 [bar] Vcyl/Vmax [-] Vcyl/Vmax [-] With 2 cylinders, a higher IMEP is needed, produced with a higher combustion work (& higher thermal efficiency) which reduces seriously the impact of the pumping losses. IAV 10/2011 CF DA-E4 7

8 Steady-state: Effective efficiency map w/ 4 cylinders Effective efficiency [-] Focus during a A A Break torque [Nm] Engine speed [rpm] IAV 10/2011 CF DA-E4 8

9 Steady-state: Effective efficiency map w/ 4 or 2 cylinders Effective efficiency [-] Focus during a A A Break torque [Nm] B B Valve closed Engine speed [rpm] A constant mechanical efficiency was held for a first estimation. IAV 10/2011 CF DA-E4 9

10 A detailed enables to investigate strategies during driving s like: design improvements regarding the catalyst heating variable valve train variations cylinder deactivation strategy 1.6l 4cyl. engine car and driver pictures: ECU (includes idle controller) IAV 10/2011 CF DA-E4 10

11 Subassemblies Car and driver subassembly Vehicle controllers used depending on phase. IAV 10/2011 CF DA-E4 11

12 Subassemblies Car and driver subassembly Vehicle controllers used depending on phase. IAV 10/2011 CF DA-E4 12

13 Subassemblies Car and driver subassembly Vehicle controllers used depending on phase. IAV 10/2011 CF DA-E4 13

14 Subassemblies Car and driver subassembly Engine subassembly Some features: Variable FMEP depending on the running conditions (cold start) Catalyst heating strategy Deceleration fuel cut off Vehicle controllers used depending on phase. Cylinder deactivation through Eventmanager template. IAV 10/2011 CF DA-E4 14

15 Subassemblies Car and driver subassembly Engine subassembly Some features: Variable FMEP depending on the running conditions (cold start) Catalyst heating strategy Deceleration fuel cut off Vehicle controllers used depending on phase. Cylinder deactivation through Eventmanager template. IAV 10/2011 CF DA-E4 15

16 Driving phase indicator speed target time delay difference ST TD ME speed time Information about target driving status Acceleration, Deceleration, Plateau Vehicle parameter Depending on driving status and tractive resistance, different proportional and integral gains will be selected dedicated to the controllers Result in an intelligent control with a high flexibility for every s IAV 10/2011 CF DA-E4 16

17 Target speed vs. simulated speed Vehicle speed [km/h] Vehicle speed [km/h] adapted catalyst heating inner city part part 1 Simulation Time [sec] Measurements Vehicle speed [km/h] Vehicle speed [km/h] adapted extra urban part Simulation Time [sec] Measurements Time [sec] Time [sec] IAV 10/2011 CF DA-E4 17

18 Cylinder deactivation strategy 2 cylinders NEDC inner city part extra urban part 4 cylinders Vehicle speed [km/h] part 1 part 2 part 3 part 4 2 cylinders + boosting or 4 cylinders Time [sec] IAV 10/2011 CF DA-E4 18

19 EUDC driving strategy : 7.61L/100km : 7.14L/100km : 7.05L/100km Fuel Mass [kg] NEDC -6.2% -1.3% 4 cyl. 4 cyl. 4 cyl. 4 cyl. 2 cyl. 4 cyl. 4 cyl. 2 cyl. 2 cyl. with boosting impact of 2 cylinder use Time [sec] Vehicle speed [km/h] Utilizing 2 cylinders instead of 4 cylinders during ECE provides a large benefit because of the pumping losses difference. Utilizing the wastegate with 2 cylinders instead of utilizing the 4 cylinders provides only a slight difference because the pumping losses during EUDC are quite low. IAV 10/2011 CF DA-E4 19

20 Assessment of simulation process stand alone (step 1): GT-POWER engine specific investigations GT-SUITE specific investigations serial module procedure (step 2 and/or 3): new implementation control effort GT-SUITE kinematic mode GT-POWER speed specification transient min. simulation time: 1min + 4h inaccuracy: <10% (NEDC, consumption) GT-SUITE kinematic mode GT-POWER load specification transient min. simulation time: 1min + 6h inaccuracy: <5% (NEDC, consumption) parallel module procedure (step 4): GT-SUITE GT-POWER min. simulation time: 9-10h inaccuracy: <1% (NEDC, consumption) IAV 10/2011 CF DA-E4 20

21 High flexible dedicated to engine strategies investigations during driving s For instance, the cylinder deactivation technology can be accurately estimated depending on the strategies chosen Calculation time of such a is about 9-10 hours for a NEDC (over night) Next steps Implementation of predictive heat transfer (instead of maps) Implementation of predictive friction (instead of maps) The new technology FRM (keeping the cylinder templates) should be tried out as the first tests from Gamma Technologies are very promising (NEDC < 1 hour) IAV 10/2011 CF DA-E4 21

22 Thank You Cyrille Frottier IAV GmbH Telefon