Forward 1D Vehicle Dynamics Simulation ocused on Fuel Consumption Concerns with the Inclusion of the Complete Driveline and Accessory Load Influence MWM-International Motores Ltda

Format:

Conference/Event

Author/Creator:

Almeida, Almeida, author.

Contributor:

Capana, Giulliano Humberto

de Moraes, Herickson Faria

Sokolowski, Damian

Conference Name:

21st SAE Brasil International Congress and Exhibition (2012-10-02 : Sao Paulo, Brazil)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2012

Summary:

A great part of the projects in the powertrain area is focusedon the development of more efficient thermal applications. In theend, efficiency is pursued, since the aim is to achieve asustainable design with low fuel consumption. Thus, vehicles whichpresent lower fuel consumption are demanded by customers.Additionally the emission standards have been reducing the limitsof CO₂ emissions to very low levels, which drive engineers todevelop vehicles with lower fuel consumption. In summary, theproduct should now please a more demanding worldwide customerprofile as the global economy grows. Vehicle design processesshould consider fuel consumption sensitivity taking into accountthe combined engine and drive train systems at early stages.Frequently the actual fuel consumption can only be confirmed whenthe first prototype is assembled in order to validate the adoptedsolutions. On the other hand, project timing is another dominantconstraint, even when using planning of experiments (DoE) not allproposed designs can be tested. In this sense, the use of numericalsimulation resources has been more and more utilized to reduceproject timing. A vehicle simulation of a 4-cylinder dieselinternal combustion engine (ICE) coupled with the driveline of thevehicle, including its accessories, was developed utilizing thenumerical 1D model, built in GT-Suite, a Gamma Technologies, Incorporated,code. A multi-body dynamics method was used with explicitconsideration of accessory loads and the engine, which wasrepresented by its maps evaluated at the dyno, namely BMEP, FMEPand BSFC. The model calibration was done using some route acquireddata in order to reproduce the measured fuel consumption under somespecific vehicle cruise conditions and 3 accelerations rampsituations. The pedal position was assigned by a PID controllerrepresenting a virtual driver's behavior. The gear shiftschedule was calculated inversely by inspection pursuing areasonable correlation of the simulated and measured fuel rates.The aerodynamics features and the rolling resistance coefficientwere adopted based on information provided by the customer and thedynamic tire radius were inversely calculated using GPS vehiclespeed data, engine speed and drive line ratios.This paper presents a study of the impact of accessory loads ina physically-representative way. Their loads have been consideredvia their power consumption curve. Each one has been studied andmodeled in order to get a representative power curve shape over therelevant speed range for the engine. Then, they were all includedin the 1D dynamic model. The final numerical model presented 6% ofmax difference in total fuel consumption in comparison tomeasurements for all 6 cruise situations without the need of anycalibration adjustment, which is a usual practice worldwide. Theacceleration behavior of the model presented a max difference of 7%(with a minimum of 2%) in comparison to measurements in terms ofacceleration times and vehicle displacements. The aforementionedresults were considered excellent from the perspective of theadopted 1D approach. The model has already served as a good basisto evaluate the contribution of each accessory load on the totalfuel consumption in order to provide technical basis for a systemoptimization, which might lead to an eventual modification of theaccessory design. Last but not least, it may help with theaccessory supplier competition

Notes:

Vendor supplied data

Publisher Number:

2012-36-0247

Access Restriction:

Restricted for use by site license