Decomposition Analysis of an Automotive Powertrain Design ...

APPENDIX A: Powertrain Model Summary
Table A.1: Summary of geometric, behavior, and state
variables.
Index Variable Partition Description
0 η cat 1 Catalyst efficency
1 V 2 Vehicle velocity
2 dV/dt 2 Vehicle acceleration
3 p i y Intake manifold pressure
4 F nd 2 Normal force at driving wheels
5 F nnd 2 Normal force at non-driving wheels
6 N e y Engine speed
7 dN e /dt 2 Engine acceleration
8 N t 2 Torque converter turbine speed
9 dN t /dt 2 Torque converter turbine acceleration
10 N ds 2 Drive shaft speed
11 dN ds /dt 2 Drive shaft acceleration
12 N d 2 Driving axle speed
13 dN d /dt 2 Driving axle acceleration
14 S 2 Slip ratio
15 R s 2 Speed ratio across torque converter
16 T e y Engine torque
17 T i 2 Torque converter impeller torque
18 T gb 2 Torque entering gearbox
19 T fd 2 Torque entering final drive
20 T ch 2 Churning losses in gear box
21 T d 2 Torque at driving axle
22 F d 2 Force at drving wheel/road interface
23 α 2 Grade angle
24 α s 2 Starting grade angle
25 V c 2 Cruising speed at 7% grade.
26 A 2 Vehicle frontal area
27 C d 2 Vehicle body drag coefficient
28 F aero 2 Aerodynamic resistance force
29 F roll 2 Rolling resistance force
30 C roll 2 Coefficient of rolling resistance
31 F grade 2 Grade resistance force
32 H cg 2 Height of center of gravity
33 H a 2 Height of aerodynamic effort
34 M 2 Mass of vehicle
35 L d 2 Distance from center of gravity to driving axle