Engine
Simple torque driver Engine component
The Engine component provides a first-approximation model for any type of internal combustion engine (spark ignition, diesel, etc.). The engine power characteristics are determined by a lookup table for power vs. engine speed data, or torque vs. engine speed data.
Equations
ϕm = ϕb −ϕsupport use support = true0otherwise
Where ϕb is the absolute rotation angle flangeb and the engine output torque is defined by:
τbt= −β · τout1t mode = torque vs speed τout2t mode = power vs speed
Where
0 ≤ β ≤ 1 is the throttle input
Also
τout1t= kT· {χinkω · ωmin· e−k0ωmin − ωmt 0 ≤ ωmt ≤ ωminχinkω · ωmt ωmin< ωmt < ωmaxχinkω · ωmax· e−k0ωmt − ωmax ωmin ≤ ωmt
and
τout2t= kpkω· {χinkω · ωminωmin· e−k0ωmin − ωmt 0 ≤ ωmt ≤ ωminχinkω · ωmtωmt ωmin< ωmt < ωmaxχinkω · ωmaxωmax· e−k0ωmt − ωmax ωmin ≤ ωmt
Where ωmin and ωmax are the lower and upper speed limits where the engine exerts torque, respectively.
Also k0 > 0 is a constant to adjust how quickly output torque goes to zero once the engine speed falls outside the set limits. kω, kp, and kT are the speed, power, and torque unit conversion factors, respectively.
χin is the interpolation function that uses user input data and depending on the choice for the mode parameter, the input data is either torque vs. speed data or power vs. speed data
Connections
Name
Condition
Description
ID
flangeb
-
Engine output shaft
flange_b
throttle β
Real input port for engine throttle, from 0 (idle) to 1 (maximum torque)
throttle
support
use support=true
Conditional Support Flange
loss
Parameters
Symbol
Default
Units
mode
torque vs. speed
Defines whether:
Torque vs. speed data is used to calculate engine torque [torque vs. speed] or
Power vs. speed data is used to calculate engine torque [power vs. speed]
enginedatamode
ωmin
100 π3
rads
Stall speed of the engine
minw
ωmax
200 π
Maximum speed of the engine
maxw
k0
0.1
srad
Factor controlling the rate at which engine torque goes to zero outside the operating range.
data source
GUI
Defines the source for the loss data:
entered via GUI [GUI]
by an attachment [attachment]
by an external file [file]
datasourcemode
use support
false
Enables/disables the support flange
useSupport
speed unit
RPM
Defines whether the speed data has the unit:
rad/s [rad/s]
RPM [RPM]
User defined [user-defined]
angularspeedunitmode
kω
speed unit = user defined
1
radsUuser
Speed conversion factor from the user-defined unit [Uuser] to rad/s
userspeedscale
torque unit
mode = torque vs. speed
N·m
Defines whether the torque data has the unit:
rad/s [N.m]
lb-ft [pound-feet]
torqueunitmode
kt
torque unit = user-defined
N·mUuser
Torque conversion factor from the user-defined unit [Uuser] to N.m
usertorquescale
power unit
mode = power vs. speed
kW
Watt [W]
Kilo Watt [kW]
horsepower [hp]
powerunitmode
kp
power unit = user-defined
WUuser
userpowerscale
data
data source = GUI
0, 260 1000, 260 1500, 325 2000, 360... 6500, 280 7000, 260 7500, 250
Defines engine curve:
if mode = [torque vs. speed]: the data is interpreted as speed-dependent maximum torque. (1st column speed, 2nd column torque)
if mode = [power vs. speed]:the data is interpreted as speed-dependent maximum power. (1st column speed, 2nd column power)
engineData
data source = attachment
−
if mode = [torque vs. speed]: the data is interpreted as speed-dependent maximum torque. (1st column speed, column number given by column parameter is torque)
if mode = [power vs. speed]: the data is interpreted as speed-dependent maximum power. (1st column speed, column number given by column parameter is power)
data source = file
fileName
column
data source = attachment or file
2
The column number where the engine data is stored
1st column is always the speed data
smoothness
Table points are linearly interpolated
Defines the smoothness of table interpolation
There are two options:
Table points are interpolated such that the first derivative is continuous
See Also
Driveline Library Overview
MapleSim Library Overview
1-D Mechanical Overview
Engines and Dynamometers
Download Help Document