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nknighta/as408.mr

Created June 14, 2025 20:10
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engine simulator script
Raw
as408.mr
import "engine_sim.mr"
units units()
constants constants()
impulse_response_library ir_lib()
label cycle(2 * 360 * units.deg)
private node wires {
output wire1: ignition_wire();
output wire2: ignition_wire();
output wire3: ignition_wire();
output wire4: ignition_wire();
output wire5: ignition_wire();
output wire6: ignition_wire();
output wire7: ignition_wire();
output wire8: ignition_wire();
}
private node v10_72_head {
input intake_camshaft;
input exhaust_camshaft;
input chamber_volume: 1.5 * 25 * units.cc;
input intake_runner_volume: 149.6 * units.cc;
input intake_runner_cross_section_area: 1.75 * units.inch * 1.75 * units.inch;
input exhaust_runner_volume: 50.0 * units.cc;
input exhaust_runner_cross_section_area: 2.5 * units.inch * 2.5 * units.inch;
input flow_attenuation: 1.0;
input lift_scale: 1.0;
input flip_display: false;
alias output __out: head;
function intake_flow(50 * units.thou)
intake_flow
.add_flow_sample(0 * lift_scale, 0 * flow_attenuation)
.add_flow_sample(50 * lift_scale, 58 * flow_attenuation)
.add_flow_sample(100 * lift_scale, 103 * flow_attenuation)
.add_flow_sample(150 * lift_scale, 156 * flow_attenuation)
.add_flow_sample(200 * lift_scale, 214 * flow_attenuation)
.add_flow_sample(250 * lift_scale, 249 * flow_attenuation)
.add_flow_sample(300 * lift_scale, 268 * flow_attenuation)
.add_flow_sample(350 * lift_scale, 280 * flow_attenuation)
.add_flow_sample(400 * lift_scale, 280 * flow_attenuation)
.add_flow_sample(450 * lift_scale, 281 * flow_attenuation)
function exhaust_flow(50 * units.thou)
exhaust_flow
.add_flow_sample(0 * lift_scale, 0 * flow_attenuation)
.add_flow_sample(50 * lift_scale, 37 * flow_attenuation)
.add_flow_sample(100 * lift_scale, 72 * flow_attenuation)
.add_flow_sample(150 * lift_scale, 113 * flow_attenuation)
.add_flow_sample(200 * lift_scale, 160 * flow_attenuation)
.add_flow_sample(250 * lift_scale, 196 * flow_attenuation)
.add_flow_sample(300 * lift_scale, 222 * flow_attenuation)
.add_flow_sample(350 * lift_scale, 235 * flow_attenuation)
.add_flow_sample(400 * lift_scale, 245 * flow_attenuation)
.add_flow_sample(450 * lift_scale, 246 * flow_attenuation)
generic_cylinder_head head(
chamber_volume: chamber_volume,
intake_runner_volume: intake_runner_volume,
intake_runner_cross_section_area: intake_runner_cross_section_area,
exhaust_runner_volume: exhaust_runner_volume,
exhaust_runner_cross_section_area: exhaust_runner_cross_section_area,
intake_port_flow: intake_flow,
exhaust_port_flow: exhaust_flow,
valvetrain: standard_valvetrain(
intake_camshaft: intake_camshaft,
exhaust_camshaft: exhaust_camshaft
),
flip_display: flip_display
)
}
private node v10_72_camshaft {
input lobe_profile;
input intake_lobe_profile: lobe_profile;
input exhaust_lobe_profile: lobe_profile;
input lobe_separation: 114 * units.deg;
input intake_lobe_center: lobe_separation;
input exhaust_lobe_center: lobe_separation;
input advance: 0 * units.deg;
input base_radius: 0.5 * units.inch;
output intake_cam_0: _intake_cam_0;
output exhaust_cam_0: _exhaust_cam_0;
output intake_cam_1: _intake_cam_1;
output exhaust_cam_1: _exhaust_cam_1;
camshaft_parameters params (
advance: advance,
base_radius: base_radius
)
camshaft _intake_cam_0(params, lobe_profile: intake_lobe_profile)
camshaft _exhaust_cam_0(params, lobe_profile: exhaust_lobe_profile)
camshaft _intake_cam_1(params, lobe_profile: intake_lobe_profile)
camshaft _exhaust_cam_1(params, lobe_profile: exhaust_lobe_profile)
label rot(72 * units.deg)
label rot360(360 * units.deg)
// 1 2 3 4 7 8 9 10 5 6
_exhaust_cam_0
.add_lobe(rot360 - exhaust_lobe_center + 0 * rot) // 1
.add_lobe(rot360 - exhaust_lobe_center + 2 * rot) // 3
.add_lobe(rot360 - exhaust_lobe_center + 8 * rot) // 5
.add_lobe(rot360 - exhaust_lobe_center + 4 * rot) // 7
.add_lobe(rot360 - exhaust_lobe_center + 6 * rot) // 9
_intake_cam_0
.add_lobe(rot360 + intake_lobe_center + 0 * rot) // 1
.add_lobe(rot360 + intake_lobe_center + 2 * rot) // 3
.add_lobe(rot360 + intake_lobe_center + 8 * rot) // 5
.add_lobe(rot360 + intake_lobe_center + 4 * rot) // 7
.add_lobe(rot360 + intake_lobe_center + 6 * rot) // 9
_exhaust_cam_1
.add_lobe(rot360 - exhaust_lobe_center + 1 * rot) // 2
.add_lobe(rot360 - exhaust_lobe_center + 3 * rot) // 4
.add_lobe(rot360 - exhaust_lobe_center + 9 * rot) // 6
.add_lobe(rot360 - exhaust_lobe_center + 5 * rot) // 8
.add_lobe(rot360 - exhaust_lobe_center + 7 * rot) // 10
_intake_cam_1
.add_lobe(rot360 + intake_lobe_center + 1 * rot) // 2
.add_lobe(rot360 + intake_lobe_center + 3 * rot) // 4
.add_lobe(rot360 + intake_lobe_center + 9 * rot) // 6
.add_lobe(rot360 + intake_lobe_center + 5 * rot) // 8
.add_lobe(rot360 + intake_lobe_center + 7 * rot) // 10
}
public node lr_gue_v10 {
alias output __out: engine;
engine engine(
name: "AS408RS",
starter_torque: 150 * units.lb_ft,
starter_speed: 700 * units.rpm,
redline: 9400 * units.rpm,
throttle_gamma: 2.0,
fuel: fuel(
max_turbulence_effect: 10.0,
max_dilution_effect: 20.0,
burning_efficiency_randomness: 0.25,
max_burning_efficiency: 1.0
),
hf_gain: 0.01,
noise: 1.0,
jitter: 0.1,
simulation_frequency: 6500
)
wires wires()
label stroke(68 * units.mm)
label bore(100 * units.mm)
label rod_length(125 * units.mm)
label rod_mass(60 * units.g)
label compression_height(1.0 * units.inch)
label crank_mass(40 * units.lb)
label flywheel_mass(30 * units.lb)
label flywheel_radius(6.5 * units.inch)
label crank_moment(
disk_moment_of_inertia(mass: crank_mass, radius: stroke)
)
label flywheel_moment(
disk_moment_of_inertia(mass: flywheel_mass, radius: flywheel_radius)
)
label other_moment( // Moment from cams, pulleys, etc [estimated]
disk_moment_of_inertia(mass: 1 * units.kg, radius: 1.0 * units.cm)
)
label v_angle(80 * units.deg)
crankshaft c0(
throw: stroke / 2,
flywheel_mass: flywheel_mass,
mass: crank_mass,
friction_torque: 0.0 * units.lb_ft,
moment_of_inertia:
crank_moment + flywheel_moment + other_moment,
position_x: 0.0,
position_y: 0.0,
tdc: 90 * units.deg + (v_angle / 2.0)
)
// 72 degrees
rod_journal rj0(angle: 0 * v_angle)
rod_journal rj1(angle: 2 * v_angle)
rod_journal rj2(angle: 3 * v_angle)
rod_journal rj3(angle: 4 * v_angle)
rod_journal rj4(angle: 1 * v_angle)
c0
.add_rod_journal(rj0)
.add_rod_journal(rj1)
.add_rod_journal(rj2)
.add_rod_journal(rj3)
.add_rod_journal(rj4)
piston_parameters piston_params(
mass: (100) * units.g, // 414 - piston mass, 152 - pin weight
compression_height: compression_height,
wrist_pin_position: 0.0,
displacement: 0.0
)
connecting_rod_parameters cr_params(
mass: rod_mass,
moment_of_inertia: rod_moment_of_inertia(
mass: rod_mass,
length: rod_length
),
center_of_mass: 0.0,
length: rod_length
)
intake intake(
plenum_volume: 1.325 * units.L,
plenum_cross_section_area: 20.0 * units.cm2,
intake_flow_rate: k_carb(1000.0),
runner_flow_rate: k_carb(200.0),
runner_length: 4.0 * units.inch,
idle_flow_rate: k_carb(0.0),
idle_throttle_plate_position: 0.997,
velocity_decay: 0.5
)
exhaust_system_parameters es_params(
outlet_flow_rate: k_carb(2000.0),
primary_tube_length: 50.0 * units.inch,
primary_flow_rate: k_carb(1000.0),
velocity_decay: 1.0
)
exhaust_system exhaust0(
es_params,
audio_volume: 2.0,
length: 100 * units.inch,
impulse_response: ir_lib.mild_exhaust_0_reverb
)
exhaust_system exhaust1(
es_params,
audio_volume: 2.0,
length: 100.5 * units.inch,
impulse_response: ir_lib.mild_exhaust_0_reverb
)
cylinder_bank_parameters bank_params(
bore: bore,
deck_height: stroke / 2 + rod_length + compression_height
)
cylinder_bank b0(bank_params, angle: v_angle / 2.0)
cylinder_bank b1(bank_params, angle: -v_angle / 2.0)
b0
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj0,
intake: intake,
exhaust_system: exhaust1,
ignition_wire: wires.wire1,
sound_attenuation: 0.8,
primary_length: 5 * units.cm
)
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj1,
intake: intake,
exhaust_system: exhaust1,
ignition_wire: wires.wire3,
sound_attenuation: 1.0,
primary_length: 4 * units.cm
)
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj2,
intake: intake,
exhaust_system: exhaust1,
ignition_wire: wires.wire5,
sound_attenuation: 1.1,
primary_length: 3 * units.cm
)
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj3,
intake: intake,
exhaust_system: exhaust1,
ignition_wire: wires.wire7,
sound_attenuation: 0.9,
primary_length: 2 * units.cm
)
.set_cylinder_head(
v10_72_head(
intake_camshaft: camshaft.intake_cam_0,
exhaust_camshaft: camshaft.exhaust_cam_0,
flip_display: true,
flow_attenuation: 1.5)
)
b1
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj0,
intake: intake,
exhaust_system: exhaust0,
ignition_wire: wires.wire2,
sound_attenuation: 0.7,
primary_length: 5 * units.cm
)
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj1,
intake: intake,
exhaust_system: exhaust0,
ignition_wire: wires.wire4,
sound_attenuation: 0.8,
primary_length: 4 * units.cm
)
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj2,
intake: intake,
exhaust_system: exhaust0,
ignition_wire: wires.wire6,
primary_length: 3 * units.cm
)
.add_cylinder(
piston: piston(piston_params, blowby: k_28inH2O(0.0)),
connecting_rod: connecting_rod(cr_params),
rod_journal: rj3,
intake: intake,
exhaust_system: exhaust0,
ignition_wire: wires.wire8,
sound_attenuation: 1.1,
primary_length: 2 * units.cm
)
.set_cylinder_head(
v10_72_head(
intake_camshaft: camshaft.intake_cam_1,
exhaust_camshaft: camshaft.exhaust_cam_1,
flow_attenuation: 1.5)
)
engine
.add_cylinder_bank(b0)
.add_cylinder_bank(b1)
engine.add_crankshaft(c0)
harmonic_cam_lobe intake_lobe(
duration_at_50_thou: 230 * units.deg,
gamma: 1.1,
lift: 15.95 * units.mm,
steps: 100
)
harmonic_cam_lobe exhaust_lobe(
duration_at_50_thou: 230 * units.deg,
gamma: 1.1,
lift: 15.95 * units.mm,
steps: 100
)
v10_72_camshaft camshaft(
lobe_profile: "N/A",
intake_lobe_profile: intake_lobe,
exhaust_lobe_profile: exhaust_lobe,
intake_lobe_center: 110 * units.deg,
exhaust_lobe_center: 112 * units.deg,
base_radius: 0.9 * units.inch
)
function timing_curve(4000 * units.rpm)
timing_curve
.add_sample(0000 * units.rpm, 12 * units.deg)
.add_sample(4000 * units.rpm, 40 * units.deg)
.add_sample(8000 * units.rpm, 40 * units.deg)
.add_sample(12000 * units.rpm, 40 * units.deg)
.add_sample(14000 * units.rpm, 40 * units.deg)
.add_sample(18000 * units.rpm, 40 * units.deg)
ignition_module ignition_module(
timing_curve: timing_curve,
rev_limit: 9700 * units.rpm,
limiter_duration: 0.1)
ignition_module
.connect_wire(wires.wire1, 0 * 72 * units.deg)
.connect_wire(wires.wire2, 1 * 72 * units.deg)
.connect_wire(wires.wire3, 2 * 72 * units.deg)
.connect_wire(wires.wire4, 3 * 72 * units.deg)
.connect_wire(wires.wire7, 4 * 72 * units.deg)
.connect_wire(wires.wire8, 5 * 72 * units.deg)
.connect_wire(wires.wire5, 8 * 72 * units.deg)
.connect_wire(wires.wire6, 9 * 72 * units.deg)
engine.add_ignition_module(ignition_module)
}
private node s44 {
alias output __out:
vehicle(
mass: 1264 * units.kg,
drag_coefficient: 0.3,
cross_sectional_area: (72 * units.inch) * (50 * units.inch),
diff_ratio: 3.42,
tire_radius: 11 * units.inch,
rolling_resistance: 200 * units.N
);
}
private node lfa_transmission {
alias output __out:
transmission(
max_clutch_torque: 1100 * units.lb_ft
)
.add_gear(3.23)
.add_gear(2.19)
.add_gear(1.61)
.add_gear(1.23)
.add_gear(0.97)
.add_gear(0.83)
.add_gear(0.70);
}
public node main {
run(
engine: lr_gue_v10(),
vehicle: s44(),
transmission: lfa_transmission()
)
}
main()
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