Steam Engine Design/Free Piston Steam Hydraulic/SpiceCode

LTSpice IV code for Free Piston Steam Engine simulation

FreePiston.asc 20-Nov-2011

Version 4
SHEET 1 2028 680
WIRE 1072 -480 1008 -480
WIRE 1120 -480 1072 -480
WIRE 1008 -448 1008 -480
WIRE 1520 -400 1424 -400
WIRE 1728 -400 1520 -400
WIRE 1744 -400 1728 -400
WIRE 1760 -352 1744 -352
WIRE 1008 -336 1008 -368
WIRE 1424 -320 1424 -400
WIRE 1520 -320 1520 -400
WIRE 1744 -320 1744 -352
WIRE 448 -288 336 -288
WIRE 1088 -288 1008 -288
WIRE 1008 -272 1008 -288
WIRE 336 -256 336 -288
WIRE 1520 -208 1520 -240
WIRE 1744 -208 1744 -240
WIRE 1008 -176 1008 -192
WIRE 336 -144 336 -176
WIRE 992 -96 944 -96
WIRE 1008 -96 992 -96
WIRE 448 -64 448 -288
WIRE 1008 -64 1008 -96
WIRE 64 -48 -32 -48
WIRE 288 -48 192 -48
WIRE 400 -48 288 -48
WIRE 1152 -48 1056 -48
WIRE 1168 -48 1152 -48
WIRE 1424 -48 1424 -256
WIRE 1424 -48 1168 -48
WIRE 1424 -32 1424 -48
WIRE 1744 -32 1424 -32
WIRE 400 0 384 0
WIRE 1088 0 1056 0
WIRE 384 16 384 0
WIRE -32 32 -32 -48
WIRE 1152 32 1152 -48
WIRE 1744 32 1744 -32
WIRE 1696 48 1584 48
WIRE 128 64 128 32
WIRE 1008 64 1008 16
WIRE 448 80 448 16
WIRE 832 80 448 80
WIRE 896 80 832 80
WIRE 960 80 896 80
WIRE 1424 112 1424 -32
WIRE 1696 128 1696 96
WIRE -32 144 -32 112
WIRE 1152 160 1152 112
WIRE 1584 160 1584 48
WIRE 1744 160 1744 112
WIRE 896 176 896 80
WIRE 960 176 960 128
WIRE 1088 176 1088 0
WIRE 1088 176 960 176
WIRE 1088 192 1088 176
WIRE 448 272 448 80
WIRE 1424 272 1424 176
WIRE 224 288 -112 288
WIRE 400 288 224 288
WIRE 1088 288 1088 272
WIRE 1008 304 1008 144
WIRE 1584 304 1584 240
WIRE 400 336 384 336
WIRE 896 336 896 240
WIRE 384 352 384 336
WIRE -112 368 -112 288
WIRE 448 400 448 352
WIRE 1008 448 1008 384
WIRE -112 480 -112 448
WIRE 448 512 448 480
WIRE 1008 560 1008 528
FLAG 448 512 0
FLAG 336 -144 0
FLAG 832 80 CYL_PR
FLAG 1424 272 0
FLAG 1744 160 0
FLAG 1520 -208 0
FLAG 1168 -48 HYDR_PR
FLAG 1008 560 0
FLAG 992 -96 NET_FORCE
FLAG 896 336 0
FLAG 384 16 0
FLAG 384 352 0
FLAG 1696 128 0
FLAG 1152 160 0
FLAG 1008 -336 0
FLAG 1072 -480 CYL_POSN
FLAG 224 288 exh_open
FLAG 288 -48 inlet_open
FLAG 1584 304 0
FLAG -32 144 0
FLAG 128 64 0
FLAG -112 480 0
FLAG 1008 -176 0
FLAG 1088 -288 CYL_VELOC
FLAG 1728 -400 H_OUT
FLAG 1088 288 0
FLAG 1744 -208 0
FLAG 1744 -352 AVG_FLOW
SYMBOL voltage 336 -272 R0
WINDOW 3 -128 105 Left 2
SYMATTR Value {Pb + Patm}
SYMATTR InstName V1
SYMBOL sw 448 368 M180
WINDOW 3 9 106 Left 2
SYMATTR InstName S1
SYMATTR Value SteamExh
SYMBOL sw 448 32 M180
SYMATTR InstName S2
SYMATTR Value SteamIn
SYMBOL diode 1440 -256 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMATTR Value OutCheck
SYMBOL diode 1440 176 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D2
SYMATTR Value SuctionCheck
SYMBOL sw 1744 128 M180
SYMATTR InstName S3
SYMATTR Value SuctionValve
SYMBOL voltage 1520 -336 R0
WINDOW 123 0 0 Left 2
WINDOW 39 24 44 Left 2
SYMATTR InstName V2
SYMATTR Value {Pacc+Patm}
SYMBOL e 1008 48 R0
WINDOW 3 12 103 Left 2
SYMATTR InstName E1
SYMATTR Value {Asp}
SYMBOL e 1008 -80 M0
SYMATTR InstName E2
SYMATTR Value {-Ahp}
SYMBOL cap 880 176 R0
WINDOW 3 -413 4 Left 2
SYMATTR InstName C1
SYMATTR Value Q={Rbp*pow(Ahp*V(cyl_posn),gam)*x}
SYMATTR Value2 ic=0
SYMBOL bi 1152 32 R0
WINDOW 0 10 -22 Left 2
WINDOW 3 11 100 Left 2
SYMATTR InstName B2
SYMATTR Value I=-Ahp*V(cyl_veloc)
SYMBOL voltage 448 384 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V6
SYMATTR Value {Pc+Patm}
SYMBOL bv 1008 -464 R0
SYMATTR InstName B1
SYMATTR Value V={ idt(V(cyl_veloc),Drb)}
SYMATTR Value2 ic=0
SYMBOL bv 1584 144 R0
SYMATTR InstName B3
SYMATTR Value V=V(cyl_posn)<Dh
SYMBOL voltage 1008 432 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V8
SYMATTR Value {-Ag*Mp}
SYMBOL bv 1008 288 R0
SYMATTR InstName B4
SYMATTR Value V=if(V(cyl_posn)<Drb,-(V(cyl_posn)-Drb)*Krb,0)
SYMBOL bv -32 16 R0
SYMATTR InstName B5
SYMATTR Value V=V(cyl_posn)<10m
SYMBOL local\\Monostable 128 -16 R0
WINDOW 39 20 66 Left 2
SYMATTR InstName X2
SYMATTR SpiceLine width=Tco
SYMBOL bv -112 352 R0
SYMATTR InstName B6
SYMATTR Value V=(V(cyl_veloc)<0.1)&(V(cyl_posn)>50m)
SYMBOL bv 1008 -288 R0
SYMATTR InstName B7
SYMATTR Value V=idt(V(net_force))/Mp
SYMBOL voltage 1088 176 R0
WINDOW 3 35 62 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V3
SYMATTR Value {Patm}
SYMBOL bv 1744 -336 R0
SYMATTR InstName B8
SYMATTR Value V=idt(I(V2))/time
TEXT 680 216 Left 2 ;steam expansion
TEXT 328 256 Left 2 ;exh valve
TEXT 464 -104 Left 2 ;inlet valve
TEXT -792 -424 Left 2 !.param Ahp=2.5e-4; area of hydraulic piston in m^2
TEXT -792 -456 Left 2 !.param Asp=.005; area of steam piston in m^2
TEXT -792 248 Left 2 !.model SteamIn SW(Ron=Rsv, Vt=0.5)
TEXT -792 280 Left 2 !.model SteamExh SW(Ron=Rsv, Vt=0.5)
TEXT -792 312 Left 2 !.model OutCheck D(Ron=1 Roff=1e16)
TEXT -792 344 Left 2 !.model SuctionCheck D(Ron=1)
TEXT -792 376 Left 2 !.model SuctionValve SW(Ron=1, Vt=0.5)
TEXT -792 424 Left 2 !.tran 2 uic
TEXT -792 -392 Left 2 !.param Mp=40; moving mass of piston in kg
TEXT -792 -360 Left 2 !.param Pb=400kPa; boiler pressure (gage) in Pa
TEXT -792 -264 Left 2 !.param Patm=100kPa; atm pressure in Pa
TEXT -792 -296 Left 2 !.param Pc=-50kPa; condenser pressure (gage) in Pa
TEXT -792 -232 Left 2 !.param Pacc=10MegPa; hydraulic accumulator pressure (gage) in Pa
TEXT -792 -200 Left 2 !.param Ag=9.86; accel of gravity in m/s^2
TEXT 1048 480 Left 2 ;piston deadweight
TEXT 1048 344 Left 2 ;piston bottom rebound stop
TEXT -792 -168 Left 2 !.param Drb=10mm; rebound stop distance in m
TEXT -792 -136 Left 2 !.param Krb=1meg; rebound spring stiffness in N/m
TEXT -792 -104 Left 2 !.param gam=1.3; adiabatic expansion exponent (gamma)
TEXT 288 -232 Right 2 ;Boiler\npressure
TEXT 512 416 Left 2 ;Condenser\npressure
TEXT 1192 40 Left 2 ;hydraulic fluid\nvolumetric\ndisplacement
TEXT 1616 280 Left 2 ;hydraulic free-flow\ncontrol logic
TEXT 1480 -424 Left 2 ;hydraulic output
TEXT 648 32 Left 2 ;steam side pressure
TEXT 1080 -96 Left 2 ;hydraulic side pressure
TEXT -16 -120 Left 2 ;inlet valve\ncontrol logic
TEXT -48 384 Left 2 ;exhaust valve\ncontrol logic
TEXT -792 -328 Left 2 !.param Rbp=2.3; steam density at boiler pressure in kg/m^3
TEXT -792 -72 Left 2 !.param Rsv=2000; pressure drop at steam valves in Pa/(kg/s)
TEXT -792 -40 Left 2 !.param Tco=40ms; inlet valve cutoff in seconds
TEXT 504 104 Left 2 ;"current" = mass flow in kg/s
TEXT 688 152 Left 2 ;"charge" Q in kg
TEXT -792 -8 Left 2 !.param Dh=100mm; hydraulic engagement distance in m
TEXT 8 -616 Left 5 ;Vertical Free-Piston Steam Engine with Hydraulic Load
TEXT 1264 -560 Left 2 ;20-Nov-2011