Vicente Dolz Ruiz vidolrui@mot.upv.es 1

ASME ORC 2017 4th International Seminar on ORC Power Systems

13-15 September 2017, Milano, Italy

Vicente Dolz Ruiz vidolrui@mot.upv.es

DYNAMIC MODELING OF AN ORGANIC RANKINE CYCLE TO RECOVER WASTE

HEAT FOR TRANSPORTATION VEHICLES

LMS Imagine.Lab Amesim

Vicente Dolz Ruiz vidolrui@mot.upv.es

ORC facility. Mock up

expander

brake

expander vessel

boiler

pump

2

IC engine

FS

T T

FS

T P

T P

Evaporator

Brake

Electric motor & freq. var.

Exhaust gas

P

T P

T P

Condenser

T P

T

P

Expander T

T

Tank

Expander vessel

T

T

FS

Cooling water

Pump

Ethanol

T

FS

Temp. sensor

Pres. sensor

Flow sensor

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 3

Swash-plate characteristics

Working fluid ethanol

Pistons working 3

Bore 40 mm

Stroke 31 mm

Maximum expander speed 4500 rpm

ORC facility. Expander

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 4

ORC facility. Working points

Ford Explorer 2 liter turbocharged gasoline engine

Point 84km/h

Point 114km/h

Vehicle speed (km/h) 84 114

Engine speed (rpm) 2000 2700

Fuel power (kW) 69.6 119.1

Engine power output (kW) 22.2 38.5

Inlet temperature of the exhaust gas (°C) 526 646

Mass flow exhaust gas (g/s) 24 41

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 5

Model description. ORC

LMS Imagine.Lab Amesim

Vicente Dolz Ruiz vidolrui@mot.upv.es 6

2000 rpm 3000 rpm

Point 114km/h (25 kW heat power)

Model description. ORC validation

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 7

Point 114km/h (25 kW heat power)

Model description. ORC validation

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 8

LMS Imagine.Lab Amesim

Model description. Vehicle model + ORC

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 9

0

25

50

75

100

125

150

-30

0

30

60

90

120

150

0 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375

velo

city

[km

/h]

torq

ue [N

m]

time [s]

engine torque total torque (engine +ORC) vehicle velocity

0

25

50

75

100

125

150

-30

0

30

60

90

120

150

300 305 310 315 320 325 330 335 340 345 350 355 360

velo

city

[km

/h]

torq

ue [N

m]

time [s]

Extra-urban part of NEDC

NEDC modeling. Vehicle model + ORC

• ORC facility • Model description • NEDC modeling • Conclusions

Gear changes

Vicente Dolz Ruiz vidolrui@mot.upv.es 10

NEDC modeling. Vehicle model + ORC

0

25

50

75

100

125

150

180

200

220

240

260

280

300

300 305 310 315 320 325 330 335 340 345 350 355 360

velo

city

[km

/h]

bsfc

[g/k

Wh]

bsfc without ORC

bsfc with ORC

vehicle velocity

-15

-10

-5

0

5

300 305 310 315 320 325 330 335 340 345 350 355 360

bsfc

diff

eren

ce [%

]

time [s]

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 11

Conclusions

• A vehicle model to reproduce the vehicle behavior has been coupled to an ORC system model with ethanol as working fluid. In this model, the engine shaft is directly coupled to the expander shaft to estimate the fuel consumption reduction during the extra-urban part of the NEDC.

• The ORC system is more efficient on extra-urban conditions (vehicle speeds higher than 50 km/h). At 120 km/h bsfc can be reduced a 10% by using an ORC. On the other hand, on urban driving conditions (speeds below 50km/h), these systems have not enough power to start the cycle (to evaporate the ethanol).

• This model can be used in complex engine layouts to optimize different strategies. In case of hybrid vehicles the ORC mechanical power can be used to increase the engine shaft torque or to recharge the batteries. The strategy to answer this question could be optimized by using similar models.

• ORC facility • Model description • NEDC modeling • Conclusions

Vicente Dolz Ruiz vidolrui@mot.upv.es 12

Thanks for your

attention