Skip to main content

Thermodynamic and heat transfer analysis of heat recovery from engine test cell by Organic Rankine Cycle

Abstract

During manufacture of engines, evaluation of engine performance is essential. This is accomplished in test cells. During the test, a significant portion of heat energy released by the fuel is wasted. In this study, in order to recover these heat losses, Organic Rankine Cycle (ORC) is recommended. The study has been conducted assuming the diesel oil to be composed of a single hydrocarbon such as C12H26. The composition of exhaust gases (products of combustion) have been computed (and not determined experimentally) from the stoichiometric equation representing the combustion reaction. The test cell heat losses are recovered in three separate heat exchangers (preheater, evaporator and superheater). These heat exchangers are separately designed, and the whole system is analyzed from energy and exergy viewpoints. Finally, a parametric study is performed to investigate the effect of different variables on the system performance characteristics such as the ORC net power, heat exchangers effectiveness, the first law efficiency, exergy destruction and heat transfer surfaces. The results of the study show that by utilizing ORC, heat recovery equivalent to 8.85 % of the engine power is possible. The evaporator has the highest exergy destruction rate, while the pump has the lowest among the system components. Heat transfer surfaces are calculated to be 173.6, 58.7, and 11.87 m2 for the preheater, evaporator and superheater, respectively.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Abbreviations

Afr :

Frontal surface (m2) (Eq. 7)

Ai :

Inner surface (m2)

Ao :

Outer surface (m2)

Aop :

Heat transfer surface for each pass (m2) (Eq. 16)

Aph :

Preheater heat transfer surface (m2)

Atp :

Evaporator heat transfer surface (m2)

Ash :

Superheater heat transfer surface (m2)

Aw :

Wall surface (m2) (Eq. 20)

C:

Heat capacity ratio (Eq. 32)

Cmin :

The smaller value of heat capacity rate for hot and cold fluids (kW/K)

Cmax :

The larger value of heat capacity rate for hot and cold fluids (kW/K)

cp :

Specific heat at constant pressure (kJ/kg K)

Dh :

Flow passage hydraulic diameter (m) (Eq. 9)

Di :

Inner diameter of tubes (m)

EPC:

Exergy performance coefficient

E, S, F:

Correction factor (Eqs. 17, 29)

\( {\mathop {Ex}\limits^{ \cdot }}_{D} \) :

Exergy destruction rate (kW)

\( {\mathop {Ex}\limits^{ \cdot }}_{D,tot} \) :

Total exergy destruction rate (kW)

\( {\mathop {Ex}\limits^{ \cdot} }_{in} \) :

Rate of exergy transfer into a control volume (kW)

\( {\mathop {Ex}\limits^{ \cdot }}_{out} \) :

Rate of exergy transfer out of control volume (kW)

\( {\mathop {Ex}\limits^{ \cdot} }_{ch} \) :

Chemical exergy rate (kW)

\( {\mathop {Ex}\limits^{ \cdot }}_{ph} \) :

Physical exergy rate (kW)

G:

Mass flux (kg/m2 s) (Eq. 9)

h:

Enthalpy (kJ/kg)

h0 :

Enthalpy at dead (environmental) state (kJ/kg)

H:

Convective heat transfer coefficient (W/m2 K)

Hi :

Convective heat transfer coefficient at the inner surface (W/m2 K)

Ho :

Convective heat transfer coefficient at the outer surface (W/m2 K)

He :

Height of heat exchanger (m)

Hf0 :

Convective heat transfer coefficient for film boiling (W/m2 K)

Hnb :

Convective heat transfer coefficient the nuclear boiling (W/m2 K)

kf :

Fin thermal conductivity (W/m K)

\( \dot{m} \) :

Mass flow rate (kg/s)

\( \dot{m}_{exh} \) :

Exhaust gasses mass flow rate (kg/s) (Eq. 2)

\( \dot{m}_{ref} \) :

ORC fluid mass flow rate (kg/s) (Eq. 2)

Ncol :

Number of tubes in a column

Nrow :

Number of tubes in a row

Ntp :

Number of tubes in a pass

NTU:

Number of transfer units

NTUc.f. :

Number of transfer units for counter flow heat exchanger

Nui :

Nusselt number at the inner surface

Pr:

Prandtl number

\( \dot{Q} \) :

Heat transfer rate (kW)

\( \dot{q}_{act} \) :

Actual heat transfer rate (kW)

\( \dot{q}_{max} \) :

Maximum heat transfer rate (kW)

Rdi :

Dirty resistance at the inner surface (m2 K/W) (Eq. 20)

Rdo :

Dirty resistance at the outer surface (m2 K/W) (Eq. 20)

Rw :

Thermal resistance of wall (K/W)

Re:

Reynolds number

s:

Entropy (kJ/kg K)

s0 :

Entropy at dead (environmental) state (kJ/kg K)

St:

Stanton number

T:

Temperature (K)

T0 :

Environmental temperature (K)

Tc :

Condenser temperature (K)

Te :

Evaporator temperature (K)

Tpp :

Pinch point temperature (K)

Tsup :

Superheat temperature (K)

u:

Overall heat transfer coefficient (W/m2 K)

V:

Volume of heat exchanger (m3)

w:

Width (m)

\( \dot{W}_{net} \) :

Net output power (kW)

\( \dot{W}_{t} \) :

Power of ORC turbine (kW)

\( \dot{W}_{p} \) :

Power of ORC pump (kW)

xi :

Molar fraction

xl :

Longitudinal tube pitch (m)

xt :

Transverse tube pitch (m)

YD :

Exergy destruction ratio

α:

Correction factor

β :

Fin area to total heat transfer area of heat exchanger

σ:

Minimum free flow area to frontal area

μ:

Viscosity (kg/m s)

ρ:

Density (kg/m3)

η:

Efficiency (%)

ηf :

Efficiency of a single fin (%)

ηo :

Overall surface efficiency (%)

δf :

Fin thickness (m)

\( \Delta T_{LMTD} \) :

Log mean temperature difference (K)

ε:

Effectiveness (%)

1, 2, 3, 4, 5, 6:

State points for the R11

a, x, y, b:

State points for the exhaust gas

References

  1. Abusoglu A, Kanoglu M (2008) First and second law analysis of diesel engine powered cogeneration systems. Energy Convers Manage 49:2026–2031

    Article  Google Scholar 

  2. Schuster A, Karellas S, Kakaras E, Spliethoff H (2009) Energetic and economic investigation of organic Rankine cycle applications. Appl Therm Eng 29:1809–1817

    Article  Google Scholar 

  3. http://www.turboden.it

  4. Drescher U, Bruggemann D (2007) Fluid selection for the organic Rankine cycle (ORC) in biomass power and heat plants. Appl Therm Eng 27:223–228

    Article  Google Scholar 

  5. Bruno JC, Lopez-Villad J, Letelier E, Romera S, Coronas A (2008) Modeling and optimization of solar organic rankine cycle engines for reverse osmosis desalination. Appl Therm Eng 28:2212–2226

    Article  Google Scholar 

  6. Kanoglu M, Bolatturk A (2008) Performance and parametric investigation of a binary geothermal power plant by exergy. Renew Energy 33:2366–2374

    Article  Google Scholar 

  7. Vaja I, Gambarotta A (2010) Internal combustion engine (ICE) bottoming with organic Rankine cycles (ORCs). Energy 35:1084–1093

    Article  Google Scholar 

  8. Bombarda P, Invernizzi CM, Pietra C (2010) Heat recovery from diesel engines: a thermodynamic comparison between Kalina and ORC cycles. Appl Therm Eng 30:212–219

    Article  Google Scholar 

  9. Kosmadakis G, Manolakos D, Papadakis G (2010) Parametric theoretical study of a two-stage solar organic Rankine cycle for RO desalination. Renew Energy 35:989–996

    Article  Google Scholar 

  10. Al-Sulaiman FA, Dincer I, Hamdullahpur F (2010) Exergy analysis of an integrated solid oxide fuel cell and organic Rankine cycle for cooling, heating and power production. J Power Sources 195:2346–2354

    Article  Google Scholar 

  11. Wang EH, Zhang HG, Fan BY, Ouyang MG, Zhao Y, Mu QH (2011) Study of working fluid selection of organic Rankine cycle (ORC) for engine waste heat recovery. Energy 36(5):3406–3418

    Article  Google Scholar 

  12. Kang SH (2012) Design and experimental study of ORC (organic Rankine cycle) and radial turbine using R245fa working fluid. Energy 41(1):514–524

    Article  Google Scholar 

  13. Rentizelas A, Karellas S, Kakaras E, Tatsiopoulos I (2009) Comparative technoeconomic analysis of ORC and gasification for bioenergy applications. Energy Convers Manage 50:674–681

    Article  Google Scholar 

  14. Gewald D, Karellas S, Schuster A, Spliethoff H (2012) Integrated system approach for increase of engine combined cycle efficiency. Energy Convers Manage 60:36–44

    Article  Google Scholar 

  15. Sun J, Li W (2011) Operation optimization of an organic Rankine cycle (ORC) heat recovery power plant. Appl Therm Eng 31:2032–2041

    Article  Google Scholar 

  16. Vélez F, Chejne F, Antolin G, Quijano A (2012) Theoretical analysis of a transcritical power cycle for power generation from waste energy at low temperature heat source. Energy Convers Manage 60:188–195

    Article  Google Scholar 

  17. He C, Liu C, Gao H, Xie H, Li Y, Wu S et al (2012) The optimal evaporation temperature and working fluids for subcritical organic Rankine cycle. Energy 38:136–143

    Article  Google Scholar 

  18. Wang EH, Zhang HG, Zhao Y, Fan BY, Wu YT, Mu QH (2012) Performance analysis of a novel system combining a dual loop organic Rankine cycle (ORC) with a gasoline engine. Energy 43:385–395

    Article  Google Scholar 

  19. Wang T, Zhang Y, Jie Z, Shu G, Peng Z (2012) Analysis of recoverable exhaust energy from a light-duty gasoline engine. Appl Therm Eng. doi:10.1016/j.applthermaleng.2012.03.025

  20. Hountalas DT, Mavropoulos GC, Katsanos C, Knecht W (2012) Improvement of bottoming cycle efficiency and heat rejection for HD truck applications by utilization of EGR and CAC heat. Energy Convers Manage 53:19–32

    Article  Google Scholar 

  21. Katsanos CO, Hountalas DT, Pariotis EG (2012) Thermodynamic analysis of a Rankine cycle applied on a diesel truck engine using steam and organic medium. Energy Convers Manage 60:68–76

    Article  Google Scholar 

  22. Zhang HG, Wang EH, Fan BY (2013) Heat transfer analysis of a finned-tube evaporator for engine exhaust heat recovery. Energy Convers Manage 65:438–447

    Article  Google Scholar 

  23. Wall G (1988) Exergy flows in industrial processes. Energy 13(2):197–208

    Article  Google Scholar 

  24. Abusoglu A, Kanoglu M (2009) Exergetic and thermoeconomic analyses of diesel engine powered cogeneration: part 2—application. Appl Therm Eng 29:242–249

    Article  Google Scholar 

  25. Kays WM, London AL (1984) Compact heat exchangers, vol 3. McGraw-Hill Book Company, New York

    Google Scholar 

  26. Bejan A, Kraus AD (2003) Heat transfer handbook. Wiley, Hoboken

    Google Scholar 

  27. Wang X, Wang H, Wang H (2011) Experimental study on evaporating heat transfer characteristics of HFC-245fa. J Wuhan Univ Technol 33(3):67–71

    Google Scholar 

  28. Ghiaasiaan SM (2008) Two-phase flow, boiling and condensation in conventional and miniature systems. Cambridge University Press, New York

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Naser Shokati.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Shokati, N., Mohammadkhani, F., Farrokhi, N. et al. Thermodynamic and heat transfer analysis of heat recovery from engine test cell by Organic Rankine Cycle. Heat Mass Transfer 50, 1661–1671 (2014). https://doi.org/10.1007/s00231-014-1375-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00231-014-1375-4

Keywords

  • Heat Exchanger
  • Convective Heat Transfer Coefficient
  • Heat Transfer Surface
  • Organic Rankine Cycle
  • Exergy Destruction