Energy Efficiency

, Volume 11, Issue 4, pp 877–891

# Analysis of different scenarios of car paint oven redesign to achieve desired indoor air temperature

Original Article

## Abstract

Car paint ovens consume a lot of energy within the automobile factory. For this reason, proper selection or design of this unit can yield substantial reduction in costs. In addition, car paint ovens that operate in existing factories quite often cannot assure adequate indoor air temperature and they need to be redesigned. In such an instance, simulating the oven operation is very important as it allows optimal selection of parameters that need to be changed in order that paint oven meets the requirements. In this paper, mathematical model for simulation of energy flows in car paint oven is presented. The model can be used to easily analyze which variables and to what extent affect the operating parameters (such as air temperature or car body temperature) of car paint oven, that could help designers to select optimal scenario for designing new or redesigning existing car paint ovens in order to achieve desired indoor air temperature.

## Keywords

Car paint oven Mathematical model Optimal scenario Simulation Energy efficiency Energy saving

## Nomenclature

$$\Delta \dot {m}_2$$

mass flow rate of fresh and exhausted air (kg/s)

$$\dot {m}_2$$

mass flow of air through heating unit (kg/s)

$$\dot {m}_3$$

mass flow rate of car bodies through the oven (kg/s)

$$\dot {m}_4$$

mass flow rate of carrier through the oven (kg/s)

$$\dot {Q_1}$$

heat in the air flow leaving the heating unit (W)

$$\dot {Q_2}$$

heat in the air flow entering the car paint oven (W)

$$\dot {Q_3}$$

heat that is transferred to car bodies (W)

$$\dot {Q_4}$$

heat that is transferred to carrier (W)

$$\dot {Q_g}$$

heat losses in heating unit (W)

$$\dot {Q}$$

heat of condensation (W)

$$\dot {Q}^{1}_{\Delta \dot {m}}$$

heat in the exhausted air (W)

$$\dot {Q}^{2}_{\Delta \dot {m}}$$

heat needed to heat the fresh air (W)

$$\dot {Q}_{01}$$

heat losses through the oven walls (W)

$$\dot {Q}_{02}$$

heat losses through the oven floor (W)

$$\dot {Q}_{03}$$

heat losses due to inflow of cold air through the inlet and outlet doors of the oven (W)

$$\dot {Q}_{04}$$

heat losses due to evaporation of paint solvent (W)

$$\dot {Q}_{05}$$

heat losses due to evaporation of water (W)

$$\dot {Q}_{0}$$

heat losses in car paint oven (W)

$$\dot {Q}_{g1}$$

heat losses through air supply channel (W)

$$\dot {Q}_{g5}$$

heat losses through feedback channel (W)

Ag2

length of car paint oven (m)

c3

specific heat of car body material (J/kg⋅C)

c4

specific heat of carrier material (J/kg⋅C)

cp

specific heat of air (J/kg⋅C)

kg1

overall heat transfer coefficient for air supply channel walls (W/m2C)

kg3

overall heat transfer coefficient for paint layer at car body (W/m2C)

kg4

overall heat transfer coefficient for paint layer to be deposited on carrier (W/m2C)

kg5

overall heat transfer coefficient for feedback channel walls (W/m2C)

kR

overall heat transfer coefficient of heat exchanger (W/m2C)

Sg1

surface area of air supply channel walls (m2)

Sg3

surface area of all car bodies within the oven (m2)

Sg4

surface area of carrier within the oven (m2)

Sg5

surface area of feedback channel walls (m2)

SR

surface area of heat exchanger (m2)

t1i

air temperature at the inlet of mixing chamber (C)

t1i

air temperature at the inlet of heating unit (C)

t1o

air temperature at the exit of heating unit (C)

t2i

air temperature at the inlet of car paint oven (C)

t2o

air temperature at the exit of car paint oven (C)

t3i

inlet temperature of car body (C)

t3o

outlet temperature of car body (C)

t4i

inlet temperature of carrier (C)

t4o

outlet temperature of carrier (C)

ta

outer temperature (C)

ts

steam temperature (C)

## References

1. Akafuah, N., Poozesh, S., Salaimeh, A., Patrick, G., Lawler, K., Saito, K. (2016). Evolution of the automotive body coating processa review. Coatings, 6(2), 24. http://www.mdpi.com/2079-6412/6/2/24.
2. Ashrafizadeh, A., Mehdipour, R., Aghanajafi, C. (2012). A hybrid optimization algorithm for the thermal design of radiant paint cure ovens. Applied Thermal Engineering, 40, 56–63.
3. Boyd, G.A. (2014). Estimating the changes in the distribution of energy efficiency in the U.S. automobile assembly industry. Energy Economics, 42, 81–87. .
4. Boyd, G.A. (2017). Comparing the statistical distributions of energy efficiency in manufacturing: meta-analysis of 24 Case studies to develop industry-specific energy performance indicators (EPI). Energy Efficiency, 10, 1–22. .
5. Buczynski, R., Weber, R., Kim, R., Schwöppe, P. (2016). One-dimensional model of heat-recovery, non-recovery coke ovens. Part IV: Numerical simulations of the industrial plant. Fuel, 181, 1151–1161.
6. Behzad, E., Behdad, S., Wang, B. (2016). The evolution and future of manufacturing: A review. Journal of Manufacturing Systems, 39, 79–100. http://www.sciencedirect.com/science/article/pii/S0278612516300024.
7. Lujia, F., Mears, L., Beaufort, C., Schulte, J. (2016). Energy, economy, and environment analysis and optimization on manufacturing plant energy supply system. Energy Conversion and Management, 117, 454–465. .
8. Galitsky, C., & Worrell, E. (2008). Energy efficiency improvement and cost saving opportunities for the vehicle assembly industry: an energy star guide for energy and plant managers. An ENERGY STAR Guide for Energy and Plant Managers. Lawrence Berkeley National Laboratory, University of California: Berkeley, CA, USA, 2008. Available online: https://www.energystar.gov/ia/business/industry/LBNL-50939.pdf (accessed on 10 October 2016).
9. Geipel, C., & Stephan, P. (2005). Experimental investigation of the drying process of automotive base paints. Applied Thermal Engineering, 25(16), 2578–2590.
10. Guerrero, C.A., Wang, J., Li, J., Arinez, J., Biller, S., Huang, N., Xiao, G. (2011). Production system design to achieve energy savings in an automotive paint shop. International Journal of Production Research, 49(22), 6769–6785. .
11. Iglauer, O., & Zahler, C. (2014). A new solar combined heat and power system for sustainable automobile manufacturing. Energy Procedia, 48, 1181–1187. Proceedings of the 2nd International Conference on Solar Heating and Cooling for Buildings and Industry (SHC 2013). http://www.sciencedirect.com/science/article/pii/S1876610214003956.
12. Zinedine, K., Paton, J., Thompson, H., Kapur, N., Toropov, V. (2013). Optimisation of the energy efficiency of bread-baking ovens using a combined experimental and computational approach. Applied Energy, 112, 918–927. .
13. Zinedine, K., Paton, J., Thompson, H., Kapur, N., Toropov, V., Lawes, M., Kirk, D. (2012). Computational fluid dynamics (CFD) investigation of air flow and temperature distribution in a small scale bread-baking oven. Applied Energy, 89(1), 89–96. .
14. Uroš, K., Škerget, L., Ravnik, J. (2017). A numerical model of the shortbread baking process in a forced convection oven. Applied Thermal Engineering, 111, 6–8. http://linkinghub.elsevier.com/retrieve/pii/S1359431116322347.Google Scholar
15. Sazal, K., Zanganeh, J., Moghtaderi, B. (2016). A review on understanding explosions from methan-air mixture. Journal of Loss Prevention in the Process Industries, 40, 507–523. http://www.sciencedirect.com/science/article/pii/S0950423016300286.
16. Li, J., Uttarwar, R.G., Huang, Y. (2013). CFD-based modeling and design for energy-efficient VOC emission reduction in surface coating systems. Clean Technologies and Environmental Policy, 15(6), 1023–1032.
17. Sathit, N., Kittisupakorn, P., Suwatthikul, A. (2015). Enhancement of energy efficiency in a paint curing oven via CFD approach: Case study in an air-conditioning plant. Applied Energy, 156, 465–477. .
18. Oh, S.C., & Hildreth, A.J. (2014). Estimating the technical improvement of energy efficiency in the automotive industry-stochastic and deterministic frontier benchmarking approaches. Energies, 7(9), 6196–6222.
19. O’Reilly, C.J., Göransson, P., Funazaki, A., Suzuki, T., Edlund, S., Gunnarsson, C., Lundow, J.-O., Cerin, P., Cameron, C.J., Potting, J. (2016). Life cycle energy optimisation: A proposed methodology for integrating environmental considerations early in the vehicle engineering design process. Journal of Cleaner Production, 135, 750–759.
20. Pask, F., Sadhukhan, J., Lake, P., McKenna, S., Perez, E. B., Yang, A. (2014). Systematic approach to industrial oven optimisation for energy saving. Applied Thermal Engineering, 71(1), 72–77. .
21. Rao, P., & Teeparthi, S. (2011). A semi–computational method to predict body temperatures in an automotive paint bake oven. In ASME 2011 International Mechanical Engineering Congress and Exposition, 85–95. American Society of Mechanical Engineers.Google Scholar
22. Rao, P.P. (2013). A heat exchanger analogy of automotive paint ovens. Applied Thermal Engineering, 61(2), 381–392. .
23. Rao, P.P., & Gopinath, A. (2013). Energy savings in automotive paint ovens: a new concept of shroud on the carriers. Journal of Manufacturing Science and Engineering, 135(4), 1–9. http://manufacturingscience.asmedigitalcollection.asme.org/article.aspx?doi=10.1115/1.4024537.
24. Rivera, J.L., & Reyes-Carrillo, T. (2014). A framework for environmental and energy analysis of the automobile painting process. Procedia CIRP, 15, 171–175. .
25. Roelant, G.J, Kemppainen, A.J, Shonnard, D.R. (2004). Assessment of the automobile assembly paint process for energy, environmental, and economic improvement. Journal of Industrial Ecology, 8(1-2), 173–191.
26. Streitberger, H.-J., & Dossel, K.-F. (2008). Automotive Paints and Coatings, 2nd edn., (p. 1002). Weinheim: Wiley-VCH Verlag GmbH & Co. KGaA. https://www.scopus.com/inward/record.uri?eid=2-s2.0-84887612827&doi=10.
27. Svejda, P. (2011). Designing an automotive paint shop for optimal flexibility and efficiency. Metal Finishing, 109(8), 23–26. .
28. Wu, Y.H., Surapaneni, S., Srinivasan, K., Stibich, P. (2014). Automotive vehicle body temperature prediction in a paint oven. SAE Technical Paper 2014-01-0644. SAE International. .
29. Yu, G. (2013). Simulation of automotive paint curing process in an oven. Metal Finishing, 111(2), 18–22. http://linkinghub.elsevier.com/retrieve/pii/S0026057613701570.
30. Zahler, C., & Iglauer, O. (2012). Solar process heat for sustainable automobile manufacturing. Energy Procedia, 30, 775–782. http://www.sciencedirect.com/science/article/pii/S1876610212016049.