Effects of an Exhaust Heat Recovery System on Performance Characteristics of a Forklift Truck

  • Man-Woong Heo
  • Suk-Jung Bae
  • Joo-Yeong Jeong
  • Han-Sung Yoo
  • Seung-Uk Park
  • Hyung-Seok HeoEmail author


Construction equipment has consumed a lot of energy with a high workload compared to commercial vehicles of the same class. So, fuel efficiency is one of the important indicators of merchantability of the construction equipment. Especially, because forklift has been generally used only when necessary, the work has been carried out without adequate warm-up. So, not only the thermal efficiency of the engine of the construction equipment has deteriorated but also the sufficient fluidity of auto transmission fluid and hydraulic fluid have been hardly able to secure. Therefore, the exhaust heat recovery (EHR) system which consists of exhaust heat recovery unit and auto-transmission fluid (ATF) heater has been developed to improve the fuel economy of forklift by recovering the waste heat of exhaust gas. The performance tests of a 4.5 ton forklift have been carried out to evaluate the effects of exhaust heat recovery system on the fuel economy under the VDI fuel consumption drive cycle. It has found that the fuel consumption of a 4.5 ton forklift can be reduced through the fast warm-up of the auto-transmission fluid by recovering the waste heat of exhaust gas.

Key Words

Forklift Fast warm-up ATF heater EHR system Fuel consumption 



auto transmission


auto-transmission fluid


computational Fluid Dynamics


pressure drop


exhaust gas


exhaust heat recovery


height of core


hydraulic fluid


height of fin


off-set length of fin


pitch of fin


heat transfer


thickness of fin


thickness of housing


thickness of tube


width of core


width of tube


side gap


tube gap


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The research was supported by a grant (No. 20172020108590) from the Korea Institute of Energy Technology Evaluation and Planning (KETEP), that is funded by the Ministry of Trade, Industry and Energy.


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Copyright information

© KSAE 2019

Authors and Affiliations

  • Man-Woong Heo
    • 1
    • 2
  • Suk-Jung Bae
    • 3
  • Joo-Yeong Jeong
    • 1
  • Han-Sung Yoo
    • 1
  • Seung-Uk Park
    • 4
  • Hyung-Seok Heo
    • 3
    Email author
  1. 1.Eco-Energy GroupKorea Construction Equipment Technology InstituteJeonbukKorea
  2. 2.Coastal Development and Ocean Energy Research CenterKorea Institute of Ocean Science and TechnologyBusanKorea
  3. 3.Thermal Fluid Technology Research TeamKorea Automotive Technology InstituteChungnamKorea
  4. 4.Advanced Development TeamHaesong Engineering Co., LTD.ChungbukKorea

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