Experiments and CFD simulation of an air-conditioned tractor cabin for thermal comfort of tractor operators in Pakistan

Mahmood Riaz; Muhammad Hamid Mahmood; Muhammad Nauman Ashraf; Muhammad Sultan; Uzair Sajjad; Khalid Hamid; Muhammad Farooq; Faming Wang

doi:10.1016/j.heliyon.2023.e23038

Experiments and CFD simulation of an air-conditioned tractor cabin for thermal comfort of tractor operators in Pakistan

Heliyon. 2023 Nov 29;9(12):e23038. doi: 10.1016/j.heliyon.2023.e23038. eCollection 2023 Dec.

Authors

Mahmood Riaz¹, Muhammad Hamid Mahmood¹, Muhammad Nauman Ashraf¹, Muhammad Sultan¹, Uzair Sajjad², Khalid Hamid³, Muhammad Farooq⁴, Faming Wang⁵

Affiliations

¹ Department of Agricultural Engineering, Faculty of Agricultural Sciences & Technology, Bahauddin Zakariya University, Multan, 60800, Pakistan.
² Department of Energy and Refrigerating Air-Conditioning Engineering, National Taipei University of Technology, Taipei, 10608, Taiwan.
³ Department of Energy and Process Engineering, Norwegian University of Science and Technology, 7491, Trondheim, Norway.
⁴ Department of Mechanical Engineering, University of Engineering and Technology, 39161, Lahore, Pakistan.
⁵ Department of Biosystems, KU Leuven, Leuven, 3001, Belgium.

Abstract

Tractors are manufactured without air-conditioned cabins in Pakistan. This leads to thermal discomfort for tractor operators working under direct solar exposure. Therefore, this study aimed to design and install an air-conditioned cabin on a tractor. Experiments were undertaken to evaluate the installed cabin performance under two scenarios i.e., conventional (S-I) and enhanced (S-II) air distribution. Computational fluid dynamics (CFD) simulations were used to analyze airflow and calculate thermal comfort indices. The results showed that the air-conditioned cabin attained optimum thermal conditions under the enhanced air distribution scenario (S-II). In this scenario, the inside cabin temperature was an average of 27.4 °C, compared with 30.4 °C in S-I. The relative humidity remained similar in both scenarios, around 53 %. The temperature difference between the cabin and the ambient environment was 11.09 °C in S-II, aligning with the thermal comfort conditions outlined in ISO 14269-2. Furthermore, the CFD simulations showed a predicted mean vote (PMV) index of 0.61 and the percentage people dissatisfied (PPD) index of 26.5 %. These results also confirm the provision of optimum thermal conditions for operator inside the cabin. The simulations also demonstrated good agreement with experimental data, with a small difference in air temperature (2 °C) and relative humidity (5.8 %). In the light of these findings, this study recommends installation of air-conditioned cabin on tractors with enhanced air distribution (S-II) in Pakistan to improve thermal comfort of operators.

Keywords: Air-conditioning; CFD simulation; Design and development; Human thermal comfort; Tractor cabin.