1. School of Engineering and Built Environment, Edinburgh Napier Univ., Edinburgh, United Kingdom; on leave from Faculty of Engineering, Mechanical Engineering Dept., Omar Al-Mukhtar Univ., Libya (corresponding author).
2. Faculty of Engineering and Architecture, Dept. of Mechanical Engineering, Abant Izzet Baysal Univ., 14280, Bolu, Turkey.
3. School of Engineering and Built Environment, Edinburgh Napier Univ., Edinburgh, United Kingdom.