Thermosyphon system: A simple engine cooling system based on the natural convection caused by the difference in densities of the hot and the cold regions of the cooling water; is now obsolete. Related posts: Personnel Management Operative Functions Administrative Role of PM Competency HR Management Role Change Personnel Policies Personnel Procedures Appealed Policies Implied Policies Specific Policies Personnel records Research Pure research Personnel research Attitude or Opinion Survey Turnover Secondary research Applied research Personnel audit Read more articles Previous PostThermal Efficiency – Indicated thermal efficiency or brake thermal efficiency Next PostThree-way converter