NUMERICAL STUDY EFFECT OF THROAT SHAPE TO ENERGY DISSIPATION IN WATER JET PUMP VIA ENTROPY GENERATION ANALYSIS Muhammad Penta Helios (*,a, b, c), Achmad Maswan (c), Andhy Muhammad Fathoni (c), Himawan Sutriyanto (c), Wanchai Asvapoositkul (d)4
(a) The Joint Graduate School of Energy and Environment, King Mongkut^s University of Technology Thonburi, Bangkok, 10140, Thailand
(b) Center of Excellence on Energy Technology and Environment, PERDO, King Mongkut^s University of Technology Thonburi, Bangkok, 10140, Thailand
(c) Laboratory of Thermodynamics, Engines and Propulsion Technology, Agency for the Assesment and Application Technology (BPPT), Serpong, 15314, Indonesia
(d) Department of Mechanical Engineering, Faculty of Engineering, King Mongkut^s University of Technology Thonburi, Bangkok, 10140, Thailand
Abstract
A numerical study of energy dissipation due to throat shape was carried out from entropy generation perspective. This study was aimed to analyze source of energy dissipation in term of entropy generation in the throat section of water jet pump by varying throat-entry angle, which started from throat-entry to middle throat length of original constant area of throat. The original throat shape had been varied from 1º to 4º, which represented combination of constant pressure and constant area shape of throat. The results concluded that the changes of throat-entry angle increased the entropy generation rate significantly, which corresponded to jet pump performance reduction. This occurred due to recirculation flow phenomena prior entrance to constant area of throat. Furthermore, an improvement had been applied by reducing the middle section of throat diameter about 12.3%, which known as continuous momentum rate change throat. The jet pump performance increased about 3.5% with corresponding to decreased entropy generation about 11.7%.
Keywords: Energy dissipation, entropy generation, water jet pump, throat-entry angle.
Topic: Symposium on Advance of Sustainable Engineering