Pool boiling heat transfer enhancement on porous surface tube

Pool boiling heat transfer enhancement on porous surface tube 1 corresp first-author Corresponding author. E-mail address: liyong@hrbeu.edu.cn Corresponding author. E-mail address: liyong@hrbeu.edu.cn liyong@hrbeu.edu.cn 1 1 1 College of Nuclear Science and Technology, Harbin Engineering University, Heilongjiang 150001, China College of Nuclear Science and Technology, Harbin Engineering University, Heilongjiang 150001, China The passive residual heat removal exchanger (PRHR HX), which is a key equipment of the passive residual heat removal system, is installed in an elevated pool. Its heat transfer performance affects security and economics of the reactor, and boiling heat transfer in the liquid surrounding the exchanger occurs when the liquid saturation temperature exceeded. The smooth tubes, which are widely used as heat transfer tubes in PRHR HX, can be replaced by some enhanced tubes to improve the boiling heat transfer capability. In this paper, the pool boiling heat transfer characteristics of smooth tube and a machined porous surface tube are investigated by using high-pressure steam condensing inside tube as heating source. Compared with smooth tube, the porous surface tube considerably enhances the boiling heat transfer, and shortens the time significantly before reaching the liquid saturation temperature. Its boiling heat transfer coefficient increases from 68% to 75%, and the wall superheat decreases by 1.5ºC. Combining effect of condensation inside tube with boiling outside tube, the axial wall temperatures of heat transfer tube are neither uniform nor linear distribution. Based on these investigations, enhance mechanism of the porous surface tube is analyzed. Pool boiling Porous surface tube Enhanced heat transfer References Nayak A , Sinha R . Progress Nucl Energy , 2007 , 49 : 486 - 498 . Progress Nucl Energy Schulz T . Nucl Eng Design , 2006 , 236 : 1547 - 1557 . Nucl Eng Design Janusz T , Cieśliński . Experiment Therm Fluid Sc , 2002 , 25 : 557 - 564 . Experiment Therm Fluid Sc Xuenong G , Huibin H , et al . Appl Therm Eng , 2009 , 29 : 3212 - 3217 . Appl Therm Eng Naehyun K . Kukwang C . Intern J Heat Mass Transfer , 2001 , 44 : 17 - 28 . Intern J Heat Mass Transfer Min D . Hwang G . et al . Intern J Heat Mass Transfer , 2009 , 52 : 2607 - 2613 . Intern J Heat Mass Transfer Satish N , Patel A , Maheshwari N , et al . International Atomic Energy Agency ( http://www.iaea.or.at/OurWork/ST/NE/NENP/)NPTDS/Downloads/SRCM_NCP_2005_AUG/sess3_phen1_vijayan.pdf . International Atomic Energy Agency Yanis C , Athanassios K . Current Opinion Colloid Interface Sci , 2001 , 6 : 208 - 216 . Current Opinion Colloid Interface Sci Chien L Webb R . Intern J Heat Mass Transfer , 1998 , 41 : 2183 - 2195 . Intern J Heat Mass Transfer 10.13538/j.1001-8042/nst.22.122-128 2010-07-18 2011-04-20 2021-01-19 2011 Nuclear Science and Techniques 02 22