Bubble Dynamics and Nucleate Pool Boiling of Natural Convection

  • سال انتشار: 1401
  • محل انتشار: فصلنامه انرژی و محیط زیست ایران (ایرانیکا)، دوره: 13، شماره: 4
  • کد COI اختصاصی: JR_IJEE-13-4_008
  • زبان مقاله: انگلیسی
  • تعداد مشاهده: 121
دانلود فایل این مقاله

نویسندگان

S. Bagheri

Department of Mechanical Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran

S. A. A. Oloomi

Department of Mechanical Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran

S. A. A. Mirjalily

Department of Mechanical Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran

A. Zare-Shahabadi

Department of Mechanical Engineering, Technical and Vocational University (TVU), Tehran, Iran

چکیده

The phenomenon of nuclear boiling has always been recognized suitable for heat transfer between different boiling regimes. Study on boiling is considered as a new field which meets different research and industrial needs such as heat transfer in nuclear reactors, cooling units, rocket motors, electronic equipment cooling, batteries, etc. In this study, a chamber with immiscible fluid, water, steam, and air, having a side wall with uniform heat flux has been studied in ۳D. To do so, we first considered the prediction of the heat flux interval for which the boiling occurs in the form of nuclear boiling. In this study, two-phase fluid volume (VOF) approach was used for modelling boiling on the vertical wall and two-phase flow. In this research, Ansys software package was used for numerical modelling and numerical simulation. Distribution of the velocity field follows more uniform pattern in dimensionless heights less than ۰.۹. In this study, bubbles are only present near a wall with heat flux that has a lower Rayleigh number. Also, existence of these bubbles on the wall, which prevents fluid infiltration, affects vortices caused by natural convection. However, the general and uniform patterns of vortices remain unchanged in most part of the fluid, which is because of the limited amount of bubbles near the wall with heat flux. Natural convection increases the height of fluid inside the chamber, which leads to the formation of stronger vortices at a dimensionless height of ۰.۹ that has a high Raleigh number due to high heat flux. In this case, the continuous use of heat flux gives rise to the production of bubbles over time.

کلیدواژه ها

Bubble diameter, bubble production frequency, nuclear boiling, Volume fraction

اطلاعات بیشتر در مورد COI

COI مخفف عبارت CIVILICA Object Identifier به معنی شناسه سیویلیکا برای اسناد است. COI کدی است که مطابق محل انتشار، به مقالات کنفرانسها و ژورنالهای داخل کشور به هنگام نمایه سازی بر روی پایگاه استنادی سیویلیکا اختصاص می یابد.

کد COI به مفهوم کد ملی اسناد نمایه شده در سیویلیکا است و کدی یکتا و ثابت است و به همین دلیل همواره قابلیت استناد و پیگیری دارد.