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Title: Nucleate boiling of water in twisted-tape swirled flow

Abstract

This paper analyzes nucleate boiling in twisted-tape swirled water flow. The transverse flow velocity in the wall region, generated by the density gradient and acceleration, is estimated. It is concluded that the turbulence has a significant effect on the growth of vapor bubbles, decreasing the rate of nucleate boiling without simultaneously increasing the convective component to compensate for this effect.

Authors:
; ; ;  [1]
  1. (Polzunov Boiler and Turbine Inst., Leningrad (SU))
Publication Date:
OSTI Identifier:
5336894
Resource Type:
Journal Article
Resource Relation:
Journal Name: Heat Transfer - Soviet Research; (United States); Journal Volume: 22:6
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; WATER; NUCLEATE BOILING; BUBBLE GROWTH; TURBULENT FLOW; VORTEX FLOW; BOILING; FLUID FLOW; HYDROGEN COMPOUNDS; OXYGEN COMPOUNDS; PHASE TRANSFORMATIONS 420400* -- Engineering-- Heat Transfer & Fluid Flow

Citation Formats

Kudryavtsev, I.S., Lekakh, B.M., Paskar, B.L., and Fedorovich, Y.D. Nucleate boiling of water in twisted-tape swirled flow. United States: N. p., 1990. Web.
Kudryavtsev, I.S., Lekakh, B.M., Paskar, B.L., & Fedorovich, Y.D. Nucleate boiling of water in twisted-tape swirled flow. United States.
Kudryavtsev, I.S., Lekakh, B.M., Paskar, B.L., and Fedorovich, Y.D. 1990. "Nucleate boiling of water in twisted-tape swirled flow". United States. doi:.
@article{osti_5336894,
title = {Nucleate boiling of water in twisted-tape swirled flow},
author = {Kudryavtsev, I.S. and Lekakh, B.M. and Paskar, B.L. and Fedorovich, Y.D.},
abstractNote = {This paper analyzes nucleate boiling in twisted-tape swirled water flow. The transverse flow velocity in the wall region, generated by the density gradient and acceleration, is estimated. It is concluded that the turbulence has a significant effect on the growth of vapor bubbles, decreasing the rate of nucleate boiling without simultaneously increasing the convective component to compensate for this effect.},
doi = {},
journal = {Heat Transfer - Soviet Research; (United States)},
number = ,
volume = 22:6,
place = {United States},
year = 1990,
month = 1
}
  • This paper presents experimental data on the critical heat flux (CHF) in twisted-tape-inserted tubes over a wide quality range of {minus}0.25 to 0.8. The influences of quality, twist ratio, mass velocity, and clearance between the twisted tape and tube inner wall on CHF were investigated. In the subcooled region, it was observed, using an infrared thermoviewer, that CHF was initiated locally at the wall near the twisted tape. Consequently, twisted tape insertion with small tape-well clearance decreased CHF to below the value of the empty tubes at a low flow rate. This decrease was found to be avoidable by adjustingmore » the clearance. In the net quality region, CHF of the twisted-tape-inserted tubes increased with increasing flow rate contrary to the case of the empty tubes. However, CHF in the net quality region was also decreased by insertion of twisted tapes with high twist ratio (loosely twisted tapes) at a very low flow rate.« less
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