Vol 6, No 6 (2015) > Mechanical Engineering >

Experimental Investigation of Slugging as Initiating Water Hammer Phenomenon through Indirect Contact Steam Condensing in a Horizontal Pipe Heat Exchanger

Sukamta Sukamta, Indarto Indarto, Purnomo Purnomo, Tri Agung Rohmat

 

Abstract:

Slugging as a water hammer initiator is a fascinating topic because it
has a strategic impact on equipment safety in industrial systems, i.e. pressurized water reactors (PWR), heat exchangers, etc. The present research’s objective
was to investigate slugging as initiating the water hammer phenomenon through indirect
contact steam condensing in a horizontal pipe heat exchanger. The experiment apparatus used in the present
experimental study consisted of an inner annulus pipe made of copper (din
= 17.2 mm, do = 19 mm) with a length of 1.8 m and an outer annulus pipe
of galvanized iron (din = 108.3 mm, do = 114. 3 mm) with
a length of 1.6 m. The tested liquid was water. The experiments were conducted
at a static pressure of Ps = 108.825 kPa and the temperature of T
= 119.7°C. The
obtained experimental data of temperature and differential pressure fluctuations were analyzed
using statistical analysis. The results were as follows: 1) the flow pattern area of non-slugging
(stratified and wavy flow), transition (wavy-slug flow), and slugging (slug and
large-slug) were determined, with the transition flow pattern of slug and
large-slug defined as initiating water hammer; 2) transition area ranges for the
wavy-slug flow pattern are from ṁco=1´10-1 kg/s to ṁco=6´10-1 kg/s for ṁst=6´10-3 kg/s to ṁst=7.5´10-3 kg/s, and
co< 3´10-1 kg/s for ṁst=8´10-3 kg/s to ṁst=9´10-3 kg/s.
These obtained data are very important in order to develop a database for the input
of an early warning system design in a safe, two-phase flow installation piping
system during steam condensation.

Keywords: Heat exchanger; Horizontal pipe; Slugging; Steam condensation; Two-phase flow

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References


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