Experimental study on flow modes and transient characteristics in low-pressure equal-height-difference natural circulation system

An experimental study was conducted on the operation of a “once-through” thermosiphon system. This new type of natural circulation system, unlike the standard thermosiphon system, heats the collector fluid in one pass without any recirculation. An electrically heated manifold was used to simulate the useful solar gain. Power was varied with time in 22 half-hour increments to simulate the actual daily useful solar gain. The time-dependent responses of the system in terms of temperatures and mass flow rates were recorded and plotted. The response time for mass flow and temperature to approach steady state varied directly with the size of the power step. Two experiments were conducted; one which tracked mass flows and outlet temperatures for variable useful solar gains, and a second which tracked mass flows at constant outlet temperature for variable useful solar gains.

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1205 An Experimental Study of Two-Phase Natural Circulation System Cooling a Pin Type Finned Heating Surface

The Proceedings of Conference of Kansai Branch ◽

10.1299/jsmekansai.2005.80._12-9_ ◽

2005 ◽

Vol 2005.80 (0) ◽

pp. _12-9_-_12-10_

Author(s):

Mitsunari MASAKA ◽

Hiroaki KUTSUNA ◽

Yoshiki NOGUCHI ◽

Yoichi SHIOMI ◽

Shigeyasu NAKANISHI

Keyword(s):

Experimental Study ◽

Natural Circulation ◽

Heating Surface ◽

Circulation System ◽

Two Phase

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An experimental study of two-phase flow instability in a multi-loop natural circulation system

Annals of Nuclear Energy ◽

10.1016/j.anucene.2019.107269 ◽

2020 ◽

Vol 139 ◽

pp. 107269

Author(s):

Zahraddeen Abbati ◽

Jiarui Chen ◽

Kun Cheng ◽

Fulong Zhao ◽

Fenglei Niu ◽

...

Keyword(s):

Experimental Study ◽

Two Phase Flow ◽

Flow Instability ◽

Natural Circulation ◽

Circulation System ◽

Phase Flow ◽

Two Phase

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Advanced Natural Circulation Reduced Order Model With Inclined Channel for Low Pressure Conditions

Volume 6A: Thermal-Hydraulics and Safety Analyses ◽

10.1115/icone26-81238 ◽

2018 ◽

Author(s):

René Manthey ◽

Alexander Knospe ◽

Carsten Lange ◽

Christoph Schuster ◽

Antonio Hurtado

Keyword(s):

Reference Model ◽

Nonlinear Dynamical Systems ◽

Natural Circulation ◽

Dynamical Behavior ◽

Low Pressure ◽

Reduced Order Model ◽

Circulation System ◽

Order Model ◽

Two Phase ◽

Reduced Order

Natural circulation with two-phase flow is a nonlinear dynamical systems, which can show a very complex and strange behavior under specific conditions. The application of stability analysis requires a large computational effort and is cumbersome in case of prediction the dynamical behavior by system codes alone. Therefore, model order reduction techniques are used to compensate this disadvantage by coupling with a bifurcation code such as MatCont. A reduced order model is derived by employing the POD-method to analyze the stability landscape of a low pressure natural circulation system representing passive safety systems such as the containment cooling condenser. The required full order model contains a classical natural circulation loop with a heated section and a riser. The two-phase region is modeled by a drift-flux mixture model. The reliability of the FOM is investigated by comparison with a reference model by the validated system code ATHLET.

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Numerical study of nuclear coupled two-phase flow instability in natural circulation system under low pressure and low quality

Nuclear Engineering and Design ◽

10.1016/j.nucengdes.2011.08.074 ◽

2011 ◽

Vol 241 (12) ◽

pp. 4972-4977 ◽

Cited By ~ 6

Author(s):

Jianhua Wang ◽

Yuliang Sun ◽

Jianjun Wang ◽

E. Laurien

Keyword(s):

Two Phase Flow ◽

Flow Instability ◽

Numerical Study ◽

Natural Circulation ◽

Low Pressure ◽

Circulation System ◽

Phase Flow ◽

Two Phase

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Advanced Natural Circulation Reduced-Order Model With Inclined Channel for Low Pressure Conditions

Journal of Nuclear Engineering and Radiation Science ◽

10.1115/1.4044846 ◽

2020 ◽

Vol 6 (2) ◽

Author(s):

René Manthey ◽

Alexander Knospe ◽

Carsten Lange ◽

Christoph Schuster ◽

Antonio Hurtado

Keyword(s):

Reference Model ◽

Nonlinear Dynamical Systems ◽

Natural Circulation ◽

Dynamical Behavior ◽

Low Pressure ◽

Reduced Order Model ◽

Circulation System ◽

Order Model ◽

Two Phase ◽

Reduced Order

Abstract Natural circulation with two-phase flow is a nonlinear dynamical systems, which can show a very complex and strange behavior under specific conditions. The application of stability analysis requires a large computational effort and is cumbersome in case of prediction the dynamical behavior by system codes alone. Therefore, model-order reduction techniques are used to compensate this disadvantage by coupling with a bifurcation code such as MatCont. A reduced-order model is derived by employing the proper orthogonal decomposition (POD) to analyze the stability landscape of a low pressure natural circulation system representing passive safety systems such as the containment cooling condenser. The required full-order model contains a classical natural circulation loop with a heated section and a riser. The two-phase region is modeled by a drift–flux mixture model. The reliability of the full-order model is investigated by comparison with a reference model by the validated system code ATHLET.

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