Abstract
Full text of publication follows: Knowledge on cross flows in BWR rod bundles is necessary for a solid prediction of the critical heat flux and for a proper description of neutron moderation and absorption by the coolant mixture. The aim of our research is to improve the current understanding in two-phase cross flows, using both experimental and numerical techniques. A 1,5 m high vertical scale model, consisting of two channels (2 x 3.9 cm) connected by a 3 mm high 2 cm wide slit has been constructed, through which water flows. Tracer and/or air bubbles of predefined size can be injected in one of the channels. Reynolds number with respect to the sub-channels has been varied between 300 and 14,000. Measurement of tracer and bubble concentration allowed the determination of the cross flow of both phases. The effects of changes in air and water superficial velocity and bubble size have been investigated. This has revealed very high cross-flow rates in the transitional regime (Re = 1500). Both at higher and lower Reynolds numbers, the cross-flow rate reduces with as much as 96%. Large bubbles also significantly reduce the cross-flow rates of both the continuous and the dispersed phase. The flow
More>>
Lexmond, Axel S;
Mudde, Rob F;
[1]
van der Hagen, Tim HJJ
[2]
- Prins Bernhardlaan 6 2628 BW Delft (Netherlands)
- Mekelweg 15 2629 JB Delft (Netherlands)
Citation Formats
Lexmond, Axel S, Mudde, Rob F, and van der Hagen, Tim HJJ.
Measurement of two-phase cross flow in a mock-up of interconnected rod bundle sub-channels.
France: N. p.,
2005.
Web.
Lexmond, Axel S, Mudde, Rob F, & van der Hagen, Tim HJJ.
Measurement of two-phase cross flow in a mock-up of interconnected rod bundle sub-channels.
France.
Lexmond, Axel S, Mudde, Rob F, and van der Hagen, Tim HJJ.
2005.
"Measurement of two-phase cross flow in a mock-up of interconnected rod bundle sub-channels."
France.
@misc{etde_20611129,
title = {Measurement of two-phase cross flow in a mock-up of interconnected rod bundle sub-channels}
author = {Lexmond, Axel S, Mudde, Rob F, and van der Hagen, Tim HJJ}
abstractNote = {Full text of publication follows: Knowledge on cross flows in BWR rod bundles is necessary for a solid prediction of the critical heat flux and for a proper description of neutron moderation and absorption by the coolant mixture. The aim of our research is to improve the current understanding in two-phase cross flows, using both experimental and numerical techniques. A 1,5 m high vertical scale model, consisting of two channels (2 x 3.9 cm) connected by a 3 mm high 2 cm wide slit has been constructed, through which water flows. Tracer and/or air bubbles of predefined size can be injected in one of the channels. Reynolds number with respect to the sub-channels has been varied between 300 and 14,000. Measurement of tracer and bubble concentration allowed the determination of the cross flow of both phases. The effects of changes in air and water superficial velocity and bubble size have been investigated. This has revealed very high cross-flow rates in the transitional regime (Re = 1500). Both at higher and lower Reynolds numbers, the cross-flow rate reduces with as much as 96%. Large bubbles also significantly reduce the cross-flow rates of both the continuous and the dispersed phase. The flow pattern has been studied using particle image velocimetry (PIV). Both the size of the vortex-like structures and the transverse fluid velocity depend on the Reynolds number. Large structures with high transverse velocity are only found in the transitional regime, explaining the outcome of the tracer experiments. Further work will be conducted and presented on velocity measurements at higher Reynolds numbers and of multi-phase flows as well as flows in curved slits. (authors)}
place = {France}
year = {2005}
month = {Jul}
}
title = {Measurement of two-phase cross flow in a mock-up of interconnected rod bundle sub-channels}
author = {Lexmond, Axel S, Mudde, Rob F, and van der Hagen, Tim HJJ}
abstractNote = {Full text of publication follows: Knowledge on cross flows in BWR rod bundles is necessary for a solid prediction of the critical heat flux and for a proper description of neutron moderation and absorption by the coolant mixture. The aim of our research is to improve the current understanding in two-phase cross flows, using both experimental and numerical techniques. A 1,5 m high vertical scale model, consisting of two channels (2 x 3.9 cm) connected by a 3 mm high 2 cm wide slit has been constructed, through which water flows. Tracer and/or air bubbles of predefined size can be injected in one of the channels. Reynolds number with respect to the sub-channels has been varied between 300 and 14,000. Measurement of tracer and bubble concentration allowed the determination of the cross flow of both phases. The effects of changes in air and water superficial velocity and bubble size have been investigated. This has revealed very high cross-flow rates in the transitional regime (Re = 1500). Both at higher and lower Reynolds numbers, the cross-flow rate reduces with as much as 96%. Large bubbles also significantly reduce the cross-flow rates of both the continuous and the dispersed phase. The flow pattern has been studied using particle image velocimetry (PIV). Both the size of the vortex-like structures and the transverse fluid velocity depend on the Reynolds number. Large structures with high transverse velocity are only found in the transitional regime, explaining the outcome of the tracer experiments. Further work will be conducted and presented on velocity measurements at higher Reynolds numbers and of multi-phase flows as well as flows in curved slits. (authors)}
place = {France}
year = {2005}
month = {Jul}
}