Lewis DMR commissions large-scale test facility

During loss-of-coolant accidents (LOCAs), operators may start accident management (AM) actions when the core exit temperature (CET) measured by thermocouples exceeds a certain value. However, a significant time delay and temperature discrepancy in the superheat detection were observed in several facilities. This work is focused on clarifying CET thermocouple responses versus peak cladding temperature (PCT) and studying if the same physical phenomena are reproduced in two TRACE5 models with different geometry (a large-scale test facility (LSTF) and a scaled-up LSTF) during a pressure vessel (PV) upper head small break LOCA (SBLOCA). Results obtained show that the delay between the core uncover and the CET excursion is reproduced in both cases.

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Underground large scale test facility for rocks

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts ◽

10.1016/0148-9062(83)91638-8 ◽

1983 ◽

Vol 20 (1) ◽

pp. A3

Author(s):

P.N. Sundaram

Keyword(s):

Large Scale ◽

Test Facility ◽

Scale Test

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Experimental Investigation of a Leading Edge Cooling System With Optimized Inclined Racetrack Holes

Volume 5A: Heat Transfer ◽

10.1115/gt2014-26219 ◽

2014 ◽

Cited By ~ 2

Author(s):

Carlo Carcasci ◽

Bruno Facchini ◽

Lorenzo Tarchi ◽

Nils Ohlendorf

Keyword(s):

Film Cooling ◽

Large Scale ◽

Cooling System ◽

Leading Edge ◽

Test Facility ◽

Cooling Flow ◽

Nusselt Numbers ◽

Nusselt Number Distribution ◽

Scale Test ◽

Film Cooling Holes

An experimental survey of a leading edge cooling scheme was performed to measure the Nusselt number distribution on a large scale test facility simulating the leading edge cavity of an high pressure turbine blade. Test section is composed by two adjacent cavities, a rectangular supply channel and the leading edge cavity. The cooling flow impinges on the concave leading edge internal walls, by means of an impingement array located between the two cavities, and it is extracted through showerhead and film cooling holes. The impingement geometry is composed by a double array of circular or shaped holes. The aim of the present study is to investigate the heat transfer performance of two optimized impingement schemes in comparison with a standard one with circular and orthogonal holes. Both the optimized arrays have inclined racetrack shaped holes and one of them has also a converging shape. Measurements were performed by means of a transient technique using narrow band Thermo-chromic Liquid Crystals (TLC). Jet Reynolds number was varied in order to cover the typical engine conditions of these cooling systems (Rej = 15000–45000). Results are reported in terms of detailed 2D maps, radial and tangential averaged Nusselt numbers.

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Sampling Based Uncertainty Analysis of 10% Hot Leg Break LOCA in LSTF

ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting: Volume 1, Symposia – Parts A, B, and C ◽

10.1115/fedsm-icnmm2010-31288 ◽

2010 ◽

Author(s):

Samiran Sengupta ◽

S. K. Dubey ◽

R. S. Rao ◽

S. K. Gupta ◽

V. K. Raina

Keyword(s):

Sensitivity Analysis ◽

Uncertainty Analysis ◽

Large Scale ◽

Latin Hypercube Sampling ◽

Test Facility ◽

Accident Analysis ◽

Design Matrix ◽

Best Estimate ◽

Scale Test ◽

Screening Sensitivity

This paper describes the uncertainty analysis carried out for 10% Hot leg break LOCA of Large Scale Test Facility as a part of IAEA Coordinated Research Project on “Evaluation of Uncertainty in Best Estimate Accident Analysis”. The best estimate code used for this analysis is RELAP5/MOD3.2. Initially the nodalisation of the test facility for carrying out the analysis is qualified for both steady state and transient level by systematically applying the procedures lead by Uncertainty Methodology based on Accuracy Extrapolation developed at University of Pisa. Subsequently the uncertainty analysis is carried out using sampling based Monte Carlo approach, which involves the generation and extrapolation of a mapping from uncertain inputs to the uncertain analysis results. The major steps followed in this methodology mainly includes screening sensitivity analysis for input parameters, design matrix generation using Latin Hypercube Sampling, representation of uncertainty analysis results based on best estimate thermal hydraulic code runs and importance /sensitivity analysis using regression analysis. The steps followed have been described in details in this paper.

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