SPECTRA, thermal hydraulic design tool for power plants (nuclear and conventional) . A product of NRG (An ECN-KEMA company)

Product: SPECTRA, thermal hydraulic design tool for power plants (nuclear and conventional)

Group: Plant Performance Technology (PPT)

SPECTRA, thermal hydraulic design tool for power plants (nuclear and conventional)

SPECTRA (Sophisticated Plant Evalua-tion Code for Thermal--hydraulic Response Assessment) is a computer program designed for thermal-hydraulic design analyses of nuclear or conventional power plants. It can be used for simulating steady state performance as well as plant performance with transient conditions (operational transients and accidents). NRG initiated the development of SPECTRA in 1994 and it has now been established as a mature tool. The development went in parallel with a major verification and validation effort (benchmarks, integral test comparisons etc.) which demonstrated that SPECTRA is a reliable, accurate and robust code.

SPECTRA is capable of analysing the whole of a nuclear power plant, including the reactor with point-kinetics energy generation, primary system, various control and safety systems, containment and reactor building. In contrast to traditional codes for nuclear plant thermal-hydraulic analysis, which are basically steam-water codes, SPECTRA has been built to allow the presence of a mixture of multiple gases/fluids and contains a built-in library of fluid properties (water, steam, non-condensable gases such as H2, He, N2, O2, CO2) covering a wide temperature range (270 K to 2070 K) and pressure range (virtually from 0 Pa to 107 Pa). Other gases/fluids may be incorporated when needed. In addition from the general heat & mass transfer physics models for continuous fluids SPECTRA also covers specific physical phenomena associated with multiphase/multifluid media (see illustration) and empirically takes stratification into account. When SPECTRA application is envisaged for thermal power plants, energy sources and mass sources (burning products) may be used as user defined input functions.

Over the past years SPECTRA was already applied extensively with the new reactor design SWR-1000 (Siemens/Framatome-ANP) and this led to its selection as the licensing code for LOCA-/containment analyses. Other nuclear applications also included analyses of the Borssele nuclear power plant with accident scenarios involving hydrogen distribution. During 2001 SPECTRA further was adopted by PBMR(Pty) as the tool for "Verification & Validation" in support of the system design analyses for license submittal of the new PBMR-reactor. Work also continues on the application of SPECTRA for simulating the sytem performance of a coal-fired power plant. Although, at present SPECTRA is only used by NRG it is anticipated that SPECTRA will be available to other interested users in the near future through commercial licensing.

Possible phenomena within each cell of the multi-phase thermal-hydraulic SPECTRA-code

Contactperson:
Dr. V.A. Wichers
NRG, PO Box 25, 1755 ZG Petten, Netherlands
tel: +31-224 564656, fax: +31-224 568490, e-mail: wichers@nrg.eu

NRG, PO Box 25, NL-1755 ZG Petten, Netherlands, Tel +31-224564950, Fax +31-224568912
Information: info@nrg.eu
Update 18 February 2004