Transcript COG-University Interaction

Interaction with Universities
and
CATHENA Water Properties
by
Laurence Leung & Thomas Beuthe
Presented at the CNC-IAPWS meeting
Friday, May 23 2003
COG Offices, Toronto
COG-University Interaction
Laurence Leung
Fuel Channel Thermalhydraulics Branch
AECL
Pg 2
COG-University Interaction
 Arrangement
 Via COG project contractors (e.g., AECL)
 Fundamental research topics of interest to COG
 Thermalhydraulics (simple tubes and annuli)
 Fluid properties (light water, heavy water, non-aqueous fluids)
 Funding options
 Direct support (projects related to the nuclear industry only)
 Joint program with NSERC (projects related to nuclear and
other industries)
Pg 3
COG-University Interaction
 Benefits
 Cost reduction (support PDFs and grad. students only,
university covers professor’s time)
 Training of potential employees for the industry (most PDFs
and grad students have been employed by various
organizations within the industry)
 International cooperation (much easier via universities, which
are non-commercialized organizations, e.g., data exchange,
staff attachment)
 Publicity (COG support is acknowledged in posters around
the experimental facilities during university open house and
tours of visitors/students from other universities and
organizations)
Pg 4
Fluid Properties Development
 Thermalhydraulics calculations
 light water and heavy water
 Freons
 Reactor safety codes and PC software applications
 Distribution to other parties
 QA issue
 License issue
 University cooperation to develop specific properties
routines using available information from open
literature
Pg 5
CATHENA
Thomas Beuthe
Containment and Thermalhydraulics Branch
AECL
Pg 6
CATHENA
 CATHENA is a Thermalhydraulic Network Analysis
code.
 Developed by AECL primarily for analysis of CANDU
reactors.
 Uses a transient, 1-D, non-equilibrium 2-fluid
representation of two-phase flow in piping networks.
 Thermalhydraulic model solves 6 partial differential
equations for conservation of mass, momentum and
energy for each phase.
 Utilizes a 1st order, finite difference, semi-implicit, onestep method, not limited by material Courant number.
Pg 7
HLWP
 Heavy and Light Water Property routines
 Given P,h (CATHENA dependent variables) HLWP provides
 Thermodynamic values: hl, hv ρl, ρv, T (and their derivatives w.r.t. to
P at saturation), and ρl, ρv, Tl, Tv, Cpl, Cpv, ∂ρl/∂hl│P, ∂ρv/∂hv│P,
∂ρl/∂Pl│h, ∂ρv/∂Pv│h
 Transport properties: sonic velocity, dynamic viscosity, thermal
conductivity, surface tension.
 Noncondensable Gas Properties, ideal gas property data for Air,
H2, N2, Ar, He and CO2
 Originally developed for CATHENA
 Currently also used by other AECL codes (ASSERT,
TUBRUPT)
Pg 8
HLWP
 Current range of applicability for water:
 P: 611.73 Pa – 22.046 MPa
 h: 0 kJ/kg – 1770 kJ/kg (liquid)
2190 kJ/kg – 7400 kJ/kg (vapour)
(above 7400 kJ/kg ideal gas law assumed,
upper limit 12,000 kJ/kg or about 4000 C)
 Applicable in the liquid, vapour and metastable regions.
Pg 9
HLWP
 Routines use a 1-D cubic Hermite polynomial fit for
thermodynamic saturation values, and a bi-quintic
Hermite polynomial fit for single-phase liquid and
vapour states.
 Generating function used to produce fitting data was
the 1984 NBS/NRC (IAPS-84) by Haar, Gallagher and Kell
(H2O), and Hill’s 1981 formulation for D2O.
Pg 10
HLWP
 Recently, and effort was made to bring together all
parties interested in HLWP within AECL to specify
requirements for an updated HLWP library.
 Currently, a project is underway to:
 Provide a useful user-interface to HLWP
 Update HLWP using the latest available data
 Increase accuracy of fit and extend range (metastable,
supercritical, dissociation?)
Pg 11
Hermite fit
 Internally, HLWP is fit using the values of entropy and
its derivatives: s, sh, sp, shp, spp, shh, spph, shhp, spphh,
where sh= ∂s/∂h
 These derivates form a basis for the Hermite
polynomial fit, but can also be used to derive the
needed thermodynamic values as follows:
Pg 12
Hermite fit
T = 1/sh
ρ = -sh/sp
Cp = -sh2/shh
∂ρ/∂h│P = (shpsh-shhsp)/sp2
∂ρ/∂P│h = (sppsh-shpsp)sp2
Pg 13
Current Work
 Re-fitting HLWP to latest IAPWS-95 standard. In
general, current standard is smoother, more consistent,
and offers ability to quote absolute accuracy.
 Some interesting issues identified:
 “Glitch” in the saturation value of dynamic viscosity
 No user support for metastable regions (wild west!)
Pg 14
Dynamic viscosity at saturation for liquid
5.3e-005
5.2e-005
5.1e-005
5e-005
4.9e-005
4.8e-005
4.7e-005
4.6e-005
2.1e+007
2.12e+007
2.14e+007
2.16e+007
2.18e+007
2.2e+007
Pressure (Pa)
Pg 15
Dynamic viscosity at saturation for vapour
3.8e-005
3.7e-005
3.6e-005
3.5e-005
3.4e-005
3.3e-005
3.2e-005
3.1e-005
3e-005
2.9e-005
2.1e+007
2.12e+007
2.14e+007
2.16e+007
2.18e+007
2.2e+007
Pressure (Pa)
Pg 16
Overview
3e+006
Vapour Saturation
10MPa
limit
“5%” limit
2.5e+006
Haar practical limit
2e+006
IAPWS-95 Spinodal
IAPWS-95 Ideal
Gas Spinodal
1.5e+006
Haar Practical Limit
Bochum Practical Limit
1e+006
500000
0
100
Liquid Saturation
1000
10000
100000
Enthalpy [J/kg]
1e+006
1e+007
1e+008
Pg 17
Additional considerations





“5%” metasable vapour line (small zone!)
10MPa transition line
Ideal gas to regular property transition
Subcritial to supercritical transition
Metastable zones: spinodals represent the absolute
limit, but what is the “reasonable” limit? (No guidance!)
 High temperature (dissociation!)
Pg 18
Looking Ahead
 Need update to D2O properties?
 release rates of noncondensable gases from solution
(e.g. Air, N2, H2)
 decomposition rates for hydrazine and the production
of noncondensable gases
 absorption of noncondensable gases by water
Pg 19
Conclusions
 Good cooperation with universities on water
properties, leaveraging the availaible resources to their
best potential
 Active work is proceeding to update water properties in
the leading AECL property routines.
 Issues identified in property generation routines:
 Operation of IAPWS-95 implementations in metastable
regions
 Stability of Bochum routines
 Need for smooth data (e.g. dynamic viscosity at saturation)
Pg 20