Valeriy Kolesnik Tel CFD-consultant Russia Intellectual and other property rights to the information contained in this document are held by PlasmaVenture Ltd. with all rights reserved © 2003 OPTIMIZATION OF POROUS ACCEPTING STEAM HOLES LEAF (ASHL) HORIZONTAL STEAMGENERATOR SG Ref: SAFETY ASSURANCE OF NPP WITH WWER The 4-th Scientific & Technical Conference May 23-26, 2005 Podolsk, RUSSIA MOSCOW APRIL, 2005 FSUE OKB Gidropress (Podolsk), Russia Ref:

Horizontal Steam Generator (SG-1500) Hot Collector (HC) The Purpose Researches: Optimization of POROUS ACCEPTING STEAM HOLES LEAF IN THE TOP PART HC/SG1500 Cold Collector (CC)HC CC FSUE OKB Gidropress (Podolsk), Russia

3D MODEL SG-1500 FSUE OKB Gidropress (Podolsk), Russia Out Steam Cold Water Inlet HOT COLLECTOR TRUMPET BUNCH SG-1500 Out Steam Inlet HOT COLLECTOR

3D MODEL SG (GAMBIT v.2.1) Gambit

LAB. MODEL TOP PART SG-1500

Boundary conditions Holes Leaf(ASHL): porosity (2.5÷10.0) % Vertical Wall: porosity 25.0% Holes in ASHL : model of a porosity code Fluent Collectors and pipe cold water : are not considered The area of mirror of evaporation: 52.3m 2 Velocity above a mirror of evaporation: (0.28÷0.35) m/s Through passage section of 2 branch pipes: 0.36 m 2 Pressure upon an output of Branch pipe SG-1500: 7.34 MPa Hydraulic resist. Sg-1500 on a steam path SG-1500: 0.10МPa Factor of non-uniformity of the charge Steam above ASHL:.1.0 Turbulence: turbulent (model - code FLUENT) Coolant: ideal gas with properties steam on a line of saturation Geometry 2D & 3D. In this presentation are presented 2D calculation. On the right border condition of symmetry are taken. On the bottom border of a conditions inlet velocity. On the top border conditions on pressure. On other borders of a conditions WALL. Calculation Mesh hybrid (rectangular, passing in curvilinear quadrangular or triangular The minimal size of a cell of 5mm. Maximal size: 10 sm. Quantity of cells : Hybrids mesh has fast convergence of the decision (after 100 iterations). Criterion convergence : The tool : CFD code FLUENT v Solverь : Segregated Method : Ipmlicit Average time of one 2D calculation has made 15 minutes

Gambit 3D MESH ( GAMBIT v.2.1)

2D MESH ( GAMBIT v.2.1) Fragment.

2D RESULTS. VARIANT 1. Distribution of Streamlines In longitudinal section SG-1500 without ASHL.. Structure longitudinal components velocity U stream steam in SG-1500 without ASHL on distance 610 mm from mirror.

2D RESULTS. VARIANT 2. Distribution of streamlines in longitudinal section SG ASHL from a constant on porosity equal 0.055, lateral walls continuous. Structure longitudinal components velocity of a stream steam U on length SG-1500 on distance of 610 mm from ASHL. ASHL from a constant on length porosity equal 0.055, lateral walls continuous.

2D RESULTS. VARIANT 3. A structure longitudinal components VELOCITY of a stream steam U on length SG-1500 On distance of 610 mm from mirror. ASHL from a variable on length porosity. Average size porosity equal 0.055, lateral wall Distribution of sreamlines in longitudinal section SG ASHL from a variable on length porosity. Average size of porosity equal 0.055, lateral walls 0.25.

2D RESULTS. POROSITY. RECOMENDATIONS.

CONCLUSION: Optimization of a structure of punching ASHL was spent with the punched lateral walls. And the degree of porosity lateral walls was required to greater, than the bottom surface. The calculations structure of punching ASHL represented to presentations was the seventh iteration. Streamlines are noticeably inclined in two places SG at end faces and under a target branch pipe. Structures of speeds U=f(x) have shown, that the punched lateral wall leads to appreciable decrease in values longitudinal velocity and in face areas SG In the chosen section (z 1/2 Нн) steam volume the maximal value of longitudinal speed under Influence ASHL has decreased approximately in 5 times. The location of the maximal speed is approximately under a branch pipe. Here longitudinal speed has remained in 2.8 times above average speed of an output. Steam from a surface of evaporation. Condition U /Uo <1 was provided for 60% lengths SG-1500 in the chosen section. Thus, influence of target branch pipes to weaken up to comprehensible values it was not possible. Carrying out of the further calculations is necessary. But from these calculations follows, that easing of influence two branch pipes on occurrence of significant longitudinal speeds probably, but there is no algorithm approach the purpose. The last concerns both settlement, and to experimental researches. The degree of punching of a lateral wall is received equal 0,25 at average on bottom surface ASHL The minimal values of porosity (0.04) correspond to an arrangement of target branch pipes, maximal (0.1) - the middle of length ASHL

REFERENCES: 1.N.G.RASSOHIN STEAMGENERATOR INSTALLATIONS NUCLEAR POWER STATIONS. M.ATOMIZDAT,1980. PAGE THE TECHNICAL PROJECT ON WORK ON CALCULATE & EXPERIMENTAL SUBSTANTIATION OF A DESIGN AND OPTIMIZATION OF A FLOWING PART OF A COLLECTOR SG-1500, CONTRACT 3103, THE DRAWING OF A DISTRIBUTING COLECTOR OF STEAMGENERATORS SG BO,OKB GIDROPRESS, STEAMGENERATOR. AN EXPLANATORY NOTE 448-PR-025,OKB GIDROPRESS, 2001.