MPBR Modularity Plan • Road- Truck / Standard-Rail Transportable – 8 x 10 x 60 ft. 100,000 kg Limits • Bolt-together Assembly – Minimum labor / time on site required – Minimum assembly tools – Goal: Zero Welding • Minimum Site Preparation – BOP Facilities designed as “Plug-and-Play” Modules – Single Level Foundation – System Enclosure integrated into modules • ASME Code compliant – Thermal expansion limitations – Code material limitations
Space Frame Technology f or Shipment and Assembly
Current MI T/ I NEEL Design Layout Reactor Vessel Intermediate Heat Exchangers High Pressure Turbine and Compressor Turbo-generator Low Pressure Turbine and Compressor Precooler Recuperators
Reactor Vessel Present Layout IHX Vessel High Pressure Turbine Low Pressure Turbine Compressor (4) Power Turbine Recuperator Vessel
Plant With Space Frames
For 1150 MW Electric Power Station Ten-Unit MPBR Plant Layout (Top View) (distances in meters) 0 20 40 60 80 100 120 140 160 0 Admin 20 Equip Equip 9 7 5 3 1 Training Access Access Hatch Hatch 40 Control 60 Equip 8 6 Access 4 2 Bldg. 10 Hatch 80 Maintenance Parts / Tools 100 Turbomachinery Turbine Hall Boundary Primary island with reactor and IHX
AP1000 Footprint Vs. MPBR-1GW ~400 ft. ~200 ft.
Intermediate Heat Exchanger Design Prof. R. Ballinger, P. Stahle Jim Kesseli - Brayton Energy
Heat Exchanger Design • Two Concepts Identified Compact Plate-Fin (NREC) PCHE Design (Heatric) • Base Designs Established • Model Developed for System Analysis • Limitations Identified
Compact Plate-Fin Old Design (NREC)
Printed Circuit Design (Heatric)
IHX Primary Conditions • Inlet 900 o C – Temperature – Pressure 7.73 Mpa • Outlet 509 o C – Temperature – Pressure 7.49 Mpa • Flow ~130 Kg/s
IHX Secondary Conditions • Inlet 488 o C – Temperature – Pressure 7.99 Mpa • Outlet 879 o C – Temperature – Pressure 7.83 Mpa • Flow ~130 Kg/s
IHX Modular Assembly Isometric View • Six units per assy. • Interconnection piping between units • Pipe loops relieve expansion stress • Small units for ease of fabrication and maintenance.
IHX Design Data (Concepts-NREC) Effectiveness (%) 90 92.5 95 Hot Side Pres. Loss (%) 1.60 1.68 1.77 Cold Side Pres. Loss (%) 2.00 2.00 2.00 Number of Modules 6 6 6 Module Width (mm) 600 600 600 Module Length (mm) 885 1013 1255 Module Height (mm) 2773 3014 3454 Est. Wt. PC Config. (kg) 38,854 50,669 76,233 Est. Wt. PF Config. (kg) 10,335 13,478 20,278 Cost (M$) 4.53 5.91 8.88
Heat Exchanger Core Modules • Plate Fin 92% Eff • Printed Circuit 92% – Wt 30,000 lb. – Wt 111,700 lb. – Ht 118” – Ht Same as PF – Wd 24” – Wd Same as PF – Dp 40” – Dp Same as PF • 18 Req’d for IHX • 18 Req’d for IHX
IHX Unit Pressure Vessel • Dia. 90.5” • Thk. 2” • Ht. 240” • Wt. 90,000 lb – (inc. Plate Fin xch.)
Cooled Internal Volume 288 o C • Temp. • Press. ~8 Mpa • ASME Sec III Bndry • Piping grouped by temperature • Internal legs for flexibility
Primary Internals • (3) Plate Fin Core Modules • Core Modules Suspended to accommodate expansion
Plate Fin Grouping • Primary Inlet • Primary Outlet • Secondary Inlet • Secondary Outlet
Future Plans • Join with industrial partner(s) to develop highest temperature IHX (900-950 C) possible using current material knowledge for Hydrogen demonstration plant. • Identify key design issues for higher temperatures including transients. • Work on materials challenges for higher temperature operation. • Modular approach allows for testing.
Proposed Test Program f or Advanced High Temperat ure Plat e Fin HX (800 - 1000 C) Figure 6 Unit Cell Pressure Fatigue Test at Elevated Temperature. This test conducts numerous pressure cycles on three cells at elevated temperature (800 and 1000 C). At each MI T/ Brayt on Energy selected pressure, the cycling will continue to failure (ie gas leakage is out of spec). The test will be performed at three to five pressures of increasing magnitude. The data will be formulated into an endurance plot. The results will be used to calibrate and validate the analytical models. The MIT high- 1. Unit Cell Pressure Fatigue Test temperature furnace is capable of heating three or more cells to 1000 C. Figure 7 Unit cell Creep Test and Elevated Temperatures. This test will use a modified version of the rig MIT high temp furnace. The tests are performed at steady pressure and temperature conditions. An empirical 2. Unit cell Creep Test Larsen-Miller map of the cell is created by operating the cell to failure at two elevated temperatures, 800 and 1000 C. The pressures imposed on the cell will be selected to induce failure at intervals ranging from one hour to 1000 hours. Failure is indicated by the cells inability to maintain the leak specification. After 3. Thermal Strain Measurement completing the mapping, three cells will be subjected to the design pressure and temperature and left to operate indefinitely. Inspection will be made at for model Validation. regular intervals. Figure 8 Thermal Strain Measurement for model Validation. This test rig will heat a sub-core (5 or more cells) to an elevated temperature, but not so high as to compromise the accuracy of piezoresistive strain gauges. Transient temperature and strain measurements will be recorded while flowing very cold gas generated from a liquid nitrogen bath on one side and combustion products from a commercial burner on the other side. Proof of manufacturability, demonstration of mechanical integrity, and validation of analytical life prediction models are critical steps towards the qualification of the proposed high temperature heat exchanger. This program will address a these three steps by fabricating and instrument roughly 30 IHX cells for a series of rigorous endurance tests and characterizing.
Hydrogen Mission Modularity Flexibility Hydrogen Plant A Hydrogen Plant B Secondary IHX - Helium to Molten Salt? May use one or more IHX’s from base electric plant for H 2
An Integrated Fuel Performance Model for Modular Pebble Bed Reactor Jing Wang Professor R. G. Ballinger
Fuel Performance Model • Detailed modeling of fuel kernel • Microsphere • Monte Carlo Sampling of Properties • Use of Real Reactor Power Histories • Fracture Mechanics Based • Considers Creep, stress, strains, fission product gases, irradiation and temperature dependent properties.
Fuel Performance The Key Safety System • Develop Fuel Performance Model • Develop an optimized design for reliability • Work with manufacturer to optimize • Make fuel and test
Integrated Fuel Performance Model Power Distribution in the Reactor Core MC Outer Loop 1,000,000 times Sample a pebble/fuel particle MC inner loop 10 times Randomly re-circulate the pebble t=t+ ∆ t Monte Carlo outer loop: Get power density, neutron flux Samples fuel particle statistical characteristics T distribution in the Accumulate fast FG release (Kr,Xe) pebble and TRISO neutron fluence PyC swelling MC inner loop: Mechanical model Implements refueling scheme in reactor core Failure model Mechanical Chemical Stresses FP distribution Strength Pd & Ag Y Failed N Y In reactor core N
Simulation of Refueling - cont’d 1.6E+07 1.4E+07 1.2E+07 Power density (W/m^3) 1.0E+07 8.0E+06 6.0E+06 4.0E+06 2.0E+06 0.0E+00 0 100 200 300 400 500 600 700 800 Irradiation time (days) A typical power history of a pebble in MPBR core
Simulations Kernel Buffer IPyC SiC OPyC Kernel Fuel Type Density Diameter Thickness Thickness Thickness Thickness (g/cm 3 ) ( µ m) ( µ m) ( µ m) ( µ m) ( µ m) UCO 10.70 195 100 53 35 43 NPR UO 2 10.96 600 60 30 25 45 HTTR NPR — New Production Reactor (USA) HTTR — High Temperature Test Reactor (Japan)
Circumferential Stresses in NPR & HTTR Type Fuel 400 200 0 IPyC_NPR Stress (MPa) SiC_NPR -200 OPyC_NPR IPyC_HTTR SiC_HTTR -400 OPyC_HTTR -600 -800 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Fast Neutron Fluence (10^21nvt)
NPR & HTTR Type Fuel Reliability in MPBR Environments IPyC OPyC Particle Cases SiC Failure Failure Failure Failure Sampled Probability Probability Probability Probability NPR type 1,000,000 27.79% 17.07% 13.30% 13.30% fuel HTTR type 1,000,000 5.660% 16.22% 0.1017% 0.1017% fuel All particle failures observed were induced by IPyC cracking
Fuel Design Parameters Parameter Design Value Uncertainty As-Fabricated Uncertainty Value Uranium Enrichment (%) 96 0.1 96 0.1 Kernel Density (gm/cm 3 ) 10.4 0.01 10.4 0.01 Kernel Theoretical Density (gm/cm 3 ) 10.95 - 10.95 - Kernel Diameter ( µ m) 500 20 497 14.1 Buffer Density (g/cm 3 ) 1.05 0.05 1.05 0.05 Buffer Theoretical Density (g/cm 3 ) 2.25 - 2.25 - Buffer Thickness ( µ m) 90 18 94 10.3 IPyC Initial BAF 1.05788 0.00543 1.05788 0.00543 IPyC Density (g/cm 3 ) 1.9 - 1.9 - IPyC Characteristic Strength (MPa.m 3 /Modulus) 24 - 24 - IPyC Weibull Modulus 9.5 - 9.5 - IPyC Thickness ( µ m) 40 10 41 4 OPyC Initial BAF 1.05788 0.00543 1.05788 0.00543 OPyC Density (g/cm 3 ) 1.9 - 1.9 - OPyC Characteristic Strength (MPa.m 3 /Modulus) 24 - 24 - OPyC Weibull Modulus 9.5 - 9.5 - OPyC Thickness ( µ m) 40 10 40 2.2 SiC Thickness ( µ m) 35 4 36 1.7 SiC Characteristic Strength (MPa.m 3 /Modulus) 9 - 9 - SiC Fracture Toughness (MPa. µ m 1/2 ) 3300 530.7 3300 530.7 SiC Weibull Modulus 6 - 6 -
Fuel Performance Model Development Path Transient & Steady State Accident Initial Steady State Model • Initial Probabilistic Fracture Mechanics Model • Simple Chemistry Model Current Development Status Advanced Steady State Model • Advanced Fracture Mechanics Model Initial Transient & • Ag Migration & Release Model Accident Model Complete Steady State Model • Detailed Chemical Model Complete Transient & • Detailed Layer Degradation Model Accident Model
Conclusions • A fuel performance model has been developed which can simulate fuel behavior in Pebble Bed Reactor cores • Monte Carlo simulations can be performed to account for particle-to-particle variability in fabrication parameters as well as variability in fueling during operation • Results have been compared with other models and with actual fuel performance . • Model can be used to optimize fuel particle design
Silver Transport in Silicon Carbide for High-Temperature Gas Reactors Heather J. MacLean Professor Ronald Ballinger
Barrier Integrity • Silver Diffusion observed in tests @ temps • Experiments Proceeding with Clear Objective - Understand phenomenon • Focus on Grain SiC Structure Effect
Silver Ion Implantation SiC masks on sample frame Light transmission through SiC mask and sample • 161 MeV silver beam, peak at 13 µm • 93 MeV silver beam, peak at 9 µm implanted ~10 17 ions = ~2 atomic % silver • • measure silver concentration profiles • examine SiC damage
Ion Implantation Silver Depth Profile Sample 2b Predicted Profile 2.0 1.8 Ag as implanted 2a Ag after 210 hr heat 1.6 2b Atomic Concentration (%) 1.4 1.2 1.0 0.8 No silver movement 0.6 No silver movement after 210 hr at 1500° °C C after 210 hr at 1500 0.4 0.2 0.0 0 2 4 6 8 10 12 14 16 18 Depth ( µ m)
Spherical Diffusion Couple Experiments CVD SiC coating RESULTS graphite or SiC shell • No silver in SiC depth profiles • Mass loss after heating silver • Leak rates increased after heating Diffusion couple (cross-section) optical microscopy from top of graphite-SiC diffusion couple
Calculated Silver Diffusion (from release) low silver concentration 1600 o C 1200 o C 1000 o C ~2 ppm 1.E-10 Release coefficients calculated from silver release 1.E-11 (current experiments) R e le a s e c o e ffic ie n ts c a lc u la te d fr o m s ilv e r r e le a s e 100 ppm boundary condition ( c u r r e n t e x p e r im e n ts ) 2 ppm boundary condition 1.E-12 high silver concentration Mass Transfer Coefficients (m 2 /s) (unit activity) Release Coefficient (m 2 /s) 1.E-13 1.E-14 1.E-15 Selected Literature Data 1.E-16 D calculated from silver release (literature) 1.E-17 Amian & Stover calculated fit 1.E-18 Nabielek et al. ion implantation limit 1.E-19 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 10 4 /T (K)
Silver Mass Loss SiC-1 SiC-2 SiC-3 graphite shell, standard SiC coating graphite shell, modified SiC coating SiC shell, standard SiC coating 1.2 1.2 1.2 1 1 1 Fractional Silver Loss Fractional Silver Loss Fractional Silver Loss 0.8 0.8 0.8 0.6 0.6 0.6 0.4 0.4 0.4 0.2 0.2 0.2 0 0 0 1000 1200 1400 1600 1800 1000 1200 1400 1600 1800 1000 1200 1400 1600 1800 Heating Temperature ( o C) Heating Temperature ( o C) Heating Temperature ( o C) (normalized to seam area)
Possible Nano-Cracking • Nanometer-sized features (cracks) observed in experimental SiC coating in AFM (atomic force microscopy) • Mechanical pathway • Origin not yet known • Stresses from differential thermal expansion between individual SiC grains may cause nano- scale cracks • May be aggravated by thermal cycling • Consistent with fuel performance discussions at ORNL
Conclusions • Silver does not diffuse through intact, fine-grained SiC – no change in silver concentration profiles – no silver movement despite increased grain boundary area • Vapor migration governs silver release from CVD SiC coatings – mass release observed, but silver profiles not found – increased leak rates indicate mechanical cracks • Transport model will compare proposed mechanisms with literature data • Continued SiC development needs to focus on identifying and eliminating crack path
Core Physics • Basic tool Very Special Old Programs (VSOP) • Developing MNCP Modeling Process • Tested Against HTR-10 Benchmark • Tested Against ASTRA Tests with South African Fuel and Annular Core
Modeling Considerations Packing of Spheres � Spheres dropped into a cylinder pack randomly � Packing fraction ~ 0.61 � Repeated-geometry feature in MCNP4B requires use of Random Close Packed a regular lattice � SC, BCC, FCC or HCP? � BCC/BCT works well for loose sphere packing Body Centered Cubic MIT Nuclear Engineering Departm ent 5
HTR-10 MCNP4B Model Core TRISO fuel particle Reactor Fuel sphere Core lattice MIT Nuclear Engineering Departm ent 12
MCNP4B/VSOP Model Output Power Density in PBMR Equilibrium Core Control Rods 1/4 Inserted (z = 201.25 cm) 8 7 Power density in annular 6 core regions 5 MW/m 3 4 7.00E+00-8.00E+00 3 6.00E+00-7.00E+00 2 5.00E+00-6.00E+00 1 top 4.00E+00-5.00E+00 0 3.00E+00-4.00E+00 Top of 0 core 161 2.00E+00-3.00E+00 242 402 175 1.00E+00-2.00E+00 483 134 Axial Position (cm) 644 Radial 0.00E+00-1.00E+00 108 725 0 Position (cm) MIT Nuclear Engineering Departm ent 25
ASTRA Critical Experiments Central Mixing zone A � Kurchatov Institute, Moscow h l Internal Side � Mockup of PBMR annular core reflector reflector Experimental channels 15 ZII З ZRTA1 Core Inner reflector : graphite spheres (M) 14 E3 10.5 cm ID 13 E2 12 72.5 cm OD SR8 CR2 SR4 PIR E4 11 10 SPU3 ZII1 SR2 CR3 Mixed zone: 50/47.5/2.5 (M/F/A) 9 E1 SR5 105.5 cm OD 8 CR1 MR1 ZII2 7 ZRTA4 Fuel zone: 95/5 (F/A) SPU1 6 SR1 SR6 ZRTA2 181 cm OD (equiv.) 5 CR4 4 PIR SR3 CR5 SR7 Core height: 268.9 cm 3 E6 ZPT2 2 � packing fraction = 0.64 ZII1 1 SPU2 E5 ZRTA3 B � 2.44 g U/FS, 21% U235, 0.1 g B/AS a b c d e f g h i j k l m n o CR - Control � 5 CRs, 8 SRs, 1 MR MR1 - Manual control d SR - Safety d � CR = 15 s/s tubes with B4C powder E1-E6 - Experimental chambers d 1-9 - Experimental channels for h l PIR,ZPT,ZII,ZRTA - Ionization chambers and neutron d t t � 6 in-core experimental tubes t Neutron source channel MIT Nuclear Engineering Departm ent 13
ASTRA Conclusions • Criticality Predictions fairly close ( keff = . 99977) • Rod Worth Predictions off 10% • Analysis Raises Issues of Coupling of Core
HTR-10 ( Beijing ) 10 MW Pebble Bed Reactor: � Graphite reflector � Core: R c = 90 cm, H ≤ 197 cm � TRISO fuel with 5 g U/Fuel Sphere � 17% U235 � F/M sphere ratio = 57:43, modeled by reducing moderator sphere size � Initial criticality December 2000 MCNP4B Results K-eff 1.00081± 0.00086 Critical Height 128.5 cm Calculated Loading 16,830 Actual Loading 16,890 MIT Nuclear Engineering Department 9
Safety Tieliang Zhai Prof. Hee Cheon No (Korea) Professor Andrew Kadak
Safety Issues • Loss of Coolant Accident • Air Ingress • Reactor Cavity Heat Removal
Safety • LOCA Analysis Complete - No Meltdown • Air Ingress to study fundamental processes and benchmark Computational Fluid Dynamics Codes - Conservative analysis show no “flame” - Address Chimney effect - Address Safety of Fuel < 1600 C - Use Fluent for detailed modeling of RV
Massachusetts Institute of Technology Department of Nuclear Engineering Advanced Reactor Technology Pebble Bed Project MPBR-5
Temperat ure Prof ile Fig-10: The Temperature Profile in the 73rd Day 1600 1400 1200 Concrete Wall 1000 Temperature (C) 800 Core Reflector Cavity Soil 600 Vessel 400 200 0 0 1 2 3 4 5 6 7 8 9 10 11 Distance to the Central Line
The Prediction of the Air Velocity (By Dr. H. C. No) Hot-Point Fig-14: Trends of maximum temperature for Temperature of the 0, 2, 4, 6 m/s of air velocity in the air gap region core(0m/s) Hot-Point 1800 Temperature of the Vessel (0m/s) Hot-Point 1600 Temperature of the Concrete Wall (0m/s) Hot-Point 1400 Temperature of the Core (2m/s) Hot-Point 1200 Temperature of the Temperature (C) Vessel (2m/s) Hot-Point 1000 Temperature of the Concrete Wall (2m/s) 800 Hot-Point Temperature of the Core (6m/s) 600 Hot-Point Temperature of the Vessel (6m/s) 400 Hot-Point Temperature of the Concrete Wall (6m/s) 200 Limiting Temperature for the Vessel 0 Limiting Temperature 0 30 60 90 120 150 180 210 for the Containment Time (hr)
Air Ingress Air/COx out • Most severe accidents among PBMR’s Vary Choke Flow conceivable accidents with a low occurrence frequency. • Challenges: Complex Bottom Reflector geometry, Natural Convection, Air In Diffusion, Chemical Reactions
Air Ingress Velocity f(temperature) Fig-2: Air Inlet Velocity Vs. the Average Temp. of the Gases 0.09 0.08 0.07 Air Inlet Velocity (m/s) 0.06 0.05 0.04 0.03 0.02 0.01 0 0 400 800 1200 1600 2000 2400 2800 3200 the Average Temp. of the Gases (C)
Preliminary Conclusions Air Ingress For an open cylinder of pebbles: • Due to the very high resistance through the pebble bed, the inlet air velocity will not exceed 0.08 m/s. • The negative feedback: the Air inlet velocity is not always increase when the core is heated up. It reaches its peak value at 300 ° C. • Preliminary combined chemical and chimney effect analysis completed - peak temperatures about 1670 C.
Simplified HEATING7 Open Cylinder Analysis Peak Temperature Figure 3: The peak temperature 1700 1600 1500 1400 Temperature (C) 1300 1200 1100 1000 900 800 0 50 100 150 200 250 300 350 400 time(hr)
Analysis Results 1800 1500 Hot-Point Temperatures (C) 1200 900 600 Hot-Point Temperature of the Core Hot-Point Temperature of the Pressure Vessel 300 Hot-Point Temperature of the Concrete Wall 0 0 400 800 1200 1600 2000 Time (hour) Figure 9: Hot-Point Temperatures
Sensitivity Analysis - Emissivity 1600 Hot-Point Temperatures (C 1200 800 Core Hot-Point Temperature (Benchmark E=0.73) Core Hot-Point Temperature(Emissivity=0.01) Core Hot-Point Temperature(Emissivity=1) 400 Wall Hot-Point Temperature (Benchmark E=0.73) Wall Hot-Point Temperature (Emmisivity=0.01) Wall Hot-Point Temperature (Emmisivity=1) 0 0 400 800 1200 1600 2000 Time (hr) Figure 11: Hot-Point Temperature Sensitivity to Emissivities of Vessel and Concrete Wall in the LOCA Analysis
Sensitivity Analysis-Conductivity Core Hot-Point Temperature 1800 . When the Conductivity of the Soil and Concrete Wall is 0.54w/m.C (Benchmark Condition) 1500 Core Hot-Point Temperature When the Conductivity of the Soil and Concrete Wall is 5w/m.C 1200 Temperature (C) Core Hot-Point Temperature When the Conductivity of the Soil and Concrete Wall is 900 10w/m.C" Concrete Wall Hot-Point Temperature When the Conductivity of the Soil and 600 Concrete Wall is 0.54w/m.C (Benchmark Condition) Concrete Wall Hot-Point Temperature When the 300 Conductivity of the Soil and Concrete Wall is 5w/m.C Concrete Wall Hot-Point 0 Temperature When the Conductivity of the Soil and 0 300 600 900 1200 1500 1800 2100 Concrete Wall is 10w/m.C Time (hr) Figure 12: Hot-Point Temperature Sensitivity to the Conductivity of Soil and Concrete Wall in the LOCA Analysis
Conclusions for LOCA Analysis • No meltdown occurs • The temperatures of the concrete wall and the steel pressure vessel are above their safety limit Explain this somewhere • The safety objectives can not been satisfied by the improvement of the thermal properties • A convective term, natural or forced, is needed to cool the concrete wall and the pressure vessel
Air Ingress Analysis Computational Fluid Dynamics • Benchmark to Japanese Diffusion, Thermal and Multi-Component Tests • Benchmark to NACOK air ingress tests • Use FLUENT CFD code to develop methodology
Experimental Apparatus - Japanese H4 C4 C3 H3 H2 C2 Helium C1 H1 Valves 2 7 0 Nitrogen Figure 16: Apparatus for Isothermal and Figure 17: Structured mesh Non-Isothermal experiments
Isothermal Experiment 0.80 0.60 Mole fraction 0.40 H-1 & C-1(Calculation) H-2 & C2 (Calculation) H-3 & C3 (Calculation) 0.20 H-4 & C4 (Calculation) H-1 & C-1(Experiment) H-2 & C2 (Experiment) H-3 & C3 (Experiment) H-4 & C4 (Experiment) 0.00 0 50 100 150 200 250 300 Time (min) Figure 18: Mole fraction of N 2 for the isothermal experiment
Thermal Experiment � Pure Helium in top pipe, pure Nitrogen in the bottom tank � N 2 Mole fractions are monitored in 8 points • Hot leg heated Figure 19: The contour of the • Diffusion Coefficients as a temperature bound4ary condition function of temperature
Thermal Experiment 1 1 H-1(FLUENT) H2(Experiment) C-1(FLUENT) C2(Experiment) H-1(Experiment) H-2(FLUENT) 0.8 C-1(Experiment) 0.8 C-2(FLUENT) Mole fraction of N2 0.6 Mole Fraction 0.6 0.4 0.4 0.2 0.2 0 0 0 50 100 150 200 0 50 100 150 200 Time (min) Time(min) Figure 20: Comparison of mole fraction of Figure 21: Comparison of mole fraction N 2 at Positions H-1 and C-1 of N 2 at Positions H-2 and C-2
Thermal Experiment (Cont.) 1 0.25 H4(Exp) C4(Exp) 0.20 0.8 H-4(Calc) Mole Fraction of N2 0.15 C-4(Calc) Velocity (m/second) 0.6 0.10 0.05 0.4 0.00 0 2 4 6 0.2 -0.05 -0.10 0 0 50 100 150 200 250 -0.15 Time(min) Time (Second) Figure 22: Comparison of mole fraction Figure 23: The vibration after the of N 2 at Positions H-1 and C-1 opening of the valves.
Multi-Component Experiment(Cont .) • Chemical Reactions – 1 surface reaction: C + O2 = x CO + y CO2 (+ Heat) E = − 0 n exp( ) r K p − 0 c o o RT 2 – 2 volume Reactions: 2 CO + O2 = 2CO2 ( + Heat) 2 CO2 = 2 CO + O2 (- Heat) Figure 35: The temperature boundary conditions for the multi-component experiment
Multi-Component Experiment(Cont.) 0.21 O2(Experiment) O2(Calculation) 0.18 CO(Experiment) CO(Calculation) 0.15 CO2(Experiment) Mole Fraction CO2(Calculation) 0.12 0.09 0.06 0.03 0.00 0 20 40 60 80 100 120 140 Time(min) Figure 36: Mole Fraction at Point-1 (80% Diffusion Coff.)
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