Tutorials Manual

More documents

Recommendations

Info

Chemkin 4.1.1 Chapter 4: Materials Problems 4.2.1.2.1 Transient PSR The names of the flow-profile files are designated on the Stream Property Data tab of each Gas Inlet panel. If a profile file already exists, it can be selected by browsing or by the pull-down menu, if it has already been accessed. The Edit button opens a panel that allows profile files to be edited or created. In this case, inlet temperatures are not specified on the Gas Inlet panel, as this is a fixed-gas temperature simulation. The composition of each reactant gas inlet is specified on the Species-specific Property panel of the corresponding Gas Inlet panel. The choice of fixed gas temperature for this simulation is made with the Problem-type dropdown list on the Reactor Physical Property tab of the C1_ PSR panel. The gas temperature, pressure, volume and surface area (which are generally representative of ALD reactors) are also input here. In this case, the gas temperature for the PSR simulation was chosen to reproduce the degree of ozone decomposition to O atoms and match the deposition rate observed in the higher dimensional simulation. The surface temperature is different from the gas temperature, and it is also specified on the Reactor Physical Properties tab. On the Species-specific Data tab, the starting gas composition of pure argon is specified on the Initial Gas Fraction sub-tab, the starting surface composition of complete O(S) coverage is specified on the Surface Fraction sub-tab, and an activity of 1.0 specified for AL2O3(B) on the Bulk Activity sub-tab. These correspond to a reasonable starting condition where the substrate might have an initial oxide coating, and the system was purged with argon after loading. No entries are made on the other parts of this panel. The end time of the transient simulation is specified on the Basic tab of the Solver panel, along with the solver step time, interval for saving the solution, and the interval for printing data to the diagnostic output file. No entries are needed on the Output Control or Continuations panels for this problem. 4.2.1.2.2 Transient Stagnation Flow Reactor The names of the flow-profile files are designated on the Stream-property panel of each Gas Inlet panel. In this case, the gas energy equation is being solved, so inlet temperatures of 150° C (423 K) are input for each gas inlet. The composition of each reactant gas inlet is specified on the Species-specific Property tab of the corresponding Gas Inlet panel. Choices to solve a transient problem, include the gas energy equation, use multicomponent diffusion but not the Soret effect, etc., are input in the Reactor Physical Property tab, Basic sub-tab of the C1_ Stagnation Flow panel. The process pressure and surface temperature are input on this sub-tab, along with the name of © 2007 Reaction Design 136 RD0411-C20-000-001
Chapter 4: Materials Problems <strong>Tutorials</strong> <strong>Manual</strong> file containing the initial guess for the gas temperatures as a function of height above the disk, and a cross sectional flow area used for translating volumetric flow rates to linear flow velocities. There are no entries on the other sub-tabs of the Reactor Physical Property tab. The Initial Grid Property tab of the C1_ Stagnation Flow panel allows the input of the number of points in the grid of distance above the substrate, along with the ending axial distance. In transient simulations, the grid currently does not adapt as it does in steady-state stagnation flow simulations. Thus, a reasonably dense initial grid should be specified, and the adaptive gridding parameters are ignored. Note that the surface is defined as being at a coordinate value of x = 0, and the maximum distance of 1.2 cm is the location of the gas inlets (showerhead). In other words, the solution is given as a function of distance from the surface. On the Species-specific Data tab of the C1_ Stagnation Flow panel, the starting gas composition of pure argon is specified on the Initial Gas Fraction sub-tab, the starting surface composition of complete O(S) coverage is specified on the Surface Fraction sub-tab and an activity of 1.0 specified for AL2O3(B) on the Bulk Activity sub-tab. These are the same as were used in the PSR simulation, and correspond to a reasonable starting condition where the substrate might have an initial oxide coating, and the system was purged with argon after loading. No entries are made on the other parts of this panel. The end time of the transient simulation is specified on the Basic tab of the Solver panel, along with the interval for printing data to the output file and some tolerance parameters that have been relaxed from the default values. The Advanced tab of the Solver panel contains a time-step specification and a solver parameter that have been altered from the default values. No entries are made on the Output Control or Continuations panels for this problem. 4.2.1.3 Project Results Figure 4-19 shows the gas pulses used in this example for the metal-organic and oxidizer gas inlets. The pure-argon purge gas pulses are not shown. The metalorganic gas pulses are considerably shorter than the oxidizer gas pulses, but appear to be sufficient. The contour plot of one TMA pulse from the stagnation-flow simulation in Figure 4-20 clearly shows that the TMA is consumed at the surface only at the beginning of the pulse. By the end of the pulse, all the TMA flowing into the reactor is also flowing out again. RD0411-C20-000-001 137 © 2007 Reaction Design
Page 1 and 2:
August 3, 2007 1:53 am Release 4.1.
Page 3 and 4:
Chemkin 4.1.1 Contents Table of Con
Page 5 and 6:
Chemkin 4.1.1 Tables List of Tables
Page 7 and 8:
Tutorials Manual 4.1.1 Figures List
Page 9 and 10:
List of Figures Tutorials Manual 2-
Page 11 and 12:
List of Figures Tutorials Manual 4-
Page 13 and 14:
Chemkin 4.1.1 1 1 Introduction The
Page 15 and 16:
Chapter 1: Introduction Tutorials M
Page 17 and 18:
Chemkin 4.1.1 2 2 Combustion in Gas
Page 19 and 20:
Chapter 2: Combustion in Gas-phase
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
Page 63 and 64:
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
Page 71 and 72:
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
Page 79 and 80:
Page 81 and 82:
Page 83 and 84:
Page 85 and 86: Chapter 2: Combustion in Gas-phase
Page 91 and 92: Chemkin 4.1.1 3 3 Catalytic Process
Page 93 and 94: Chapter 3: Catalytic Processes Tuto
Page 115 and 116: Chemkin 4.1.1 4 4 Materials Problem
Page 117 and 118: Chapter 4: Materials Problems Tutor
Page 135: Chapter 4: Materials Problems Tutor
Page 161 and 162: Chemkin 4.1.1 5 5 Chemical Mechanis
Page 163 and 164: Chapter 5: Chemical Mechanism Analy
Page 177 and 178: Tutorials Manual 4.1.1 Index Index
Page 179 and 180: Index Tutorials Manual normalized s
show all

Tutorials Manual

Create successful ePaper yourself

Delete template?

Save as template?