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หน้า 3 จาก 8
Figure 4. Computed FEA results for inboard seal faces nearest impeller. Figure 5 shows a cutaway view of a cylindrical flow domain and structured finite-volume grid used to conduct 3D flow analyses for a tapered surface design (Figure 2). The dark blue axially centered region of the mesh represents the surface through which fluid enters the domain. The corresponding outlet surface (not shown) is likewise axially centered in the flow channel region, and displaced about 60 degrees circumferentially in the clockwise direction from the inlet. 
Figure 5. Gridded flow domain used for typical CFD analysis of barrier fluid. A typical set of boundary conditions used for the CFD analyses are depicted in Figures 6, 7, and 8. Figure 6 illustrates the rotating velocity boundaries (shown in yellow). These boundaries consist of the outer radial surface of the sleeve, the bounding surfaces defined by the carbon-graphite faces, and the thin fluid surfaces between the sleeve and the rotating faces (Figure 2). The stationary (non-rotating) boundaries, as well as the flow 
Figure 6. Velocity boundary conditions used for barrier fluid flow analysis. cross-sections, are shown in blue. Figure 7 shows the temperature boundary conditions used for the tapered surface design analyses. These temperatures represent average surface values obtained from the FEA model (Figure 4). Note that the boundary temperatures are higher for the outboard side of the domain (background). The adiabatic heat flux boundary conditions assumed for the stainless steel sleeve, the outer radial surface of the stainless 
Figure 7. Temperature boundary conditions obtained from FEA model. steel flow channel, the region of recirculation between the inlet and outlet ports, and the axial fluid ends of the domain are depicted in Figure 8. The assumption of negligible heat exchange across the stainless steel surfaces was invoked because of the order-of-magnitude lower value of thermal conductivity for stainless steel compared with that of the silicon carbide seal face material.
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