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Q3drm1.0/2.0软件的主要技术展示
1. Map-Boundary Positioning
After determining the required number of grid layers (NGR ≤ 6), the user can prepare to generate corresponding grids.
Q3drm1.0 software uses a series of short straight lines to describe theirregular boundaries (Side-I and Side-II) along the flow direction ofcomputational domain; these short lines, however, divide the water body intoseveral segment (subsection) with the same or proximate hydraulic characteristics.
Except for the regular or simple computational domain, which boundary coordinates and characteristic values for the most coarse grid can be entered through tables (the number of nodal pointson two boundaries, including two end-points NLrs ≤ 21), in general, the user should locate the irregular boundaries of the most coarse grid by operating themouse on digital map, and enter the corresponding parameters for each short line on appeared tables. Q3drm1.0 software allows users to use no more than two subsections for describing the inlet of an import tributary; and provides the function to input ‘the desired value’ of averaged spacing between two transversal grid lines to help users quickly estimating the cell number for each subsection; and also provide special dialog box, table and the ‘re-drawing'skill for locating the islands and bifurcate entrance. The nodal points ontransverse grid lines of body-fitted coordinate system, generated by Q3drm1.0 software, can be uniform (ITA= 0) and also can be non-uniform distribution (ITA = 1); the internal nodal points of body-fitted coordinate system can be through a smooth (LSMOOTH = T) or not through the smooth (LSMOOTH = F).
The following Figures show four location images,drawn on digital map or topographic map for positing boundaries of complex computational domains: a. meandering river reach (NLrs=82); b. cooling pond with single island (NLrs=83); c. natural river reach with multiple islands (two islands, NLrs=56); d. natural river reach with bifurcated entrance and multiple islands (two islands, NLrs=54).
2. Treatmentof Point-Source Discharge and Point-Sink as well as Area-Source Discharge
In addition to likethe general quasi 3D modeling tools, which can handle relatively simple side discharge problems, Q3drm1.0 software, however, has the strong ability to deal with point-source discharge (such as submerged single hole diffuser and multiport diffusers) and point-sink (such as submerged intake) as well as area-source discharge. Q3drm1.0 software uses Pantankar’s source-term linearization method and Rodi’s vertical linear source concept to describe point-source and point-sink; and also arranges a series of source points at the nodal points of control volume centers to deal with the area-source discharge from the slope along bank. The current version of the software allows settingup to 500 (NPS=500) point-sources (flow-rate QPS>0) and/or point-sinks (flow-rate QPS<0). Either for point-source or point-sink, besides that the location type (IPSTYPE: the value of this parameter determines the position of point-source or point-sink in the divided cell of finer grid), i- and j-index (IPS and JPS), flow-rate (QPS), temperature (TPS), concentration component-1 (C1PS) and concentration component-2 (C2PS) have to be identified and entered for each source/sink, users also need to specify the two jet direction angles β (ABET) and α(ARFA), where β means the inclination between jet-direction and horizontal planeand α is the angle between the horizontal project of jet-direction and X-direction, respectively.
Following Figures display four 3-D contaminant concentration fields, drawn on digital map or topographic map, caused by various types of discharges: a. single side discharge; b. side discharge from two banks; c. submerged five-port diffuser; d. area-source discharge from right-side slope along South bank.
3. Display of Generated Grids
After using the technology of Map-Boundary Positioning, determining the grid parameters and producing the Jobname.GIN file for grid generation, the user can call Q3drm1.0’s grid-generator: GridI.exe or GridJ.exe to generate automatically all levels of grids, from the designed most coarse grid to the finest grid. Q3drm1.0 software also can provide users with the grid browser to display the generated grids. Following Figures demonstrate four non-orthogonal body-fitted multi-grids, drawn on digital maps, in a reach of Amazon River near the Manaus City, Brazil, which include large and small seven islands and the imported largest black water river worldwide (i.e.The Black Water River, the number of grid levels NGR=2), where a. and b. are the coarse and fine grids, in which the imported black water river does not be considered in the computational domain; and c. and d. are the coarse and fine grids of the bifurcated computational domain, including the imported tributary.
4. 2-D Display of Calculated Variables
The profile browser and field browser of Q3drm1.0 software can display and analyze 2-D graphics of calculated variables. The calculated variables, however, include velocity, pressure, temperature, two concentration components, two turbulence parameters, effective viscosity, production term of turbulent kinetic energy and bottom topography, respectively. For the calculated velocity, the graphics of flow pattern (vector distribution diagram), velocity profiles, streamlines and flow field can be generated. Following Figures illustrate eight 2-D graphics of calculated results drawn on digital maps, for a reach of Yangtze River, China: a. velocity pattern; b. streamlines; c. flow field; d. isobars; e. pressure field; f.concentration contours; g. concentration field and h. effective viscosity field, respectively.
5. 3-D Display of Calculated Variables
The 3D browser of Q3drm1.0 software can display and analyze 3-D graphics of calculated seven variables. The seven variables, however, are temperature, two concentration components, two turbulence parameters, effective viscosity and production term of turbulent kinetic energy, respectively. Users can try to use different values of α1 and α2 angles to draw the three-dimensional view with different perspective effects. Following Figures express five 3-Dgraphics of calculated results drawn on digital maps, for a reach of Amazon River, near the Manaus City, Brazil: a. concentration; b. turbulence parameter k; c. turbulence parameter omega; d. effective viscosity and e. production term of turbulent kinetic energy, respectively.
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