Water model grids

Example 3.2. Density-adjusted grid occupancy for a water model... 

FIGURE 19.1 Configuration of the 3 nautical mile model. Grid lines indicate (10x10) model cells, the bold line shows the uniform resolution area, black squares denote the model river boxes, and the gray scale corresponds to water depth in meters. 

The black oil model history match simulated a 640 acre area of the expected 2980 acre field polymer process area. The model area represented 1.5 nine-spot patterns or 12.6 percent of the expected field polymer flood area pore volume. The model grid was 13 X 39 X 5 layers (2,535 blocks) and contained 16 active wells. The model represented the light oil zone, the heavy oil zone, and the aquifer in order to match performance. The model area was chosen to exhibit a porosity thickness value, injection withdrawal ratio, and water oil ratio trend that was representative of the field. A... 

The Loss of River Water is initiated by loss of plant power grid and river water pump house equally. Response to loss of river water involves event recognition, shutdown, and water conservation. Loss of grid includes recovery modeling based on industry-wide (utility) experience... 

Modeling of water may be extended to properties involving the movement of molecules into space, a process of evaporation. For this the grid must be structured at the initial setting to have two different areas, one with occupied cells and the other with unoccupied cells (Figure 3.7). The rate of evaporation can be measured from a model allowing for water movement into an empty part of the grid. This is illustrated in Example 3.5. 

A 55 X 55 grid is used with 2100 water cells, corresponding to a density of 69%. A number of solute molecules are then added. If 100 solute molecules are used, then this number would be subtracted from the 2100 water molecules to maintain 69% cells in the grid. The assumption is made that the volume of all molecules in the grid is about 69%. This assumes that the dissolution in this study produces an overall expansion of the volume of the system to 3125 occupied cells, but we are modeling only 3025 of these as water cells. Volume expansion on addition of a solute is recognized, but it may not be a universal phenomenon. The reader is invited to explore this concept. 

The reader is invited to examine this phenomenon by running the models described above, by varying these two sets of parameters. The solute is modeled as a 10 X 10 block of 100 cells in the center of a 55 x 55 cell grid. The water content of the grid is 69% of the spaces around the solute block, randomly placed at the beginning of each run. The water temperature (WW), solute-solute afiinity (SS), and hydropathic character of the solute (WS) are presented in the parameter setup for Example 4.4. The extent of dissolution as a function of the rules and time (5000 iterations) is recorded as the fo and the average cluster size of the solute (S). 

A series of rules describing the breaking, / B,and joining, J, probabilities must be selected to operate the cellular automata model. The study of Kier was driven by the rules shown in Table 6.6, where Si and S2 are the two solutes, B, the stationary cells, and W, the solvent (water). The boundary cells, E, of the grid are parameterized to be noninteractive with the water and solutes, i.e., / b(WE) = F b(SE) = 1.0 and J(WE) = J(SE) = 0. The information about the gravity parameters is found in Chapter 2. The characteristics of Si, S2, and B relative to each other and to water, W, can be interpreted from the entries in Table 6.6. 

One of the first studies to predict log P by using potential energy fields calculated using the GRID and CoMFA approaches was done by Kim [60]. The author investigated H, CH3 and H2O probes, and calculated the best models using the hydro-phobic probe H2O for relatively small series (20 or less compounds each) of furans, carbamates, pyridines and pyrazines. A similar study was performed by Waller [61] who predicted a small series of 24 polyhalogenated compounds. Recently, Caron and Ermondi [62] used a new version of Cruciani s software, VolSurf [63], to predict the octanol-water and alkane-water partition coefficients for 152 compounds with r = 0.77, q = 0.72, SDEP = 0.60 for octanol-water and r = 0.76, q = 0.71, SDEP = 0.85 for alkane-water. 

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