# A Heuristic Method for Modeling Odor Emissions from Open Roof Rectangular Tanks

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Material and Methods

#### 2.1. Passive Odor Sources

^{2}/s. The SOER is determined by the product of the odor concentration (C

_{Od}, ouE/m

^{3}) and the volumetric flow rate (Q, m

^{3}/s) within the sampling device, divided by its area (A

_{B}, m

^{2}):

^{2}):

_{R}, m/s) within the sampling device (e.g., a wind tunnel). Since the flow rate is a function of the air speed within the sampling device, when simulating odor emissions, one must consider the wind speed over the source area. As indicated by [22], the odor emission rate over the emitting surface (OER

_{S}) can be calculated as:

_{s}(m/s) is the wind speed close to the surface of the odor source, and it can be calculated with a power law profile as

_{h}(m/s), and z (m) is the height at which the wind is estimated.

_{s}in Equation (4) represents the wind speed at the top of the tank; however, it is typically higher than the wind speed close to the emitting surface, which is responsible for “stripping” the odorous molecules. On the other hand, assuming z equal to the height of the emitting surface is not correct when the surface is well within the tank.

#### 2.2. Wind Speed over the Emitting Surface

_{R}, without any correction for wind speed or wind direction.

_{L}) must decrease as the distance DTL increases. It is assumed that v

_{L}can be described with a logarithmic profile, as done, for example, by [29] within a street canyon:

_{0}is the height above the odor-emitting surface at which the wind speed is evaluated; in the following calculations, it is set to 0.1 m. For the roughness length z

_{0}

_{,}a value of 0.01 m is used, assuming a mud-like surface. This roughness length value was chosen considering, for example, a manure tank or an aerobic sludge digestion tank. Of course, the value may be different when the tank contains mainly water. An estimate of the uncertainties due to the choice of z

_{0}and other variables is reported in paragraph 3.4.

_{L}. For this reason, the wind speed correction should be applied only when the DTL exceeds a certain threshold value, for example when the DTL > h

_{0}. When the DTL is smaller than such a value, it is assumed that the wind speed does not change (i.e., the value at tank top is used).

#### 2.3. The LAPMOD Dispersion Model

#### 2.4. Meteorology

^{2}, with a grid resolution of 200 m. The WRF output of its innermost domain was used in input by CALMET as surface and upper air data. The 1-h CALMET output data of the computational grid containing the source were extracted for the whole simulation year (2020). These data are used in input by the emission processor implementing the equations described in the previous sections. They were also used to prepare the wind rose shown in Figure 7.

#### 2.5. Source Term

^{2}and different shape factors (L/W) were considered (Table 2). All the tanks had a height of 3 m above the ground and the same centroid. For each tank, two different orientations (90 and 180 degrees) and four DTLs were considered, as summarized in Table 3. As already specified, DTL means the distance between the tank top and the emitting surface within the tank (see Figure 2).

#### 2.6. Simulation Domain

^{2}with a distance of 50 m from each other. Discrete receptors were placed at the intersections of two circles (centered over the common centroids of the sources with radius of 500 m and 1000 m) with the segments exiting from the centroid of the sources with angles from 0 to 360 degrees with steps of 45 degrees (where 0 degrees is north). Therefore, a total of 16 discrete receptors was used. All the receptors, regular and discrete, were placed 2 m above ground level.

## 3. Results and Discussion

#### 3.1. Emissions

#### 3.2. Separation Distances

^{3}, 3 ouE/m

^{3}and 5 ouE/m

^{3}and exceedance probability of 2%. In other words, the 98th percentile of the peak concentrations at any output point should be lower than the threshold levels. As pointed out by [35], separation distances are described by the contour lines of an ambient concentration threshold at a fixed exceedance probability of such a threshold. The exceedance probability of 2% corresponds to 176 h, since a leap-year (2020) was simulated.

_{S}for two identical tanks with same area and shape factor (L/W), but different orientations, is calculated with Equation (3), which does not consider the wind direction and distance between the tank top and the emitting surface (DTL = 0.0 m).

_{T,DTL}-D

_{T,0.0})/D

_{T,0.0}× 100, where D

_{T,DTL}represents the maximum separation distance along X or Y for orientation T and a specific DTL, and D

_{T,0.0}represents the maximum separation distance along X or Y for orientation T and DTL = 0.0 m.

_{180}− D

_{90})/D

_{90}× 100, where D

_{T}represents the maximum separation distance along X or Y for orientation T.

_{T}= 1 ouE/m

^{3}when DTL = 0.5 m (Figure 10G) and DTL = 1.0 m (Figure 10D). In both situations, when the tank orientation was 180 degrees, the maximum separation distance along X (to the left of the source) reduces by about 30 m, while the maximum separation distance along Y increases by about 5 m.

_{T}= 1 ouE/m

^{3}the maximum separation distance along X decreases from −1.7% to −6.1% going from DTL = 0.5 m (Figure 11D) to DTL = 1.5 m (Figure 11J) when the two different orientations are considered (Table 8). On the contrary, in the same situation, the maximum separation distance along Y increases from 1.2% to 5.5%. A similar behavior (i.e., reduction of the maximum separation distance along X and increase along Y) is observed for C

_{T}= 3 ouE/m

^{3}and C

_{T}= 5 ouE/m

^{3}. Table 7 shows that the reduction of the maximum separation distance as the only variation of the DTL for a fixed orientation reaches a maximum of −16.2% along X (DTL = 1.5 m, orientation 180°, C

_{T}= 1 ouE/m

^{3}) and −19.6% along Y (DTL = 1.5 m, orientation 90°, C

_{T}= 3 ouE/m

^{3}).

_{T}= 1 ouE/m

^{3}) and −20.0% along Y (DTL = 1.5 m, orientation 90°, C

_{T}= 1 ouE/m

^{3}). Concerning the variation due to tank orientation for a fixed DTL value, Table 8 shows that, for C

_{T}= 1 ouE/m

^{3}, the maximum variation along X is −8.7% when DTL = 1.0 m (Figure 12G), while it is −6.6% when DTL = 1.5 m (Figure 12J).

_{T}= 3 ouE/m

^{3}and C

_{T}= 5 ouE/m

^{3}. These results, as discussed for the emissions, are due to the larger variation of the average wind speed over the emitting surface when passing from DTL = 0.5 m to DTL = 1.0 m than when passing from DTL = 1.0 m to DTL = 1.5 m.

_{T}= 1 ouE/m

^{3}) and −20.0% along Y (DTL = 1.5 m, orientation 90°, C

_{T}= 1 ouE/m

^{3}). Table 8 shows the variation of the maximum separation distance due to tank orientation for a fixed DTL value shows results qualitatively similar to those of tank L15_W6. For C

_{T}= 1 ouE/m

^{3}, the variation of the maximum separation distance along X is −10.2% when DTL = 1.0 m (Figure 13G), while it is −6.6% when DTL = 1.5 m (Figure 13J).

_{T}= 3 ouE/m

^{3}and C

_{T}= 5 ouE/m

^{3}. Again, these effects are due to the different variations of the average wind speed over the emitting surface when passing from DTL = 0.5 m to DTL = 1.0 m than when passing from DTL = 1.0 m to DTL = 1.5 m.

#### 3.3. Results at Discrete Receptors

^{th}percentile values with respect to DTL = 0.0 m are −7.4% (DTL = 0.5 m), −17.7% (DTL = 1.0 m) and −37.5% (DTL = 1.5 m), and when the orientation is 180 degrees, the relative variations with respect to DTL = 0.0 m are −18.7% (DTL = 0.5 m), −37.5% (DTL = 1.0 m) and −40.0% (DTL = 1.5 m). Therefore, for a tank shape factor significantly different from 1, the relative variations for the same DTL value are very different as a function of the tank orientation.

#### 3.4. Evaluation of Uncertainties

- The proportionality factor (k = 3) between the DTL and the distance of the impingement point from the leading edge, or the distance from the separation point and the trailing edge of the cavity, used in Equation (6).
- The roughness length (z
_{0}= 0.01 m) used in Equation (5) for determining the flow velocity close to the emitting surface. - The height (h
_{0}= 0.1 m) above the odor-emitting surface at which the wind speed is evaluated, Equation (5). - The correction factor (μ = 0.8) used in Equation (5) for determining the flow velocity close to the emitting surface.

_{0}, (0.05 and 0.15 m) for h

_{0}, (2.5 and 3.5) for k and (0.7 and 0.9) for μ.

_{0}= 0.01 m, h

_{0}= 0.1 m and μ = 0.8 (the values used in this work), as reported in the rightmost column of Table 9. The calculated value is always within the interval determined by the mean plus or minus a standard deviation. For each tank, the standard deviation (i.e., the uncertainty) increases with the DTL. This is likely due to the fact that, when the DTL is small, the area characterized by free flow is large (Figure 1, center), and over this area, there are no constants involved in determining the flow, since it is the external one. On the contrary, when the DTL increases, the four parameters play a role.

## 4. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 2.**Simple schematization of the rectangular tank. The gray surface represents the emitting surface.

**Figure 6.**Wind path approximation. P is represented by the dashed black lines, while Pa is represented by the blue dashed lines.

**Top**: the wind vector enters and exits through L.

**Bottom**: the wind vector enters and exits through W.

**Figure 8.**Annual emissions of odor (10

^{9}ouE/year) for the different tanks and scenarios. (

**A**): tank L10_W9, shape factor 1.11. (

**B**): tank L12_W7.5, shape factor 1.60. (

**C**): tank L15_W6, shape factor 2.50. (

**D**): tank L18_W5, shape factor 3.60.

**Figure 9.**Box and whiskers plot of the OERs (ouE/s) for the different tanks and scenarios. The green circle represents the mean value, while the red segment represents the median value. The mean and median values are also numerically reported in the upper part of the figure. (

**A**): tank L10_W9, shape factor 1.11. (

**B**): tank L12_W7.5, shape factor 1.60. (

**C**): tank L15_W6, shape factor 2.50. (

**D**): tank L18_W5, shape factor 3.60.

**Figure 10.**Tank L10_W9. Separation distances calculated for the base case (top row) and as a function of the tank orientation and DTL of 0.5 m (second row), 1.0 m (third row) and 1.5 m (bottom row). Concentration thresholds are 1 ouE/m

^{3}(left column), 3 ouE/m

^{3}(central column) and 5 ouE/m

^{3}(right column). The dark green circle represents the centroid of the sources, while the black crosses represent the discrete receptors. (

**A**): DTL = 0.0 m, C

_{T}= 1 ouE/m

^{3}. (

**B**): DTL = 0.0 m, C

_{T}= 3 ouE/m

^{3}. (

**C**): DTL = 0.0 m, C

_{T}= 5 ouE/m

^{3}. (

**D**): DTL = 0.5 m, C

_{T}= 1 ouE/m

^{3}. (

**E**): DTL = 0.5 m, C

_{T}= 3 ouE/m

^{3}. (

**F**): DTL = 0.5 m, C

_{T}= 5 ouE/m

^{3}. (

**G**): DTL = 1.0 m, C

_{T}= 1 ouE/m

^{3}. (

**H**): DTL = 1.0 m, C

_{T}= 3 ouE/m

^{3}. (

**I**): DTL = 1.0 m, C

_{T}= 5 ouE/m

^{3}. (

**J**): DTL = 1.5 m, C

_{T}= 1 ouE/m

^{3}. (

**K**): DTL = 1.5 m, C

_{T}= 3 ouE/m

^{3}. (

**L**): DTL = 1.5 m, C

_{T}= 5 ouE/m

^{3}.

**Figure 11.**Tank L12_W7.5. Separation distances calculated for the base case (top row) and as a function of the tank orientation and DTL of 0.5 m (second row), 1.0 m (third row) and 1.5 m (bottom row). Concentration thresholds are 1 ouE/m

^{3}(left column), 3 ouE/m

^{3}(central column) and 5 ouE/m

^{3}(right column). The dark green circle represents the centroid of the sources, while the black crosses represent the discrete receptors. (

**A**): DTL = 0.0 m, C

_{T}= 1 ouE/m

^{3}. (

**B**): DTL = 0.0 m, C

_{T}= 3 ouE/m

^{3}. (

**C**): DTL = 0.0 m, C

_{T}= 5 ouE/m

^{3}. (

**D**): DTL = 0.5 m, C

_{T}= 1 ouE/m

^{3}. (

**E**): DTL = 0.5 m, C

_{T}= 3 ouE/m

^{3}. (

**F**): DTL = 0.5 m, C

_{T}= 5 ouE/m

^{3}. (

**G**): DTL = 1.0 m, C

_{T}= 1 ouE/m

^{3}. (

**H**): DTL = 1.0 m, C

_{T}= 3 ouE/m

^{3}. (

**I**): DTL = 1.0 m, C

_{T}= 5 ouE/m

^{3}. (

**J**): DTL = 1.5 m, C

_{T}= 1 ouE/m

^{3}. (

**K**): DTL = 1.5 m, C

_{T}= 3 ouE/m

^{3}. (

**L**): DTL = 1.5 m, C

_{T}= 5 ouE/m

^{3}.

**Figure 12.**Tank L15_W6. Separation distances calculated for the base case (top row) and as a function of the tank orientation and DTL of 0.5 m (second row), 1.0 m (third row) and 1.5 m (bottom row). Concentration thresholds are 1 ouE/m

^{3}(left column), 3 ouE/m

^{3}(central column) and 5 ouE/m

^{3}(right column). The dark green circle represents the centroid of the sources, while the black crosses represent the discrete receptors. (

**A**): DTL = 0.0 m, C

_{T}= 1 ouE/m

^{3}. (

**B**): DTL = 0.0 m, C

_{T}= 3 ouE/m

^{3}. (

**C**): DTL = 0.0 m, C

_{T}= 5 ouE/m

^{3}. (

**D**): DTL = 0.5 m, C

_{T}= 1 ouE/m

^{3}. (

**E**): DTL = 0.5 m, C

_{T}= 3 ouE/m

^{3}. (

**F**): DTL = 0.5 m, C

_{T}= 5 ouE/m

^{3}. (

**G**): DTL = 1.0 m, C

_{T}= 1 ouE/m

^{3}. (

**H**): DTL = 1.0 m, C

_{T}= 3 ouE/m

^{3}. (

**I**): DTL = 1.0 m, C

_{T}= 5 ouE/m

^{3}. (

**J**): DTL = 1.5 m, C

_{T}= 1 ouE/m

^{3}. (

**K**): DTL = 1.5 m, C

_{T}= 3 ouE/m

^{3}. (

**L**): DTL = 1.5 m, C

_{T}= 5 ouE/m

^{3}.

**Figure 13.**Tank L18_W5. Separation distances calculated for the base case (top row) and as a function of the tank orientation and DTL of 0.5 m (second row), 1.0 m (third row) and 1.5 m (bottom row). Concentration thresholds are 1 ouE/m

^{3}(left column), 3 ouE/m

^{3}(central column) and 5 ouE/m

^{3}(right column). The dark green circle represents the centroid of the sources, while the black crosses represent the discrete receptors. (

**A**): DTL = 0.0 m, C

_{T}= 1 ouE/m

^{3}. (

**B**): DTL = 0.0 m, C

_{T}= 3 ouE/m

^{3}. (

**C**): DTL = 0.0 m, C

_{T}= 5 ouE/m

^{3}. (

**D**): DTL = 0.5 m, C

_{T}= 1 ouE/m

^{3}. (

**E**): DTL = 0.5 m, C

_{T}= 3 ouE/m

^{3}. (

**F**): DTL = 0.5 m, C

_{T}= 5 ouE/m

^{3}. (

**G**): DTL = 1.0 m, C

_{T}= 1 ouE/m

^{3}. (

**H**): DTL = 1.0 m, C

_{T}= 3 ouE/m

^{3}. (

**I**): DTL = 1.0 m, C

_{T}= 5 ouE/m

^{3}. (

**J**): DTL = 1.5 m, C

_{T}= 1 ouE/m

^{3}. (

**K**): DTL = 1.5 m, C

_{T}= 3 ouE/m

^{3}. (

**L**): DTL = 1.5 m, C

_{T}= 5 ouE/m

^{3}.

**Figure 14.**The 98th percentiles of peak concentrations (ouE/m

^{3}) at discrete receptors for the eight emission scenarios.

Stability Class | Rural Terrain | Urban Terrain |
---|---|---|

A | 0.07 | 0.15 |

B | 0.07 | 0.15 |

C | 0.10 | 0.20 |

D | 0.15 | 0.25 |

E | 0.35 | 0.30 |

F | 0.55 | 0.30 |

Tank | Length (m) | Width (m) | L/W |
---|---|---|---|

L10_W9 | 10.0 | 9.0 | 1.11 |

L12_W7.5 | 12.0 | 7.5 | 1.60 |

L15_W6 | 15.0 | 6.0 | 2.50 |

L18_W5 | 18.0 | 5.0 | 3.60 |

Parameter | Value |
---|---|

Height (m) | 3 |

DTLs (m) | 0.0, 0.5, 1.0, 1.5 |

Orientations (degrees) | 90, 180 |

SOER (ouE/m^{2}/s) | 80 |

DTL (m) | L10_W9 (%) | L12_W7.5 (%) | L15_W6 (%) | L18_W5 (%) |
---|---|---|---|---|

0.0 | 0.0 | 0.0 | 0.0 | 0.0 |

0.5 | 0.5 | 2.2 | 4.5 | 6.2 |

1.0 | 0.8 | 3.7 | 12.2 | 13.2 |

1.5 | 0.9 | 6.9 | 7.9 | 7.6 |

Tank | Wind from N or S | Wind from E or W | Ratio |
---|---|---|---|

T90_L18_W5 DTL0.5 | 120,431 | 132,688 | 1.10 |

T180_L18_W5 DTL0.5 | 135,547 | 115,769 | 0.85 |

T90_L18_W5 DTL1.0 | 92,659 | 121,976 | 1.32 |

T180_L18_W5 DTL1.0 | 120,043 | 88,844 | 0.74 |

T90_L18_W5 DTL1.5 | 88,831 | 109,379 | 1.23 |

T180_L18_W5 DTL1.5 | 100,162 | 85,174 | 0.85 |

Tank | Wind from N or S | Wind from E or W | Ratio |
---|---|---|---|

T90_L18_W5 DTL0.5 | 44,425 | 64,633 | 1.45 |

T180_L18_W5 DTL0.5 | 50,364 | 56,966 | 1.13 |

T90_L18_W5 DTL1.0 | 34,138 | 58,231 | 1.71 |

T180_L18_W5 DTL1.0 | 45,301 | 43,770 | 0.97 |

T90_L18_W5 DTL1.5 | 32,728 | 50,221 | 1.53 |

T180_L18_W5 DTL1.5 | 38,940 | 41,962 | 1.08 |

**Table 7.**Relative variation (%) of the maximum separation distances along X and Y as a function of the DTL. Or. is tank orientation.

C_{T} = 1 ouE/m^{3} | C_{T} = 3 ouE/m^{3} | C_{T} = 5 ouE/m^{3} | ||||||
---|---|---|---|---|---|---|---|---|

Tank | Or. (degrees) | DTL (m) | ΔX (%) | ΔY (%) | ΔX (%) | ΔY (%) | ΔX (%) | ΔY (%) |

L10_W9 | 90 | 0.5 | −4.3 | −4.4 | −3.1 | −6.9 | −2.7 | −4.2 |

L10_W9 | 180 | 0.5 | −7.0 | −3.3 | −3.1 | −6.9 | −2.7 | −4.2 |

L10_W9 | 90 | 1.0 | −9.1 | −13.3 | −8.5 | −13.8 | −8.2 | −14.6 |

L10_W9 | 180 | 1.0 | −11.8 | −12.2 | −8.5 | −13.8 | −8.2 | −14.6 |

L10_W9 | 90 | 1.5 | −16.0 | −17.8 | −14.6 | −17.2 | −14.5 | −20.8 |

L10_W9 | 180 | 1.5 | −16.0 | −17.8 | −14.6 | −17.2 | −14.5 | −20.8 |

L12_W7.5 | 90 | 0.5 | −2.7 | −4.4 | −2.3 | −3.6 | −3.6 | −4.3 |

L12_W7.5 | 180 | 0.5 | −4.3 | −3.3 | −2.3 | −3.6 | −3.6 | −4.3 |

L12_W7.5 | 90 | 1.0 | −7.6 | −13.3 | −6.2 | −14.3 | −7.2 | −10.9 |

L12_W7.5 | 180 | 1.0 | −11.4 | −12.2 | −8.5 | −12.5 | −9.0 | −10.9 |

L12_W7.5 | 90 | 1.5 | −10.8 | −18.9 | −10.1 | −19.6 | −10.8 | −17.4 |

L12_W7.5 | 180 | 1.5 | −16.2 | −14.4 | −13.2 | −14.3 | −15.3 | −15.2 |

L15_W6 | 90 | 0.5 | −4.8 | −4.4 | −0.8 | −7.0 | −1.8 | −6.5 |

L15_W6 | 180 | 0.5 | −7.0 | −3.3 | −4.7 | −7.0 | −5.4 | −4.3 |

L15_W6 | 90 | 1.0 | −7.5 | −15.6 | −5.4 | −15.8 | −5.4 | −13.0 |

L15_W6 | 180 | 1.0 | −15.5 | −11.1 | −14.0 | −12.3 | −13.5 | −10.9 |

L15_W6 | 90 | 1.5 | −10.7 | −20.0 | −8.5 | −19.3 | −9.0 | −17.4 |

L15_W6 | 180 | 1.5 | −16.6 | −16.7 | −14.0 | −15.8 | −14.4 | −15.2 |

L18_W5 | 90 | 0.5 | −1.6 | −7.8 | −2.3 | −8.8 | −1.8 | −8.7 |

L18_W5 | 180 | 0.5 | −5.9 | −4.4 | −7.7 | −3.5 | −6.4 | −4.3 |

L18_W5 | 90 | 1.0 | −4.9 | −16.7 | −5.4 | −17.5 | −5.5 | −15.2 |

L18_W5 | 180 | 1.0 | −14.6 | −12.2 | −14.6 | −10.5 | −12.7 | −10.9 |

L18_W5 | 90 | 1.5 | −9.7 | −20.0 | −9.2 | −17.5 | −9.1 | −15.2 |

L18_W5 | 180 | 1.5 | −15.7 | −16.7 | −15.4 | −12.3 | −13.6 | −13.0 |

**Table 8.**Relative variation (%) of the maximum separation distances along X and Y as a function of the tank orientation.

C_{T} = 1 ouE/m^{3} | C_{T} = 3 ouE/m^{3} | C_{T} = 5 ouE/m^{3} | |||||
---|---|---|---|---|---|---|---|

Tank | DTL (m) | ΔX (%) | ΔY (%) | ΔX (%) | ΔY (%) | ΔX (%) | ΔY (%) |

L10_W9 | 0.5 | −2.8 | 1.2 | 0.0 | 0.0 | 0.0 | 0.0 |

L10_W9 | 1.0 | −2.9 | 1.3 | 0.0 | 0.0 | 0.0 | 0.0 |

L10_W9 | 1.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |

L12_W7.5 | 0.5 | −1.7 | 1.2 | 0.0 | 0.0 | 0.0 | 0.0 |

L12_W7.5 | 1.0 | −4.1 | 1.3 | −2.5 | 2.1 | −1.9 | 0.0 |

L12_W7.5 | 1.5 | −6.1 | 5.5 | −3.4 | 6.7 | −5.1 | 2.6 |

L15_W6 | 0.5 | −2.2 | 1.2 | −3.9 | 0.0 | −3.7 | 2.3 |

L15_W6 | 1.0 | −8.7 | 5.3 | −9.0 | 4.2 | −8.6 | 2.5 |

L15_W6 | 1.5 | −6.6 | 4.2 | −5.9 | 4.3 | −5.9 | 2.6 |

L18_W5 | 0.5 | −4.4 | 3.6 | −5.5 | 5.8 | −4.6 | 4.8 |

L18_W5 | 1.0 | −10.2 | 5.3 | −9.8 | 8.5 | −7.7 | 5.1 |

L18_W5 | 1.5 | −6.6 | 4.2 | −6.8 | 6.4 | −5.0 | 2.6 |

**Table 9.**The range of variation of odor emissions (ouE/s) with the bootstrap procedure and as calculated with k = 3, z

_{0}= 0.01 m, h

_{0}= 0.1 m and μ = 0.8.

Tank | Or. (degrees) | DTL (m) | Mean (ouE/s) | Median (ouE/s) | Min (ouE/s) | Max (ouE/s) | StdDev (ouE/s) | Calculated (ouE/s) |
---|---|---|---|---|---|---|---|---|

L10_W9 | 90 | 0.5 | 41,691 | 41,730 | 39,328 | 43,251 | 684 | 41,767 |

L10_W9 | 90 | 1.0 | 36,288 | 36,415 | 31,091 | 39,967 | 1528 | 36,429 |

L10_W9 | 90 | 1.5 | 27,370 | 27,604 | 20,275 | 33,146 | 2388 | 29,891 |

L10_W9 | 180 | 0.5 | 41,258 | 41,315 | 38,950 | 43,141 | 763 | 41,326 |

L10_W9 | 180 | 1.0 | 35,070 | 35,209 | 28,745 | 39,154 | 1777 | 35,273 |

L10_W9 | 180 | 1.5 | 27,352 | 27,557 | 20,467 | 32,972 | 2364 | 27,610 |

L12_W7.5 | 90 | 0.5 | 42,396 | 42,438 | 40,587 | 43,739 | 556 | 42,418 |

L12_W7.5 | 90 | 1.0 | 38,010 | 38,108 | 34,226 | 40,998 | 1202 | 38,099 |

L12_W7.5 | 90 | 1.5 | 32,844 | 32,982 | 25,411 | 37,563 | 2047 | 33,017 |

L12_W7.5 | 180 | 0.5 | 40,336 | 40,403 | 37,131 | 42,602 | 946 | 40,432 |

L12_W7.5 | 180 | 1.0 | 32,633 | 32,865 | 24,711 | 37,868 | 2271 | 32,837 |

L12_W7.5 | 180 | 1.5 | 27,270 | 27,388 | 20,250 | 32,841 | 2293 | 27,610 |

L15_W6 | 90 | 0.5 | 43,003 | 43,035 | 41,594 | 44,107 | 448 | 43,060 |

L15_W6 | 90 | 1.0 | 39,647 | 39,715 | 36,613 | 41,875 | 915 | 39,698 |

L15_W6 | 90 | 1.5 | 35,756 | 35,837 | 30,559 | 39,342 | 1506 | 35,872 |

L15_W6 | 180 | 0.5 | 38,941 | 39,052 | 34,346 | 41,877 | 1224 | 39,051 |

L15_W6 | 180 | 1.0 | 28,550 | 28,787 | 21,321 | 34,182 | 2421 | 28,800 |

L15_W6 | 180 | 1.5 | 27,469 | 27,700 | 20,323 | 32,682 | 2355 | 27,610 |

L18_W5 | 90 | 0.5 | 43,447 | 43,470 | 42,238 | 44,396 | 370 | 43,483 |

L18_W5 | 90 | 1.0 | 40,677 | 40,738 | 38,233 | 42,544 | 743 | 40,729 |

L18_W5 | 90 | 1.5 | 37,590 | 37,654 | 33,897 | 40,379 | 1173 | 37,656 |

L18_W5 | 180 | 0.5 | 37,513 | 37,639 | 32,277 | 41,190 | 1498 | 37,620 |

L18_W5 | 180 | 1.0 | 28,509 | 28,653 | 21,226 | 34,121 | 2468 | 28,800 |

L18_W5 | 180 | 1.5 | 27,380 | 27,633 | 20,473 | 32,808 | 2362 | 27,610 |

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**MDPI and ACS Style**

Bellasio, R.; Bianconi, R.
A Heuristic Method for Modeling Odor Emissions from Open Roof Rectangular Tanks. *Atmosphere* **2022**, *13*, 367.
https://doi.org/10.3390/atmos13030367

**AMA Style**

Bellasio R, Bianconi R.
A Heuristic Method for Modeling Odor Emissions from Open Roof Rectangular Tanks. *Atmosphere*. 2022; 13(3):367.
https://doi.org/10.3390/atmos13030367

**Chicago/Turabian Style**

Bellasio, Roberto, and Roberto Bianconi.
2022. "A Heuristic Method for Modeling Odor Emissions from Open Roof Rectangular Tanks" *Atmosphere* 13, no. 3: 367.
https://doi.org/10.3390/atmos13030367