20.通用多相流模型(GeneralMultiphaseModels) 下载本文

在混合模型计算中定义第二相的步骤如下:

1. Select the phase (e.g., phase-2) in the Phase list.

2. Click Set..., and the Secondary Phase panel (Figure 20.6.6) will open.

Figure 20.6.6: The Secondary Phase Panel for the Mixture Model

3. In the Secondary Phase panel, enter a Name for the phase.

4. Specify which material the phase contains by choosing the appropriate material in the

Phase Material drop-down list. 5. Define the material properties for the Phase Material, following the same procedure you

used toset the material properties for the primary phase(see Section 20.6.8). For a particulate phase (which must be placed in the fluid materials category, as mentioned in Section 20.6.1), you need to specify only the density; you can ignore the values for the other properties, since they will not be used.

6. In the Secondary Phase panel, specify the Diameter of the bubbles, droplets, or particles

of this phase ( d p in Equation 20.3-12). You can specify a constant value, or use a user-defined function. See the separate UDF Manual for details about user-defined functions. 7. Click OK in the Secondary Phase panel.

Defining the Slip Velocity

如果你在混合计算中要求解滑流速度,你想指定滑流速度的定义,click Interaction... to

open the Phase Interaction panel (Figure 20.6.7).

Figure 20.6.7: The Phase Interaction Panel for the Mixture Model

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在Slip Velocity下面,你可以通过在附近下拉列表中选择合适的项目给与主相相关的第

二相指定滑流速度函数。

1. Select maninnen-et-al (the default) to use the algebraic slip method of Manninen et

al. [ 150], described in Section 20.3.4.

2. Select none if the secondary phase has the same velocity as the primary phase (i.e., no

slip velocity). 3. Select user-defined to use a user-defined function for the slip velocity. See the separate

UDF Manual for details. 20.6.10定义欧拉模型中的相(Defining Phases for the Eulerian Model)

在欧拉多相流计算中为主相和第二相指定必要的信息和它们的相互作用的说明由下面给出。

Defining the Primary Phase

在欧拉多相流计算中定义主相的步骤与在VOF计算中相同。详细内容见Section 20.6.8.

Defining a Non-Granular Secondary Phase

在欧拉多相流计算中定义非颗粒(即液体或气体)第二相的步骤如下: 1. Select the phase (e.g., phase-2) in the Phase list.

2. Click Set..., and the Secondary Phase panel (Figure 20.6.8) will open.

Figure 20.6.8: The Secondary Phase Panel for a Non-Granular Phase

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3. In the Secondary Phase panel, enter a Name for the phase.

4. Specify which material the phase contains by choosing the appropriate material in the

Phase Material drop-down list. 5. Define the material properties for the Phase Material, following the same procedure

you used to set the material properties for the primary phase (see Section 20.6.8). 6. In the Secondary Phase panel, specify the Diameter of the bubbles or droplets of this

phase.You can specify a constant value, or use a user-defined function. See the separate UDF Manual for details about user-defined functions.

7. Click OK in the Secondary Phase panel.

Defining a Granular Secondary Phase

在欧拉多相流计算中定义颗粒第二相的步骤如下: 1. Select the phase (e.g., phase-2) in the Phase list.

2. Click Set..., and the Secondary Phase panel (Figure 20.6.9) will open.

Figure 20.6.9: The Secondary Phase Panel for a Granular Phase

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3. In the Secondary Phase panel, enter a Name for the phase.

4. Specify which material the phase contains by choosing the appropriate material in the

Phase Material drop-down list. 5. Define the material properties for the Phase Material, following the same procedure

you usedgranular phase (which must be placed in the fluid ma to set the material properties for the primary phase (see Section 20.6.8). For a terials category, as mentioned in Section 20.6.1), you need to specify only the density; you can ignore the values for the other properties, since they will not be used.

6. In the Secondary Phase panel, specify the following properties of the particles of

this phase: Diameter

指定颗粒的直径。 You can select constant in the drop-down list and specify a constant value, or select user-defined to use a user-defined function. See the separate UDF Manual for details about user-defined functions. Granular Viscosity

指定颗粒的颗粒粘度的运动部分(?s,kinin Equation 20.4-50)。You can select constant (the default) in the drop-down list and specify a constant value, select yamlal-obrien to compute the value using Equation 20.4-52, select gidaspow to compute the value using Equation 20.4-53, or select user-defined to use a user-defined function. Granular Bulk Viscosity

specifies the solids bulk viscosity (?qin Equation 20.4-8). You can select constant

s

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