向下移动与 \underbrace 关联的文本

Question

有没有办法将与 相关的文本\underbrace{}向下移动？我试图在下面标记的图像中描述我的意思。文本“热传导”不需要包含在左括号和右括号中，也不需要包含在方括号中。目标是通过将文本移到括号外来降低实际方程的整体高度。

如果有帮助，这里是用于生成多孔介质中的热传输方程的原始乳胶（如下所示）：

\begin{equation*}
\underbrace{\left( 1+ \frac{1- \phi}{\theta} \frac{C_{P_{s}}}{C_{P_{w}}} \frac{\rho_s}{\rho_w} \right) \frac{\partial \left( \theta T \right) }{\partial t}}_\text{change in stored energy}=\frac{\partial }{\partial x_i} \left[ \theta \left( \underbrace{\frac {k_{T_{bulk}}}{\theta C_{P_{w}} \rho_w}}_{\text{Thermal} \atop \text{Conduction}} + \alpha \frac{\mathrm{q}}{\theta} \right) \cdot \frac{\partial T}{\partial x_j} \right] - \frac{\partial }{\partial x_i} \left( \theta v_i T \right) + q'_s T_s + \frac{\theta \gamma_w }{C_{p_{w}}} + \frac{ \left( 1 - \phi \right) \gamma_s }{C_{p_{w}}} \frac{\rho_s}{\rho_w}
\end{equation*}

Answer 1

如果您能够更新提供的原始 LaTeX 代码，则可以使用\biggl...对手动选择适当的分隔符高度\biggr：

\documentclass{article}

\usepackage{amsmath}

\begin{document}

\noindent Original equation:
\begin{equation*}
  \underbrace{
    \left(
      1 + \frac{1 - \phi}{\theta} \frac{C_{P_s}}{C_{P_w}} \frac{\rho_s}{\rho_w}
    \right)
    \frac{\partial \left( \theta T \right)}{\partial t}}_\text{change in stored energy}
    =
    \frac{\partial}{\partial x_i}
    \left[
      \theta
      \left(
        \underbrace{
          \frac{k_{T_{bulk}}}{\theta C_{P_w} \rho_w}
        }_{\text{Thermal} \atop \text{Conduction}}
        +
        \alpha \frac{\mathrm{q}}{\theta}
      \right) \cdot \frac{\partial T}{\partial x_j}
    \right]
    -
    \frac{\partial}{\partial x_i}
    \left(
      \theta v_i T
    \right)
    + q'_s T_s + \frac{\theta \gamma_w}{C_{P_w}} + \frac{\left( 1 - \phi \right) \gamma_s}{C_{P_w}} \frac{\rho_s}{\rho_w}
\end{equation*}

\noindent Modified equation:
\begin{equation*}
  \underbrace{
    \biggl(
      1 + \frac{1 - \phi}{\theta} \frac{C_{P_s}}{C_{P_w}} \frac{\rho_s}{\rho_w}
    \biggr)
    \frac{\partial ( \theta T )}{\partial t}}_\text{change in stored energy}
    =
    \frac{\partial}{\partial x_i}
    \biggl[
      \theta
      \biggl(
        \underbrace{
          \frac{k_{T_\text{bulk}}}{\theta C_{P_w} \rho_w}
        }_{\substack{\text{thermal} \\ \text{conduction}}}
        +
        \alpha \frac{\mathrm{q}}{\theta}
      \biggr) \cdot \frac{\partial T}{\partial x_j}
    \biggr]
    -
    \frac{\partial}{\partial x_i} (\theta v_i T)
    + q'_s T_s + \frac{\theta \gamma_w}{C_{P_w}} + \frac{(1 - \phi) \gamma_s}{C_{P_w}} \frac{\rho_s}{\rho_w}
\end{equation*}

\end{document}

其他细微变化包括：

• 删除不必要的\left...\right组合
• \text{bulk}
• \substack{\text{thermal} \\ \text{conduction}}
• 持续使用P_w