# 13.7.1: Pressure Loss Components

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In a tube flowing upward in incline angle $$\theta$$, the pressure loss is affected by friction loss, acceleration, and body force(gravitation). These losses are non-linear and depend on each other. For example, the gravitation pressure loss reduce the pressure and thus the density must change and hence, acceleration must occur. However, for small distances ($$dx$$) and some situations, this dependency can be neglected. In that case, from equation (25), the total pressure loss can be written as

Pressure Loss

$\label{phase:eq:dP} \dfrac{dP}{dx} = \overbrace{\left.\dfrac{dP}{dx} \right|_{f}}^{friction} + \overbrace{\left.\dfrac{dP}{dx} \right|_{a}}^{acceleration} + \overbrace{\left.\dfrac{dP}{dx} \right|_{g}}^{gravity}$

Every part of the total pressure loss will be discussed in the following section.