Subtopic: Convective heat transfer coefficient from Nusselt number
Question Statement:
Liquid milk flows inside a tubular pasteurizer tube of internal diameter $D = 50\text{ mm}$. The thermal conductivity of milk is $k = 0.60\text{ W/(m}\,\text{K)}$. If the flow conditions give a Nusselt number $Nu = 160$, the convective heat transfer coefficient $h$ is ________ $\text{W/(m}^2\,\text{K)}$ (round off to one decimal place).
Answer Key:
1920.0
Step-by-Step Solution & Explanation
From the definition of Nusselt number:
$Nu = \frac{h D}{k} \implies h = \frac{Nu \cdot k}{D}$
Given $Nu = 160$, $k = 0.60\text{ W/(m K)}$, and $D = 0.05\text{ m}$:
$h = \frac{160 \times 0.60}{0.05} = 1920.0\text{ W/(m}^2\text{ K)}$