CHE-40

Dittus–Boelter Nu

Turbulent pipe Nusselt.

Reading speed

GoverningDittus–Boelter Nu

Governing equation

Nu=0.023 Re^{0.8} Pr^{n}

where

Re: Re (—)
Pr: Pr (—)
n: n (—)
Nu: Dittus–Boelter Nu (—)

Lecture brief

Historical brief

From CSTR/PFR mole balances and Arrhenius rates to McCabe–Thiele stages and NTU exchangers, chemical engineering is conservation plus equilibrium. The lab is that design arithmetic. This sheet (CHE-40 — Dittus–Boelter Nu) is the form associated with Dittus–Boelter Nu. Working symbols: $Re$ , $Pr$ , $n$ $\rightarrow$ $Nu$ . Turbulent pipe Nusselt. Pedagogical SI sheet with a live model and a swept parameter.

Purpose

Purpose: compute

Nu

from

Re

Pr

n

in Chemical engineering via

Nu=0.023 Re^{0.8} Pr^{n}

Turbulent pipe Nusselt. Use it when a real chemical engineering question must be answered in SI before a code check.

Live realistic example

In symbols

Live case. Given

Re = 20000.000\,\mathrm{—}

Pr = 7.000\,\mathrm{—}

n = 0.400\,\mathrm{—}

, the governing relation

Nu=0.023 Re^{0.8} Pr^{n}

yields

Nu = 138.226\,\mathrm{—}

. One governing identity, SI units, a single sweep on the sheet. Move a slider: the numbers are this situation, not a canned story.

Calculator

Inputs

Re Re20000 —Pr Pr7 —n n0.4 —

Outputs

Dittus–Boelter Nu Nu138.226 —

Reading speed

Watch on YouTube

Free library

Full library

Free PDF / open book

YouTube channels

00:0 / 00:08

Narration of this film

One governing identity, SI units, a single sweep on the sheet.

Turbulent pipe Nusselt. Pedagogical SI sheet with a live model and a swept parameter.

Reading speed

Watch on YouTube