# How do you find the Nusselt number of a laminar flow?

## How do you find the Nusselt number of a laminar flow?

Calculation of the Nusselt number using Dittus-Boelter equation+

1. the Reynolds number, which is ReDh = 575600.
2. the Prandtl number, which is Pr = 0.89.

What is the formula of Nusselt number?

the Nusselt number, which is NuDh = 890. the hydraulic diameter of the fuel channel is: Dh = 13,85 mm. the thermal conductivity of reactor coolant (300°C) is: kH2O = 0.545 W/m.K. the bulk temperature of reactor coolant at this axial coordinate is: Tbulk = 296°C.

Is Nusselt number constant for laminar flow?

The Nusselt number in the fully developed laminar flow is constant and depends on the channel geometry and the wall heat transfer boundary condition.

### What is the Reynolds number for laminar flow?

Internal Flow

Flow type Reynolds Number Range
Laminar regime up to Re=2300
Transition regime 2300
Turbulent regime Re>4000

What does Prandtl number tell us?

Prandtl number signifies the thickness of thermal boundary layer and thickness of hydrodyanamic boundary layer, depending on whether it is equal to one, or more than one or less than one. Tells us the relative thickness of thermal boundary layer to momentum boundary layer.

Where do we use Nusselt number?

Nusselt number on the other hand is a non-dimensional heat transfer coefficient. It is used to determine whether the heat transfer is conduction or convection.

#### Can Nusselt number be less than 1?

Nu can not be less than one since it gives relation between conduction and convection of the liquid.

Why Nusselt number is used?

How do you use Reynolds number?

The Reynolds number is used to study fluids as they flow. The Reynolds number determines whether a fluid flow is laminar or turbulent. Flowing fluids normally follow along streamlines. If a flow is laminar, fluids will move along smooth streamlines.