VMFL067

VMFL067
Boiling in a Pipe-Critical Heat Flux

Overview

Reference

N. Hoyer, “Calculation of dryout and post-dryout heat transfer for tube geometry”, International Journal of Multiphase Flow, Vol 24, pp. 319-334, 1998

Solver Ansys Fluent

Physics/Models

Multiphase, heat and mass transfer, boiling

Input File

VMFL067_FLUENT.cas for Ansys Fluent

Project Files Link to Project Files Download Page

Test Case

This test case considers boiling near a heated wall of a vertical pipe. The effects of critical heat flux and post-dryout heat transfer are modeled in a vertical circular pipe. The outer wall of the pipe is heated with a constant heat flux.

Figure 159: Flow Domain

Material Properties	Geometry	Boundary Conditions
Steam-Water 2-phase Flow: Water: continuous phase Water Steam: dispersed bubbles	Radius of the pipe = 5 mm Height of the pipe = 7 m	Mass flux at inlet = 1495 kg/m²/s Heat transfer at the wall = 797000 W/m²

Material Properties

Geometry

Boundary Conditions

Steam-Water 2-phase Flow:

Water: continuous phase
Water Steam: dispersed bubbles

Radius of the pipe = 5 mm

Height of the pipe = 7 m

Mass flux at inlet =

1495 kg/m²/s

Heat transfer at the wall =

797000 W/m²

Analysis Assumptions and Modeling Notes

The flow is steady. RNG k-epsilon model is used for turbulence.

Results Comparison for Ansys Fluent

Figure 160: Comparison of Wall Temperature