# Numerical investigation on the bifurcative natural convection in a horizontal concentric annulus

## Abstract

Natural convective heat transfer in an annulus bounded by two horizontal cylinders has attracted intensive attention in research because of its wide technological applications, such as solar energy storage, ducting systems, and underground cable systems. Here, steady state two-dimensional natural convective heat transfer in a horizontal cylindrical annulus was studied by solving the governing equations based on the primitive variables. Emphasis was put on the occurrence of multiple solutions and on the determination of the bifurcation points at which those multiple solutions begin to branch out. The multicellular flow patterns from the results of melting processes in an isothermally heated horizontal cylinder for high Rayleigh numbers were used as initial fields. This approach succeeded in finding new bifurcation points to a tetracellular solution for a set of parameter variables identical to those used in previous studies. Close examination of flow pattern transitions near the bifurcation point was also conducted. It was found that the mechanisms of flow transition are different depending on the critical Rayleigh number of the bifurcation point.

- Authors:

- Seoul National Univ. (Korea, Republic of)
- Soongsil Univ., Seoul (Korea, Republic of). Dept. of Mechanical Engineering

- Publication Date:

- OSTI Identifier:
- 687495

- Resource Type:
- Journal Article

- Journal Name:
- Numerical Heat Transfer. Part A, Applications

- Additional Journal Information:
- Journal Volume: 36; Journal Issue: 3; Other Information: PBD: 27 Aug 1999

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; NUMERICAL ANALYSIS; NATURAL CONVECTION; ANNULAR SPACE; TWO-DIMENSIONAL CALCULATIONS; BIFURCATION

### Citation Formats

```
Chung, J.D., Kim, C.J., Lee, J.S., and Yoo, H.
```*Numerical investigation on the bifurcative natural convection in a horizontal concentric annulus*. United States: N. p., 1999.
Web.

```
Chung, J.D., Kim, C.J., Lee, J.S., & Yoo, H.
```*Numerical investigation on the bifurcative natural convection in a horizontal concentric annulus*. United States.

```
Chung, J.D., Kim, C.J., Lee, J.S., and Yoo, H. Fri .
"Numerical investigation on the bifurcative natural convection in a horizontal concentric annulus". United States.
```

```
@article{osti_687495,
```

title = {Numerical investigation on the bifurcative natural convection in a horizontal concentric annulus},

author = {Chung, J.D. and Kim, C.J. and Lee, J.S. and Yoo, H.},

abstractNote = {Natural convective heat transfer in an annulus bounded by two horizontal cylinders has attracted intensive attention in research because of its wide technological applications, such as solar energy storage, ducting systems, and underground cable systems. Here, steady state two-dimensional natural convective heat transfer in a horizontal cylindrical annulus was studied by solving the governing equations based on the primitive variables. Emphasis was put on the occurrence of multiple solutions and on the determination of the bifurcation points at which those multiple solutions begin to branch out. The multicellular flow patterns from the results of melting processes in an isothermally heated horizontal cylinder for high Rayleigh numbers were used as initial fields. This approach succeeded in finding new bifurcation points to a tetracellular solution for a set of parameter variables identical to those used in previous studies. Close examination of flow pattern transitions near the bifurcation point was also conducted. It was found that the mechanisms of flow transition are different depending on the critical Rayleigh number of the bifurcation point.},

doi = {},

journal = {Numerical Heat Transfer. Part A, Applications},

number = 3,

volume = 36,

place = {United States},

year = {1999},

month = {8}

}