High Rotation Number Effects on Heat Transfer in a Rectangular (AR=2:1) Two Pass Channel

Huh, Michael; Lei, Jiang; Liu, Yao-Hsien; Han, Je-Chin

doi:10.1115/gt2009-59421

Cited by 11 publications

(15 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The most interesting result is that on the contrary than in previous works (9,19) , the heat transfer efficiency drops, in the ribbed trailing wall (Rib-TR) case, compared with the stationary case. This behaviour is consistent, both in the experiments and in the numerical simulations.…”

Section: Segment Averaged Heat Transfer Validationmentioning

confidence: 71%

See 1 more Smart Citation

Numerical study of uneven wall-heating effect for a one side rib-roughened cooling channel subject to rotation

Wang

Corral²

2018

Aeronaut. j.

View full text Add to dashboard Cite

This paper investigates the impact of the wall-heating conditions on the heat transfer performance of a rotating channel with one side smooth and one side roughened by 45° inclined ribs. Previous experimental and numerical studies for single-ribbed wall-heated channels showed that rotation has a significant negative impact on heat transfer performance. In order to investigate this uncommon behaviour, RANS simulations were conducted under three different wall-heating conditions in the present study: ribbed wall heated, all walls heated and adiabatic conditions. Numerical results show that the presence of uneven wall-heating conditions has a negligible impact on the stationary case, but it has a large influence on rotational cases, in both, the heat transfer and the flow field. The underlying reason is that in rotating cases, uneven heating results in different buoyancy effects on the trailing and leading walls of the channel that alter the main flow velocity profile. As a consequence, also secondary flows and heat transfer performance are affected.

show abstract

Section: Segment Averaged Heat Transfer Validationmentioning

confidence: 71%

“…Previous studies (9,22) have shown that the entry shape can have a significant impact on the flowfield and heat transfer performance. Therefore, the computational domain was extended to include the supply system in order to account for inlet entry effects.…”

Section: Numerical Set-upmentioning

confidence: 99%

Numerical study of uneven wall-heating effect for a one side rib-roughened cooling channel subject to rotation

Wang

Corral²

2018

Aeronaut. j.

View full text Add to dashboard Cite

show abstract

“…The buoyancy number (Buo) is always employed to quantify the strength of buoyancy force. In this study, Huh et al's 29 method was followed to study the effect of buoyancy number. According to the definition of Buo…”

Section: The Effect Of Buoyancy Numbermentioning

confidence: 99%

Two-dimensional heat transfer distribution in a rotating smooth rectangular channel with four surface heating boundary condition

You

Wei

et al. 2017

Advances in Mechanical Engineering

View full text Add to dashboard Cite

In this study, two-dimensional heat transfer distribution on the leading surface and trailing surface in a rotating smooth channel with typical boundary condition of four surface heating was investigated experimentally for the first time. The Reynolds number, based on channel hydraulic diameter (80 mm) and the bulk mean velocity, ranges from 15,000 to 30,000, and the highest rotation number is 0.359 with the Reynolds number of 15,000. The mean density ratio is about 0.11 in this work. The obtained result showed that rotation has an important effect on the heat transfer distribution along the span-wise direction. On the leading side, rotation-induced secondary flow makes the Nu/Nu 0 at the edge area of the wall surface (Z/D = 0 and Z/D = 1) is higher than that on the middle area (Z/D = 0.5). On the trailing surface, the trend of Nu/Nu 0 ratio along the span-wise direction is reversed. Along the stream-wise direction, the Nu/Nu s ratio increases with the rotation number monotonously on the trailing side. However, on the leading side, with the increase in rotation number, the Nu/Nu s does not decrease monotonously along the stream-wise direction, there is a slight enhancement along the stream-wise direction. The secondary flow induced by rotation enhances Nu=Nu s ratio up to 1.35 on the trailing side and weakens the Nu=Nu s ratio close to 0.75 on the leading side with the Re = 15,000, and Ro = 0.359. More details of two-dimensional distribution of temperature and Nu on the leading and trailing side are shown in this work.

show abstract

“…Previous studies (Wright et al, 2005a;Huh et al, 2011) have shown that, the entry shape can have a significant impact on the flow-field and heat transfer performance. Therefore, the computational domain was extended to include the supply system in order to account for inlet entry effects.…”

Section: Numerical Set-upmentioning

confidence: 99%

Numerical Study of Effect of Wall Heating Conditions on Heat Transfer Performance of Rotating Internal Cooling Channels

Wang

Corral

2017

European Conference on Turbomachinery Fluid Dynamics and Hermodynamics

View full text Add to dashboard Cite

This paper investigates the impacts of wall heating conditions on heat transfer performace for a rotating channel with one side smooth and one side roughened by 45 degree inclined ribs. Previous experimental and numerical studies for only ribbed wall heated case showed that rotation has significantly negative impact on heat transfer performance. In order to investigate this uncommon behaviour, RANS simulations were conducted under three different wall heating conditions in present study: ribbed wall heated, all walls heated and adiabatic conditions. Numerical results show that the uneven wall heating condtions has negligible impact on stationary case, however, it has a large influence on rotational cases, in both the heat transfer and the fluid field. This is because in rotating cases, uneven heatings result in different buoyancy effects on trailing and leading walls that alter the main flow velocity profile. As a consequence, also secondary flows and heat transfer performance are affected. NOMENCLATURE AR Aspect ratio P r Prandtl number Bo Buoyancy number Re Reynolds number d h hydraulic diameter Ro Rotational number e rib height T ref Reference temperature e/d h blockage ratio T w wall temperature N u Nusselt Number N u 0 Dittus-Boelter correlation (heating) U 0 Inlet mean velocity U x Stream-wise velocity U y Span-wise velocity

show abstract

High Rotation Number Effects on Heat Transfer in a Rectangular (AR=2:1) Two Pass Channel

Cited by 11 publications

References 0 publications

Numerical study of uneven wall-heating effect for a one side rib-roughened cooling channel subject to rotation

Numerical study of uneven wall-heating effect for a one side rib-roughened cooling channel subject to rotation

Two-dimensional heat transfer distribution in a rotating smooth rectangular channel with four surface heating boundary condition

Numerical Study of Effect of Wall Heating Conditions on Heat Transfer Performance of Rotating Internal Cooling Channels

Contact Info

Product

Resources

About