Convective heat transfer enhancement in solar air channels

Kumar, Anil; Kim, Man-Hoe

doi:10.1016/j.applthermaleng.2015.06.015

Cited by 58 publications

(21 citation statements)

References 106 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The RNG -ε model was therefore used in this study to simulate the heat transfer and fluid flow in the SAH channel. Similar methodology has been reported by various investigators [20,22,[24][25][26][27][28][29][30]. The results of the RNG k-ε model are in good agreement with the Dittus-Boelter empirical relation.…”

Section: Model Selection and Validationsupporting

confidence: 75%

“…The SAH collector's performance enhancement owing to the artificial roughness is usually estimated on the basis of the thermo-hydraulic performance parameter, which includes both the thermal and hydraulic concerns. The thermo-hydraulic performance parameter (Equation (7)) was defined as the overall enhancement ratio and expressed as follows [28][29][30]:…”

Section: Thermo-hydraulic Performancementioning

confidence: 99%

“…Some recent CFD studies [20][21][22][23][24][25][26][27][28][29][30] have also reported the enhancement in the thermal performance of solar air heaters by testing roughness geometries similar to those being employed for experimental investigations by many researchers in the past. These findings authenticate the usefulness of the experimental studies for the analysis of heat transfer and fluid flow behaviour of the artificially roughened SAHs.…”

Section: Introductionmentioning

confidence: 99%

“…Their simulation studies demonstrated that the RNG k-epsilon turbulence model was good agreement with experimental results. Kumar and Kim [27][28][29][30] conducted numerical investigations of thermal hydraulic performance improvement in various artificially roughened ducts using RNG k-epsilon turbulence model.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

CFD Analysis on the Thermal Hydraulic Performance of an SAH Duct with Multi V-Shape Roughened Ribs

Kumar

Kim

2016

Energies

Self Cite

View full text Add to dashboard Cite

This study presents the heat transfer and fluid flow characteristics in a rib-roughened SAH (solar air heater) channel. The artificial roughness of the rectangular channel was in the form of a thin circular wire in discrete multi V-pattern rib geometries. The effect of this geometry on heat transfer, fluid flow, and performance augmentation was investigated using the CFD (computational fluid dynamics). The roughness parameters were a relative discrete distance of 0.69, a relative rib height of 0.043, a relative rib pitch of 10, a relative rib width of 6.0, and a flow-attack-angle of 60˝. The discrete width ratios and Reynolds numbers ranged from 0.5 to 2.0 and from 2000 to 20,000, respectively. The CFD results using the renormalization k-epsilon model were in good agreement with the empirical relationship. This model was used to investigate the heat transfer and fluid flow characteristics in the multi V-pattern rib roughened SAH channel. The thermo-hydraulic performance was found to be the best for the discrete width ratio of 1.0. A discrete multi V-pattern rib combined with dimple staggered ribs also had better overall thermal performance compared to other rib shapes.

show abstract

Section: Model Selection and Validationsupporting

confidence: 75%

Section: Thermo-hydraulic Performancementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

CFD Analysis on the Thermal Hydraulic Performance of an SAH Duct with Multi V-Shape Roughened Ribs

Kumar

Kim

2016

Energies

Self Cite

View full text Add to dashboard Cite

show abstract

“…Solar energy is free, clean and most abundant energy resource among renewable energy resources. Solar energy originates from the sun and travels as radiations 1,2) . Energy storage provides a mean for improving the efficiency of a wide range of energy systems.…”

Section: Introductionmentioning

confidence: 99%

Mathematical Simulation on Thermal Performance of Packed Bed Solar Energy Storage System

Kumar¹,

Kim²

2015

Transactions of the Korean hydrogen and new energy society

Self Cite

View full text Add to dashboard Cite

>> Solar air heaters (SAHs) are simple in design and widely used for solar energy collection devices, and a packed bed is one of typical solar energy storage systems of thermal energy captured by SAHs. This paper presents mathematical modeling and simulation on the thermal performance of various packed bed energy storage systems. A MATLAB program is used to estimate the thermal efficiency of packed bed SAH. Among the various packed bed energy storage systems considered, the wire mesh screen packed bed SAH shows the best thermal efficiency over the entire range of design conditions. The maximum of thermal efficiency of packed bed SAH with wire mesh screen matrices has been found to be 0.794 for Re=2000 -20000 and ΔT/I=0.002 -0.02.

show abstract

Experimental analysis of evacuated tube solar air heater (ETSAH) with inbuilt sensible thermal energy storage

2022

View full text Add to dashboard Cite

In the present work, an evacuated tube solar air heater (ETSAH) with inbuilt sensible heat storage material (SHSM) is experimentally evaluated. The system comprises two sets each having 50 evacuated tubes with an H‐type arrangement and a total collector area of 16.92 m2. For the purpose of hot air generation, ETSAH is simultaneously connected in series and in parallel with and without the use of reflectors. Three different mass flow rates of 122.90, 164.87, and 212.83 kg/h were fixed to get 12 diverse cases of ETSAH operation. The highest hot air temperature reported by the system is 121.7°C when it was connected in series with conventional reflectors at 212.83 kg/h of flow rate and 469 W/m2 average solar intensity. The system reported an overall average energy efficiency of 49.76% and an exergy efficiency of 17.97% with the highest average hot air temperature difference of 56.12°C from 09:00 to 20:00 h. Without the incorporation of any additional SHSM, the average hot air temperature delivered by ETSAH (when under the neighbor building shadow) is 49.73°C logged from 17:00 to 20:00 h. The economic analysis is also carried out to ensure its practical application and feasibility. For the best system performance, the annual cost of hot air generation is 0.0194 Rs./kg (0.0002433 $/kg).

show abstract

Convective heat transfer enhancement in solar air channels

Cited by 58 publications

References 106 publications

CFD Analysis on the Thermal Hydraulic Performance of an SAH Duct with Multi V-Shape Roughened Ribs

CFD Analysis on the Thermal Hydraulic Performance of an SAH Duct with Multi V-Shape Roughened Ribs

Mathematical Simulation on Thermal Performance of Packed Bed Solar Energy Storage System

Experimental analysis of evacuated tube solar air heater (ETSAH) with inbuilt sensible thermal energy storage

Contact Info

Product

Resources

About