Thermal analysis of a triple helix ground heat exchanger using numerical simulation and multiple linear regression

In the present study, the effect of utilizing two different types of baffles in the channel of the solar air heater is investigated numerically. The studied baffles include angled rectangular baffles and angled V-shaped baffles, which are mounted on the bottom and top walls of the duct, respectively. Both considered baffles were evaluated separately which the studied parameter in each section was the angular position of baffles. Finally, the best-obtained results of both sections were compared to each other. The results indicated that in the rectangular model by comparison between 90°model and no baffle, it was found that the pressure drop and average Nusselt number increase 316.67% and 148.15%, respectively at Reynolds number (Re) = 2000. Also, in V-shaped angled baffles, the thermal efficiency of β = 90°, 60°, 45°, and 30°are 27%, 18%, 13% higher than no baffle channel at Re = 2000, respectively. Furthermore, at low Re (about Re below 300), utilizing baffles into the channel had no effect on the thermal efficiency of the system compared to the no baffle channel. However, at high Re, it was found that the highest thermal efficiency occurred in the model of rectangular baffles with an angle of 90°. K E Y W O R D S baffle, heat-transfer enhancement, numerical simulation, solar air heater

show abstract

“…The Friction factor, f , defined as 44 :

f = \frac{2 {normald}_{normalh} Δ P}{ρ {normalu}^{2} B},

where d h and Δ P is hydraulic diameter, pressure drop, respectively. The thermal efficiency of collector is defined by following equation 63‐70 :

η = true(\frac{Nu}{italicN u_{0}} true) {(\frac{f_{0}}{italicf})}^{\frac{1}{3}} .

where Nu 0 and f 0 are defined as Nu and friction factor of the simple channel of the solar air heater without baffles.…”

Section: Mathematical Formulationmentioning

confidence: 99%

Numerical evaluation of the thermal performance of a solar air heater equipped with two different types of baffles

2020

View full text Add to dashboard Cite

show abstract

“…The results also presented that a significant effect of hot water inlet temperature on the Nusselt number while the increase in pressure drop can be approximately considered neglect. Hossein Javadi et al [3] geothermal heat exchangers, one of the main components of shallow geothermal systems, have been investigated by many researchers in recent years to exploit clean and renewable energies. Most of the previous studies have mostly concentrated on the common types of ground heat exchangers including U-tube and helical ground heat exchangers.…”

Section: Literature Reviewmentioning

confidence: 99%

A Review on Triple Tube Heat Exchanger on Optimizing Thermal Efficiency

Suryakant¹,

Vishwakarma²,

Mishra³

2020

IJOSCIENCE

View full text Add to dashboard Cite

Over the past few decades, technological developments have faced challenges in meeting cooling needs. Further work is underway on optimal heat transfer in concentric heat exchangers; one of the double tube heat exchangers examined is the triple tube heat exchanger (TTHE). Three-pipe heat exchangers were found to be more efficient than two-pipe heat exchangers. This review presented is the working principle of the triple concentric tube heat exchanger and the proposed methodology is used in a computational fluid dynamics algorithm.

show abstract

“…There have been many studies focusing on various methods to enhance the performance of BHEs [2,[15][16][17][18][19][20]. Pure water is reported to be the most commonly applied working fluid in the BHEs [2]; nevertheless, nanofluids' applications in the BHEs as working fluid has recently been under evaluation.…”

Section: Introductionmentioning

confidence: 99%

Impact of Employing Hybrid Nanofluids as Heat Carrier Fluid on the Thermal Performance of a Borehole Heat Exchanger

et al. 2021

Self Cite

View full text Add to dashboard Cite

In this numerical study, 4 types of hybrid nanofluid, including Ag-MgO/water, TiO2-Cu/water, Al2O3-CuO/water, and Fe3O4-multi-wall carbon nanotube/water, have been considered potential working fluid in a single U-tube borehole heat exchanger. The selected hybrid nanofluid is then analyzed by changing the volume fraction and the Reynolds number. Based on the numerical results, Ag-MgO/water hybrid nanofluid is chosen as the most favorable heat carrier fluid, among others, considering its superior effectiveness, minor pressure drop, and appropriate thermal resistance compared to the pure water. Moreover, it was indicated that all cases of Ag-MgO/water hybrid nanofluid at various volume fractions (from 0.05 to 0.20) and Reynolds numbers (from 3200 to 6200) could achieve better effectiveness and lower thermal resistances, but higher pressure drops compared to the corresponding cases of pure water. Nevertheless, all the evaluated hybrid nanofluids present lower coefficient of performance (COP)-improvement than unity which means that applying them as working fluid is not economically viable because of having higher pressure drop than the heat transfer enhancement.

show abstract

Thermal analysis of a triple helix ground heat exchanger using numerical simulation and multiple linear regression

Cited by 36 publications

References 57 publications

Numerical evaluation of the thermal performance of a solar air heater equipped with two different types of baffles

Numerical evaluation of the thermal performance of a solar air heater equipped with two different types of baffles

A Review on Triple Tube Heat Exchanger on Optimizing Thermal Efficiency

Impact of Employing Hybrid Nanofluids as Heat Carrier Fluid on the Thermal Performance of a Borehole Heat Exchanger

Contact Info

Product

Resources

About