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

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.

Download Full-text

Investigation of Counterflow Microchannel Heat Exchanger with Hybrid Nanoparticles and PCM Suspension as a Coolant

Mathematical Problems in Engineering ◽

10.1155/2021/6687064 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Mushtaq I. Hasan ◽

Mohammad J. Khafeef ◽

Omid Mohammadi ◽

Suvanjan Bhattacharyya ◽

Alibek Issakhov

Keyword(s):

Thermal Conductivity ◽

Heat Exchanger ◽

Pressure Drop ◽

Pure Water ◽

Thermal Characteristics ◽

Hybrid Nanoparticles ◽

Working Fluid ◽

Microchannel Heat Exchanger ◽

Noticeable Increase ◽

Nanoparticles Concentration

The effect of the hybrid suspension on the intrinsic characteristics of microencapsulated phase change material (MEPCM) slurry used as a coolant in counterflow microchannel heat exchanger (CFMCHE) with different velocities is investigated numerically. The working fluid used in this paper is a hybrid suspension consisting of nanoparticles and MEPCM particles, in which the particles are suspended in pure water as a base fluid. Two types of hybrid suspension are used (Al2O3 + MEPCM and Cu + MEPCM), and the hydrodynamic and thermal characteristics of these suspensions flowing in a CFMCHE are numerically investigated. The results indicated that using hybrid suspension with high flow velocities improves the performance of the microchannel heat exchanger while resulting in a noticeable increase in pressure drop. Thereupon, it causes a decrease in the performance index. Moreover, it was found that the increment of the nanoparticles’ concentration can rise the low thermal conductivity of the MEPCM slurry, but it also leads to a noticeable increase in pressure drop. Furthermore, it was found that as the thermal conductivity of Cu is higher than that for Al2O3, the enhancement in heat transfer is higher in case of adding Cu particles compared with Al2O3 particles. Therefore, the effectiveness of these materials depends strongly on the application at which CFMCHE is employed.

Download Full-text

Thermodynamic analysis of hybrid nanofluid based solar flat plate collector

World Journal of Engineering ◽

10.1108/wje-03-2017-0048 ◽

2018 ◽

Vol 15 (1) ◽

pp. 27-39

Author(s):

Ranga Babu J.A. ◽

Kiran Kumar K. ◽

Srinivasa Rao S.

Keyword(s):

Pressure Drop ◽

Flat Plate ◽

Hybrid Nanoparticles ◽

Working Fluid ◽

Hybrid Nanofluid ◽

Heat Gain ◽

Content Type ◽

Energy And Exergy ◽

Hybrid Nanofluids ◽

Flat Plate Collector

Purpose This paper aims to present an analytical investigation of energy and exergy performance on a solar flat plate collector (SFPC) with Cu-CuO/water hybrid nanofluid, Cu/water and CuO/water nanofluids as collector running fluids. Design/methodology/approach Heat transfer characteristics, pressure drop and energy and exergy efficiencies of SFPC working on these nanofluids are investigated and compared. In this study, a comparison is made by varying the mass flow rates and nanoparticle volume concentration. Thermophysical properties of hybrid nanofluids are estimated using distinctive correlations available in the open literature. Then, the influence of these properties on energy and exergy efficiencies of SFPC is discussed in detail. Findings Energy analysis reveals that by introducing the hybrid nanoparticles in water, the thermal conductivity of the working fluid is enhanced by 17.52 per cent and that of the individual constituents is enhanced by 15.72 and 15.35 per cent for Cu/water and CuO/water nanofluids, respectively. This resulted in 2.16 per cent improvement in useful heat gain for hybrid nanofluid and 1.03 and 0.91 per cent improvement in heat gain for Cu/water and CuO/water nanofluids, respectively. In line with the above, the collector efficiency increased by 2.175 per cent for the hybrid nanofluid and 0.93 and 1.05 per cent enhancement for Cu/water and CuO/water nanofluids, respectively. Exergy analysis elucidates that by using the hybrid nanofluid, exergy efficiency is increased by 2.59 per cent, whereas it is 2.32 and 2.18 per cent enhancement for Cu/water and CuO/water nanofluids, respectively. Entropy generation is reduced by 3.31, 2.35 and 2.96 per cent for Cu-CuO/water, Cu/water and CuO/water nanofluids, respectively, as compared to water. Research limitations/implications However, this is associated with a penalty of increment in pressure drop of 2.92, 3.09 and 2.74 per cent for Cu-CuO/water, Cu/water and CuO/water nanofluids, respectively, compared with water. Originality/value It is clear from the analysis that Cu-CuO/water hybrid nanofluids possess notable increment in both energy and exergy efficiencies to use them in SFPCs.

Download Full-text

Simulation approach on turbulent thermal performance factor of Al2O3-Cu/water hybrid nanofluid in circular and non-circular ducts

SN Applied Sciences ◽

10.1007/s42452-021-04317-w ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Ing Jiat Kendrick Wong ◽

Ngieng Tze Angnes Tiong

Keyword(s):

Heat Transfer ◽

Reynolds Number ◽

Pressure Drop ◽

Thermal Performance ◽

Heat Transfer Performance ◽

Pure Water ◽

Hybrid Nanofluid ◽

Performance Factor ◽

Thermal Performance Factor ◽

The Heat Transfer Coefficient

AbstractThis paper presents the numerical study of thermal performance factor of Al2O3-Cu/water hybrid nanofluid in circular and non-circular ducts (square and rectangular). Turbulent regime is studied with the Reynolds number ranges from 10000 to 100000. The heat transfer performance and flow behaviour of hybrid nanofluid are investigated, considering the nanofluid volume concentration between 0.1 and 2%. The thermal performance factor of hybrid nanofluid is evaluated in terms of performance evaluation criteria (PEC). This present numerical results are successfully validated with the data from the literature. The results indicate that the heat transfer coefficient and Nusselt number of Al2O3-Cu/water hybrid nanofluid are higher than those of Al2O3/water nanofluid and pure water. However, this heat transfer enhancement is achieved at the expense of an increased pressure drop. The heat transfer coefficient of 2% hybrid nanofluid is approximately 58.6% larger than the value of pure water at the Reynolds number of 10000. For the same concentration and Reynolds number, the pressure drop of hybrid nanofluid is 4.79 times higher than the pressure drop of water. The heat transfer performance is the best in the circular pipe compared to the non-circular ducts, but its pressure drop increment is also the largest. The hybrid nanofluid helps to improve the problem of low heat transfer characteristic in the non-circular ducts. In overall, the hybrid nanofluid flow in circular and non-circular ducts are reported to possess better thermal performance factor than that of water. The maximum attainable PEC is obtained by 2% hybrid nanofluid in the square duct at the Reynolds Number of 60000. This study can help to determine which geometry is efficient for the heat transfer application of hybrid nanofluid.

Download Full-text

Experimental Investigation on Stability, Viscosity, and Electrical Conductivity of Water-Based Hybrid Nanofluid of MWCNT-Fe2O3

Nanomaterials ◽

10.3390/nano11010136 ◽

2021 ◽

Vol 11 (1) ◽

pp. 136

Author(s):

Solomon O. Giwa ◽

Mohsen Sharifpur ◽

Mohammad H. Ahmadi ◽

S. M. Sohel Murshed ◽

Josua P. Meyer

Keyword(s):

Electrical Conductivity ◽

Visual Inspection ◽

Volume Concentration ◽

Working Fluid ◽

Hybrid Nanofluid ◽

Multiwalled Carbon ◽

Transmission Electron ◽

Hybrid Nanofluids ◽

Uv Visible ◽

The Stability

The superiority of nanofluid over conventional working fluid has been well researched and proven. Newest on the horizon is the hybrid nanofluid currently being examined due to its improved thermal properties. This paper examined the viscosity and electrical conductivity of deionized water (DIW)-based multiwalled carbon nanotube (MWCNT)-Fe2O3 (20:80) nanofluids at temperatures and volume concentrations ranging from 15 °C to 55 °C and 0.1–1.5%, respectively. The morphology of the suspended hybrid nanofluids was characterized using a transmission electron microscope, and the stability was monitored using visual inspection, UV–visible, and viscosity-checking techniques. With the aid of a viscometer and electrical conductivity meter, the viscosity and electrical conductivity of the hybrid nanofluids were determined, respectively. The MWCNT-Fe2O3/DIW nanofluids were found to be stable and well suspended. Both the electrical conductivity and viscosity of the hybrid nanofluids were augmented with respect to increasing volume concentration. In contrast, the temperature rise was noticed to diminish the viscosity of the nanofluids, but it enhanced electrical conductivity. Maximum increments of 35.7% and 1676.4% were obtained for the viscosity and electrical conductivity of the hybrid nanofluids, respectively, when compared with the base fluid. The obtained results were observed to agree with previous studies in the literature. After fitting the obtained experimental data, high accuracy was achieved with the formulated correlations for estimating the electrical conductivity and viscosity. The examined hybrid nanofluid was noticed to possess a lesser viscosity in comparison with the mono-particle nanofluid of Fe2O3/water, which was good for engineering applications as the pumping power would be reduced.

Download Full-text

Augmentation of the Heat Transfer Performance of a Sinusoidal Corrugated Enclosure by Employing Hybrid Nanofluid

Advances in Mechanical Engineering ◽

10.1155/2014/147059 ◽

2014 ◽

Vol 6 ◽

pp. 147059 ◽

Cited By ~ 78

Author(s):

Behrouz Takabi ◽

Saeed Salehi

Keyword(s):

Heat Transfer ◽

Heat Transfer Performance ◽

Heated Surface ◽

Pure Water ◽

Maximum Error ◽

Temperature Fields ◽

Working Fluid ◽

Hybrid Nanofluid ◽

Transfer Performance ◽

Lower Temperature

This paper numerically examines laminar natural convection in a sinusoidal corrugated enclosure with a discrete heat source on the bottom wall, filled by pure water, Al2O3/water nanofluid, and Al2O3-Cu/water hybrid nanofluid which is a new advanced nanofluid with two kinds of nanoparticle materials. The effects of Rayleigh number (103≤Ra≤106) and water, nanofluid, and hybrid nanofluid (in volume concentration of 0% ≤ ϕ ≤ 2%) as the working fluid on temperature fields and heat transfer performance of the enclosure are investigated. The finite volume discretization method is employed to solve the set of governing equations. The results indicate that for all Rayleigh numbers been studied, employing hybrid nanofluid improves the heat transfer rate compared to nanofluid and water, which results in a better cooling performance of the enclosure and lower temperature of the heated surface. The rate of this enhancement is considerably more at higher values of Ra and volume concentrations. Furthermore, by applying the modeling results, two correlations are developed to estimate the average Nusselt number. The results reveal that the modeling data are in very good agreement with the predicted data. The maximum error for nanofluid and hybrid nanofluid was around 11% and 12%, respectively.

Download Full-text

FIBERGLASS CIRCULAR TURBULATOR IN COUNTER FLOW DOUBLE PIPE HEAT EXCHANGER: A STUDY OF HEAT TRANSFER RATE AND PRESSURE DROP

SINERGI ◽

10.22441/sinergi.2021.1.007 ◽

2020 ◽

Vol 25 (1) ◽

pp. 51

Author(s):

Sudiono Sudiono ◽

Rita Sundari ◽

Rini Anggraini

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Pressure Drop ◽

Heat Transfer Rate ◽

Transfer Rate ◽

Preliminary Investigation ◽

Working Fluid ◽

Geometrical Shape ◽

Double Pipe ◽

Pipe Heat

This preliminary investigation studied the effect of circular turbulator vortex generator on heat transfer rate and pressure drop in a circular channel countercurrent double pipe heat exchanger with water working fluid. Increasing the number of circular turbulator yielded increasing heat transfer rate and pressure drop. The problem generated when increased pressure drop occurred in relation to more energy consumption of the water pumping system. Therefore, optimization in circular turbulator number is necessary to minimize the pressure drop about distance length between circular turbulator, tube diameter and thickness, type of material and crystal lattice, as well as the geometrical shape of fluid passage (circular or square). This study applied PVC outer tube and copper alloy inner tube, as well as fiberglass circular turbulator. The optimum results showed that seven parts of circular turbulator increasing heat transfer rate by 30% and pressure drop by 80% compared to that passage in the absence of circular turbulator at cool water debit of 7 L/min.

Download Full-text

Investigation on Shell-Side Performance of Heat Exchanger With Axially Staggered Overlap Helical Baffles

2010 14th International Heat Transfer Conference, Volume 4 ◽

10.1115/ihtc14-22250 ◽

2010 ◽

Author(s):

Shui Ji ◽

Wenjing Du ◽

Lin Cheng

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Heat Exchanger ◽

Pressure Drop ◽

Transfer Coefficient ◽

Low Cost ◽

Convection Heat Transfer ◽

Working Fluid ◽

Shell Side ◽

Open Issue

Since its appearance in the 80’s of the 20th century, the heat exchanger with helical baffles (HEHBs) has attracted lots of attention. Benefiting from its relatively simple manufacture procedure and low cost, the heat exchanger with overlapped helical baffles receives much concern. However, there are few reports on the influence of the specific overlap size of helical baffles on the shell-side heat transfer performance and fluid friction property. In this paper, numerical investigation on this open issue is carried out by means of numerical method. The emphasis is laid on the relationship between the overlap size of helical baffles and the shell-side performance. Baffles with the shape of a quarter-ellipse are simulated and the heat-transfer oil is selected as the working fluid. Results show that in the condition of same helix angles and same flow rates, 10% increase of the specific overlap size brings an increase of 23–42% on the pressure drop and an increase of 2–8% on the convection heat transfer coefficient; hence the corresponding heat transfer coefficient pre unit pressure drop is decreased by 11–22%. Compared with the continuously overlap configuration, the axially staggered overlap helical baffles can improve the comprehensive performance of HEHBs on the condition of an identical helical pitch, and hence it is favorable for the situation with strict constrain on pressure drop.

Download Full-text

Heat Transfer Enhancement in Microchannel Flow: Presence of Microparticles in a Fluid

ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels: Parts A and B ◽

10.1115/fedsm-icnmm2010-30921 ◽

2010 ◽

Cited By ~ 5

Author(s):

Awad B. S. Alquaity ◽

Salem A. Al-Dini ◽

Evelyn N. Wang ◽

Shahzada Z. Shuja ◽

Bekir S. Yilbas ◽

...

Keyword(s):

Heat Transfer ◽

Temperature Distribution ◽

Pressure Drop ◽

Phase Change ◽

Constant Heat Flux ◽

Working Fluid ◽

Microchannel Flow ◽

Carrier Fluid ◽

Volume Fractions ◽

Energy Equations

In the present study, a numerical model was developed for laminar flow in a microchannel with a suspension of microsized phase change material (PCM) particles. In the model, the carrier fluid and the particles are simultaneously present, and the mass, momentum, and energy equations are solved for both the fluid and particles. The particles are injected into the fluid at the inlet at a temperature equal to the temperature of the carrier fluid. A constant heat flux is applied at the bottom wall. The temperature distribution and pressure drop in the microchannel flow were predicted for lauric acid microparticles in water with volume fractions ranging from 0 to 8%. The particles show heat transfer enhancements by decreasing the temperature distribution in the working fluid by 39% in a 1 mm long channel. Meanwhile, particle blockage in the flow passage was found to have a negligible effect on pressure drop in the range of volume fractions studied. This work is a first step towards providing insight into increasing heat transfer rates with phase change-based microparticles for applications in microchannel cooling and solar thermal systems.

Download Full-text

Combination Effect of Baffle Arrangement and Hybrid Nanofluid on Thermal Performance of a Shell and Tube Heat Exchanger Using 3-D Homogeneous Mixture Model

Mathematics ◽

10.3390/math9080881 ◽

2021 ◽

Vol 9 (8) ◽

pp. 881

Author(s):

Mashhour A. Alazwari ◽

Mohammad Reza Safaei

Keyword(s):

Heat Exchanger ◽

Pressure Drop ◽

Thermal Performance ◽

Heat Removal ◽

Hybrid Nanofluid ◽

Distilled Water ◽

Reference Case ◽

Maximum Heat ◽

Tube Heat Exchanger ◽

Shell And Tube

In this study, thermal performance and flow characteristics of a shell and tube heat exchanger equipped with various baffle angles were studied. The heat exchanger was operated with distilled water, and a hybrid nanofluid at three concentrations of 0.04% and 0.10% of GNP-Ag/water within Reynolds numbers ranged between 10,000 and 20,000. The thermophysical properties of nanofluid varied with temperature and nanoparticles’ concentration. The baffle angles were set at 45°, 90°, 135°, and 180°. Results showed that the calculated Nusselt number (Nu) could be improved by adding nanoparticles to the distilled water or increasing the fluid’s Reynolds number. At a low Re number, the Nu corresponding to baffle angle of 135° was very close to that recorded for the angle of 180°. At Re = 20,000, the Nu number was the highest (by 35% compared to the reference case), belonging to a baffle angle of 135°. Additionally, results related to friction factor and pressure drop showed that more locations with fluid blocking were observed by increasing the baffle angle, resulting in increased pressure drop value and friction. Finally, the temperature streamlines counter showed that the best baffle angle could be 135° in which maximum heat removal and the best thermal performance can be observed.

Download Full-text

Design and Analysis of double- stacked Heat Exchanger for Brewery Application

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.a1673.059120 ◽

2020 ◽

Vol 9 (1) ◽

pp. 1793-1798

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Pressure Drop ◽

Heat Transfer Rate ◽

Flow Rate ◽

Transfer Rate ◽

Working Fluid ◽

Support Weight ◽

Tube Heat Exchanger ◽

Shell And Tube

A heat exchanger is a device intensively used for enhancing the transfer of heat energy between two or more working fluids at different temperature, which are in thermal contact. The optimal design and efficient operation of heat exchanger and heat transfer network are of a great significance in any of the process industry. The heat transfer efficiency depends on both design of heat exchanger and property of working fluid. From various types of heat exchanger, the double stacked shell and tube heat exchanger with straight tube and single pass is to be under study. Here the redesign of heat exchanger takes place with the key objectives of optimizing the pressure drop, optimizing the heat transfer rate and reducing the saddle support weight used for cooling purpose in brewery application. The design calculations are carried out using the Kerns and Bell Delwar method and other important parameters dealing with material selection and geometries are also taken into consideration. FEA analysis for optimizing the saddle support weight is carried out using Dassault systeme’s Solidworks while the CFD analysis for optimizing pressure drop and heat transfer rate is carried out using Dassault systeme’s Solidworks analysis software and the design and working of Shell and tube heat exchanger is determined in terms of variables such as pressure ,temperature ,mass flow rate ,flow rate ,energy input output that are of particular interest in Shell and tube heat exchanger analysis.

Download Full-text