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  • 1. Ahangar Zonouzi, S.
    et al.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Safarzadeh, H.
    Aminfar, H.
    Trushkina, Y.
    Mohammadpourfard, M.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Salazar Alvarez, G.
    Experimental investigation of the flow and heat transfer of magnetic nanofluid in a vertical tube in the presence of magnetic quadrupole field2018In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 91, p. 155-165Article in journal (Refereed)
    Abstract [en]

    In this paper, the effects of applying magnetic field on hydrodynamics and heat transfer of Fe3O4/water magnetic nanofluid flowing inside a vertical tube have been studied experimentally. The applied magnetic field was resulted from quadrupole magnets located at different axial positions along the tube length. The variations of the local heat transfer coefficient and also the pressure drop of the ferrofluid flow along the length of the tube by applying the magnetic quadrupole field have been investigated for different Reynolds numbers. The obtained experimental results show maximum enhancements of 23.4%, 37.9% and 48.9% in the local heat transfer coefficient for the magnetic nanofluid with 2 vol% Fe3O4 in the presence of the quadrupole magnets located at three different axial installation positions for the Reynolds number of 580 and the relative increase in total pressure drop by applying the magnetic field is about 1% for Re = 580. The increase of the heat transfer coefficient is due to the radial magnetic force toward the heated wall generated by magnetic quadrupole field acting over the ferrofluid flowing inside the tube so that the velocity of the ferrofluid in the vicinity of the heated wall is increased. It is also observed that the enhancement of heat transfer coefficient by applying magnetic quadrupole is decreased with increasing the Reynolds number.

  • 2.
    Behi, Hamidreza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Behi, Mohammadreza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Investigation of PCM-assisted heat pipe for electronic cooling2017In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 127, p. 1132-1142Article in journal (Refereed)
    Abstract [en]

    Today, higher-power computer chips are available, but they generate too much heat that irreparably damages inside components. In this paper, a horizontal phase change material (PCM)-assisted heat pipe system for electronic cooling was introduced as a potential solution to this problem. A computational fluid dynamic model was developed and validated to assist the investigation. A surface temperature profile along the heat pipe was used to validate the CFD model. The liquid fraction and temperature distribution of PCM were reported during the charging process at different input powers. It was found that the PCM-assisted heat pipe provided up to 86.7% of the required cooling load in the working power range of 50-80 W. Contribution of PCM was calculated to be 11.7% of the provided cooling load and preventing heat dissipation.

  • 3.
    Behi, Mohammadreza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Univ Sydney, Sch Chem & Biomol Engn, Sydney, NSW 2006, Australia..
    Mirmohammadi, Seyed Aliakbar
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Univ Sydney, Sch Civil Engn, Sydney, NSW 2006, Australia..
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Behi, Hamidreza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Evaluation of a novel solar driven sorption cooling/heating system integrated with PCM storage compartment2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 164, p. 449-464Article in journal (Refereed)
    Abstract [en]

    Recently the interest in solar thermal cooling has been growing for Air Conditioning (AC) applications. This paper presents an applied experimental and numerical evaluation of a novel triple-state sorption solar cooling module. The performance of a LiCl-H2O based sorption module (SM) for cooling/heating system with integration of an external energy storage has been evaluated. The dynamic behavior of the SM, which can be driven by solar energy, is presented. Two PCM assisted configurations of the SM have been studied herein; (i) PCM assisted sorption module for cooling applications (ii) PCM assisted sorption module for heating applications. Initially, an experimental investigation was carried out to evaluate the charging/discharging process of the SM without external energy storage. Secondly, the initial experimental configuration was modeled with a PCM integrated storage compartment. The PCM storage compartment was connected to the Condenser/Evaporator (C/E) of the SM. The temporal history of the sorption module's C/E and PCM storage, the cyclic and average performance in terms of cooling/heating capacity, cooling/heating COP, and the total efficiency were experimentally and numerically investigated. Furthermore, PCM charging/discharging power rate and solidification/melting process of the PCM in the integrated storage compartment to the SM were predicted by the model.

  • 4.
    Bitaraf Haghighi, Ehsan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Utomo, Adi T.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Zavareh, Ashkan I. T.
    Nowak, Emilia
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Pacek, Andrzej
    Palm, Björn E.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Combined effect of physical properties and convective heat transfer coefficient of nanofluids on their cooling efficiency2015In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 68, p. 32-42Article in journal (Refereed)
    Abstract [en]

    The advantages of using Al2O3, TiO2, SiO2 and CeO2 nanofluids as coolants have been investigated by analysing the combined effect of nanoparticles on thermophysical properties and heat transfer coefficient. The thermal conductivity and viscosity of these nanofluids were measured at two leading European universities to ensure the accuracy of the results. The thermal conductivity of nanofluids agreed with the prediction of the Maxwell model within +/- 10% even at elevated temperature of 50 oC indicating that the Brownian motion of nanoparticles does not affect thermal conductivity of nanofluids. The viscosity of nanofluids is well correlated by modified Krieger-Dougherty model providing that the effect of nanoparticles aggregation is taken into account. It was found that at the same Reynolds number the advantage of using a nanofluid increases with increasing nanofluid viscosity which is counterintuitive. At the same pumping power nanofluids do not offer any advantage in terms of cooling efficiency over base fluids since the increase in viscosity outweighs the enhancement of thermal conductivity.

  • 5.
    Bitaraf Haghighi, Ehsan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Utomo, Adi T.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Zavareh, Ashkan I. T.
    Poth, Heiko
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Pacek, Andrzej
    Palm, Bjoern E.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Experimental study on convective heat transfer of nanofluids in turbulent flow: Methods of comparison of their performance2014In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 57, p. 378-387Article in journal (Refereed)
    Abstract [en]

    Turbulent convective heat transfer coefficients of 9 wt% Al2O3/water and TiO2/water nanofluids inside a circular tube were investigated independently at the Royal Institute of Technology, KTH (Sweden) and at University of Birmingham (UK). The experimental data from both laboratories agreed very well and clearly show that Nusselt numbers are well correlated by the equations developed for single phase fluids with the thermophysical properties of nanofluid. The heat transfer coefficients of nanofluids can be compared with those of the base fluids at the same Reynolds number or at the same pumping power. As the same Reynolds number requires higher flow rate of nanofluids therefore such comparison shows up to 15% increase in heat transfer coefficient. However, at equal pumping power, the heat transfer coefficient of Al2O3 nanofluid was practically the same as that of water while that of TiO2 was about 10% lower. Comparing performance at equal Reynolds number is clearly misleading since the heat transfer coefficient can always be increased by increased pumping power, accordingly, the comparison between the fluids should be done at equal pumping power.

  • 6.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Bitaraf Haghigi, Ehsan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Thermal properties and rheological behavior of water based Al2O3 nanofluid as a heat transfer fluid2014In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 53, p. 227-235Article in journal (Refereed)
    Abstract [en]

    An experimental investigation and theoretical study of thermal conductivity and viscosity of Al2O3/water nanofluids are presented in this article. Various suspensions containing Al2O3 nanoparticles were tested in concentration ranging from 3% to 50% in mass and temperature ranging from 293K to 323K. The results reveal that both the thermal conductivity and viscosity of nanofluids increase with temperature and particle concentration accordingly while the increase in viscosity is much higher than the increase in thermal conductivity. The thermal conductivity and viscosity enhancement are in the range of 1.1-87% and 18.1-300%, respectively. Moreover, the results indicate that the thermal conductivity increases nonlinearly with concentration, but, linearly with the increase in temperature. In addition, the experimental results are compared with some existing correlations from literature and some modifications are suggested. Finally, the average heat transfer coefficient at different basis of comparisons including equal Reynolds number, fluid velocity and pumping power is studied based on the experimental thermal conductivity and viscosity in fully developed laminar and turbulent flow regimes. It is found that equal Reynolds number as a basis of comparison is highly misleading and equal pumping power can be used to study the advantage of using nanofluid instead of the base fluid.

  • 7.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Entropy generation analysis of cylindrical heat pipe using nanofluid2015In: Thermochimica Acta, ISSN 0040-6031, E-ISSN 1872-762X, Vol. 610, p. 37-46Article in journal (Refereed)
    Abstract [en]

    Thermal performance of cylindrical heat pipe with nanofluid is studied based on the laws of thermodynamics. The objective of the present work is to investigate nanofluids effect on different sources of entropy generation in heat pipe caused by heat transfer between hot and cold reservoirs and also frictional losses and pressure drop in the liquid and vapor flow along heat pipe. An analytical study was performed to formulate all sources of entropy generation and the predicted results are compared with experimental ones. Cylindrical miniature grooved heat pipes of 250 mm length and 6.35 mm outer diameter were fabricated and tested with distilled water and water based TiO2 and Al2O3 nanofluids at different concentrations as working fluids. Analytical and experimental results revealed that the entropy generation in heat pipes decreases when nanofluids are used as working fluids instead of basefluid which results in improved thermal performance of the heat pipes with nanofluids.

  • 8.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Vafai, K.
    An investigation of thermal performance improvement of a cylindrical heat pipe using Al2O3 nanofluid2016In: Heat and Mass Transfer, ISSN 0947-7411, E-ISSN 1432-1181, p. 1-11Article in journal (Refereed)
    Abstract [en]

    In this study, effect of Al2O3 nanofluid on thermal performance of cylindrical heat pipe is investigated. An analytical model is employed to study the thermal performance of the heat pipe utilizing nanofluid and the predicted results are compared with the experimental results. A substantial change in the heat pipe thermal resistance, effective thermal conductivity and entropy generation of the heat pipe is observed when using Al2O3 nanofluid as a working fluid. It is found that entropy generation in the heat pipe system decreases when using a nanofluid due to the lower thermal resistance of the heat pipe which results in an improved thermal performance. It is shown that the proposed model is in reasonably good agreement with the experimental results and can be used as a fast technique to explore various features of thermal characteristics of the nanofluid based heat pipe.

  • 9.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nikkam, N.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Improvement of heat transfer characteristics of cylindrical heat pipe by using SiC nanofluids2015In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 90, p. 127-135Article in journal (Refereed)
    Abstract [en]

    An experimental study was performed to investigate the thermal performance of heat pipes using SiC/water nanofluid as the working fluid. Four cylindrical copper heat pipes containing two layers of screen mesh were fabricated and tested with water and water based SiC nanofluids with nanoparticle mass concentrations of 0.35%, 0.7% and 1.0% as working fluids. SiC nanofluids properties and characteristics are evaluated and its effects on thermal performance improvement of screen mesh heat pipes at different concentrations and inclination angles are investigated. Experimental results show that nanofluid improves the performance of the heat pipes and the thermal resistance of the heat pipe with SiC nanofluid decreases with increasing nanoparticle concentration. Thermal resistance reduction of heat pipes by 11%, 21% and 30% was observed with SiC nanofluids containing 0.35 wt.%, 0.7 wt.% and 1.0 wt.% SiC nanoparticles as compared with water. In addition, it is revealed that the inclination angle has remarkable influence on the thermal performance of the heat pipes and the lowest thermal resistance belongs to the inclination angle of 60 in all concentrations. The present investigation indicates that the maximum heat removal capacity of the heat pipe increases by 29% with SiC nanofluids at nanoparticle mass concentration of 1.0 wt.%.

  • 10.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental study of nanofluid effect on thermal performance of screen mesh heat pipe2013Conference paper (Refereed)
  • 11.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Thermal performance of inclined screen mesh heat pipes using silver nanofluids2015In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 67, p. 14-20Article in journal (Refereed)
  • 12.
    Ghanbarpourgeravi, Morteza
    KTH, School of Industrial Engineering and Management (ITM).
    Investigation of Thermal Performance of Cylindrical Heatpipes Operated with Nanofluids2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Nanofluids as an innovative class of heat transfer fluids created by dispersing nanometre-sizedmetallic or non-metallic particles in conventional heat transfer fluids displayed the potential toimprove the thermophysical properties of the heat transfer fluids. The main purpose of this study is toinvestigate the influence of the use of nanofluids on two-phase heat transfer, particularly on thethermal performance of the heat pipes. In the first stage, the properties of the nanofluids were studied,then, these nanofluids were used as the working fluids of the heat pipes. The thermal performance ofthe heat pipes when using different nanofluids was investigated under different operating conditionsexperimentally and analytically. The influences of the concentration of the nanofluids, inclinationangles and heat loads on the thermal performance and maximum heat flux of the heat pipes wereinvestigated.This study shows that the thermal performance of the heat pipes depends not only on thermophysicalproperties of the nanofluids but also on the characteristics of the wick structure through forming aporous coated layer on the heated surface. Forming the porous layer on the surface of the wick at theevaporator section increases the wettability and capillarity and also the heat transfer area at theevaporator of the heat pipes.The thermal performance of the heat pipes increases with increasing particle concentration in all cases,except for the heat pipe using 10 wt.% water/Al2O3 nanofluid. For the inclined heat pipe, irrespectiveof the type of the fluid used as the working fluid, the thermal resistance of the inclined heat pipes waslower than that of the heat pipes in a horizontal state, and the best performance was observed at theinclination angle of 60o, which is in agreement with the results reported in the literature. Otheradvantages of the use of nanofluids as the working fluids of the heat pipes which were investigated inthis study were the increase of the maximum heat flux and also the reduction of the entropy generationof the heat pipes when using a nanofluid.These findings revealed the potential for nanofluids to be used instead of conventional fluids as theworking fluid of the heat pipes, but the commercialization of the heat pipes using nanofluids for largescale industrial applications is still a challenging question, as there are many parameters related to thenanofluids which are not well understood.

  • 13. Haghighi, Ehsan Bitaraf
    et al.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    A Hybrid Cooling System for Telecommunicatioin Base Stations2016In: 2016 IEEE International Telecommunications Energy Conference (INTELEC), Institute of Electrical and Electronics Engineers (IEEE), 2016, article id 7749149Conference paper (Refereed)
    Abstract [en]

    Huge amount of energy is consumed by a typical telecommunication base station in order to keep the indoor climate temperature low enough to avoid any damage to IT/electronic equipment. By increasing the number telecommunication base stations applying more energy efficient cooling strategies are urgently needed. Free cooling either in direct approach (e.g. extracting fresh air), or indirect approach (e.g. thermosiphon or air to air heat exchanger) is a well-proven strategy to reduce the total power consumption for cooling telecommunication base stations. This article proposes a hybrid cooling system, which is an integrated vapour compression unit with a thermosiphon unit in a single frame. In such a hybrid system the indoor air circulates through a closed loop with minimal interaction with the outdoor air. This article suggests a model to control and estimate the potential of energy savings by a hybrid cooling system. Based on the results for an indoor temperature set point of 25 degrees C the cooling load provides by the hybrid system can be divided among three different operating modes: 0-59% ( thermosiphon), 12-41% (dual mode), and 12-88% (air conditioning) depending on the location of the base stations.

  • 14.
    Mirmohammadi, Seyed Aliakbar
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Behi, Mohammadreza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Cooling performance study of a novel heat exchanger in an absorption system2019In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 180, p. 1001-1012Article in journal (Refereed)
    Abstract [en]

    The paper is focusing on a shell and plate heat exchanger of a novel absorption refrigeration system. The system is composed of two vacuum vessels connected together with a steam channel and one heat exchanger is located in each vessel. The first heat exchanger is called reactor where working fluid and salt exist and the second heat exchanger or evaporator/condenser (C/E) is where only water exists. The propylene glycol-based (PG) heat transfer fluid is used on the shell side of both heat exchangers as the media to exchange the heat between boilers and reactor in one vessel and between cold environment and condenser/evaporator in another vessel. An experimental test rig was built to investigate the performance of the evaporator/condenser heat exchanger. Then, a three-dimensional (3D) Computational Fluid Dynamics (CFD) model was developed. The experimental result was then used to validate the numerical model developed by using Ansys/Fluent software. A parametric study has been intended to find a more appropriate design for the heat exchanger in order to increase heat transfer performance. Results of the parametric study demonstrated that the cooling performance is doubled by increasing the diameter of the plate from 0.14 m to 0.2 m. In addition, to obtain the maximum heat transfer performance, Reynolds number and distance between plates should be 9 and 0.5 m, respectively. Two correlations have been developed for the outlet temperature and cooling power of the heat exchanger which are functions of heat transfer coefficient. The results of this study can be of vital importance for improving the cooling power of the system, remarkably.

  • 15.
    Morteza, Ghanbarpourgeravi
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Nader, Nikkam
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Mohammet S
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Muhammed, Mamoun Ali
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Thermal performance of screen mesh heat pipe with Al2O3 nanofluid2015In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 66, p. 213-220Article in journal (Refereed)
    Abstract [en]

    This study presents the effect of Al2O3 nanofluid (NF) on thermal performance of screen mesh heat pipe in cooling applications. Three cylindrical copper heat pipes of 200 mm length and 6.35 mm outer diameter containing two layers of screen mesh were fabricated and tested with distilled water and water based Al2O3 NF with mass concentrations of 5% and 10% as working fluids. To study the effect of NF on the heat pipes thermal performance, the heat input is increased and then decreased consecutively and the heat pipes surface temperatures are measured at steady state conditions. Results show that using 5 wt.% of Al2O3 NF improves the thermal performance of the heat pipe for increasing and decreasing heat fluxes compared with distilled water, while utilizing 10 wt.% of Al2O3 NF deteriorates the heat pipe thermal performance. For heat pipe with 5 wt.% Al2O3 NF the reduction in thermal resistance of the heat pipe is found to be between 6% and 24% for increasing and between 20% and 55% for decreasing heat fluxes, while the thermal resistance increased between 187% and 206% for increasing and between 155% and 175% for decreasing steps in heat pipe with 10 wt.% of Al2O3 NF.

  • 16. Nikkam, N.
    et al.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    The effect of particle size and base liquid on thermo-physical properties of ethylene and diethylene glycol based copper micro- and nanofluids2017In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 86, p. 143-149Article in journal (Refereed)
    Abstract [en]

    Nanofluid (NF) is a fluid containing nanometer-sized particles. The present work investigates, experimentally and theoretically, on fabrication and thermo-physical properties evaluation of ethylene glycol and diethylene glycol (EG/DEG) based nanofluids/microfluids (NFs/MFs) containing copper nanoparticles/microparticles (NPs/MPs) with focus on the effect of the particle size and the base liquid. A series of stable Cu NFs and MFs with various NP/MP concentration (1, 2 and 3 wt%) were fabricated by dispersing Cu NPs and Cu MPs in EG and DEG as the base liquids. The physicochemical properties of Cu NFs and MFs were analyzed by various techniques including X-Ray diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS). The thermo-physical properties including thermal conductivity (TC) and viscosity of EG/DEG based Cu NFs/MFs were measured at 20 to 40 °C. The results for TC and viscosity of EG based Cu NF/MFs were compared to the same NFs/MFs with DEG base liquid with focus on the impact of the particle size as well as the base liquid. The experiments showed that EG based NFs/MFs exhibit more favorable characteristics than that of DEG based ones. Moreover, NFs with Cu NPs revealed higher TC than those MFs containing Cu MPs at the same particle concentration and temperature (effect of NP size). As the best result, a TC enhancement of ~ 4.7% was achieved for EG based NF with 3 wt% Cu NP while maximum increase in viscosity of ~ 1.8% was observed for the same NF at 20 °C. To compare the experimental results with the estimated values, Maxwell predictive correlation and Corcione model were employed while Einstein equations as well as Kriger-Dougherty correlation were applied for TC and viscosity of NFs/MFs, respectively.

  • 17.
    Nikkam, Nader
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, Rahmaatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental investigation on thermophysical properties of ethylene glycol based copper micro- and nanofluids for heat transfer applications2015In: Materials Research Society Symposium Proceedings, Cambridge University Press, 2015, p. 69-74Conference paper (Refereed)
    Abstract [en]

    The present work reports on the fabrication, experimental and theoretical investigatbn of thermal conductivity (TC) and viscosity of ethylene glycol (EG) based nanofluids/microfluids (NFs/MFs) containing copper nanoparticles (Cu NPs) and copper microparticles (Cu MPs). Cu NPs (20-40 nm) and Cu MPs (0.5-1.5 μm) were dispersed in EG with particle concentration from 1 wt% to 3 wt% using powerful ultrasonic agitation, and to study the real impact of dispersed particles the use of surface modifier was avoided. The objectives were to study the effect of concentration and impact of size of Cu particles on thermo-physical properties, including thermal TC and viscosity, of EG based Cu NFs/MFs. The physicochemical properties of NPs/MPs and NFs/MFs were characterized by using various techniques. The experimental results exhibited higher TC of NFs and MFs than the EG base liquid. Moreover, Cu NFs displayed higher TC than MFs showing their potential for use in some heat transfer applications. Maxwell effective medium theory as well as Einstein law of viscosity was used to compare the experimental data with the predicted values for estimating the TC and viscosity of Cu NFs/MFs, respectively.

  • 18.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Haghighi, Ehsan Bitaraf
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental investigation on thermo-physical properties of copper/diethylene glycol nanofluids fabricated via microwave-assisted route2014In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 65, no 1-2, p. 158-165Article in journal (Refereed)
    Abstract [en]

    This study investigates the fabrication, thermal conductivity and rheological characteristics evaluation of nanofluids consisting of copper nanoparticles in diethylene glycol base liquid. The fabricated Cu nanofluids displayed enhanced thermal conductivity over the base liquid. Copper nanoparticles were directly formed in diethylene glycol using microwave-assisted heating, which provides uniform heating of reagents and solvent, accelerating the nucleation of metal clusters, resulting in monodispersed nanostructures. Copper nanoparticles displayed an average primary particle size of 75 ± 25 nm from SEM micrographs, yet aggregated to form large spherical particles of about 300 nm. The physicochemical properties including thermal conductivity and viscosity of nanofluids were measured for the nanofluids with nanoparticle concentration between 0.4 wt% and 1.6 in the temperature range of 20-50 C. Proper theoretical correlations/models were applied to compare the experimental results with the estimated values for thermal conductivity and viscosity of nanofluids. For all cases, thermal conductivity enhancement was higher than the increase in viscosity showing the potential of nanofluids to be utilized as coolant in heat transfer applications. A thermal conductivity enhancement of ∼7.2% was obtained for nanofluids with 1.6 wt% nanoparticles while maximum increase in viscosity of ∼5.2% was observed for the same nanofluid.

  • 19.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Thermal and rheological properties of micro- and nanofluids of copper in diethylene glycol: as heat exchange liquid2013In: Nanoscale Thermoelectric Materials: Thermal and Electrical Transport, and Applications to Solid-state Cooling and Power Generation, Cambridge: Cambridge Scholars Publishing, 2013, , p. 6p. 165-170Conference paper (Refereed)
    Abstract [en]

    This study reports on the fabrication of nanofluids/microfluids (NFs/MFs) with experimental and theoretical investigation of thermal conductivity (TC) and viscosity of diethylene glycol (DEO) base NFs/MFs containing copper nanoparticles (Cu NPs) and copper microparticles (Cu MPs). For this purpose, Cu NPs (20-40 nm) and Cu MPs (0.5-1.5 urn) were dispersed in DEG with particle loading between 1 wt% and 3 wt%. Ultrasonic agitation was used for dispersion and preparation of stable NFs/MFs, and thus the use of surfactants was avoided. The objectives were investigation of impact of size of Cu particle and concentration on TC and viscosity of NFs/MFs on DEG as the model base liquid. The physicochemical properties of all particles and fluids were characterized by using various techniques including Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS) techniques. Fourier Transform Infrared Spectroscopy (FTIR) analysis was performed to study particles' surfaces. NFs and MFs exhibited a higher TC than the base liquid, while NFs outperformed MFs showing a potential for their use in heat exchange applications. The TC and viscosity of NFs and MFs were presented, along with a comparison with values from predictive models. While Maxwell model was good at predicting the TC of MFs, it underestimated the TC of NFs, revealing that the model is not directly applicable to the NF systems.

  • 20.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Bitaraf Haghighi, Ehsan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Design and Fabrication of Efficient Nanofluids Based on SiC Nanoparticles for Heat Exchange Applications2013Conference paper (Other academic)
  • 21.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Haghighi, Ehsan Bitaraf
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Fabrication, Characterization and Thermo-physical Property Evaluation of SiCNanofluids for Heat Transfer Applications2014In: Nano-Micro Letters, ISSN 2150-5551, Vol. 6, no 2, p. 178-189Article in journal (Refereed)
    Abstract [en]

    Nanofluids (NFs) are nanotechnology-based colloidal suspensions fabricated by suspending nanoparticles (NPs) in a base liquid. These fluids have shown potential to improve the heat transfer properties of conventional heat transfer fluids. In this study we report in detail on the fabrication, characterization and thermo-physical property evaluation of SiC NFs, prepared using SiC NPs with different crystal structure, for heat transfer applications.  For this purpose, a series of SiC NFs containing SiC NPs with different crystal structure (α-SiC and β-SiC) were fabricated in a water (W)/ethylene glycol (EG) mixture (50/50 wt % ratio). Physicochemical properties of NPs/NFs were characterized by using various techniques such as powder X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) and Zeta Potential Analysis were performed. Thermo-physical properties including thermal conductivity (TC) and viscosity for NFs containing SiC particles (α- and β- phase) were measured. The results showed among all suspensions, NF fabricated with α-SiC particles have more favorable thermo-physical properties compared to the NFs fabricated with β-SiC; the observed difference was attributed to combination of several factors, including crystal structure (β- vs. α-), sample purity, and residual chemicals exhibited on SiC nanoparticles. A TC enhancement of ~20% while 14% increased viscosity were obtained for a NF containing 9wt% of particular type of α-SiC NPs indicating promising capability of these kind of NFs for further heat transfer characteristics investigations. 

  • 22.
    Singh, Sathya P.
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Design and Evaluation of Carbon Nanotube Based Nanofluids for Heat Transfer Applications2013In: MRS Spring 2013 Proceedings: Symposium on Nanoscale Heat Transport—From Fundamentals to Devices, Materials Research Society, 2013Conference paper (Refereed)
    Abstract [en]

    The present work investigates the fabrication, thermal conductivity (TC) and rheological properties of water based carbon nanotubes (CNTs) nanofluids (NFs) prepared using a two-step method. As-received (AR) CNTs heated and the effect of heat treatment was studied using X-ray diffraction and thermogravimetric analysis. The AR-CNTs and heat-treated CNTs (HT-CNTs) were dispersed with varying concentration of surface modifiers Gum Arabic (GA) and TritonX-100 (TX) respectively. It was found that heat treatment of CNTs effectively improved the TC and influenced rheological properties of NFs. Scanning electron microscopy analysis revealed TX modified NFs showed better dispersion ability compared to GA. Surface modification of the CNTs was confirmed by Fourier Transformation Infrared (FTIR) analysis. Zeta potential measurement showed the stability region for GA modified NFs in the pH range of 5-11, whereas pH was between 9.5-10 for TX NFs. The concentration of surface modifier plays an extensive role on both TC and rheological behavior of NFs. A maximum TC enhancement of 10% with increases in viscosity around 2% for TX based HT-CNTs NFs was measured. Finally comparison of experimental TC results with the predicted values obtained from a model demonstrated inadequacy of the predictive model for CNT NFs system.

  • 23. Utomo, Adi T.
    et al.
    Haghighi, Ehsan B.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Zavareh, Ashkan I. T.
    Ghanbarpourgeravi, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Poth, Heiko
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Pacek, Andrzej W.
    The effect of nanoparticles on laminar heat transfer in a horizontal tube2014In: International Journal of Heat and Mass Transfer, ISSN 0017-9310, E-ISSN 1879-2189, Vol. 69, p. 77-91Article in journal (Refereed)
    Abstract [en]

    Heat transfer coefficient in laminar flow of water-based alumina, titania and carbon nanotube nanofluids in a straight pipe with constant heat flux at the wall have been investigated independently by two universities. The nanoparticles affect the thermo-physical properties of the suspensions, however, nanopartides presence and movement due to Brownian diffusion and thermophoresis seemed to have insignificant effect on heat transfer coefficient. The Nusselt number of all investigated nanofluids followed standard heat transfer correlations developed for liquids within +/- 10% suggesting that all investigated nanofluids can be treated as homogenous fluids. Different methods of comparison between heat transfer coefficient in nanofluids and base fluid are also critically discussed.

1 - 23 of 23
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