The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform

Ben Richard Hughes - One of the best experts on this subject based on the ideXlab platform.

  • a novel design of a desiccant rotary wheel for passive ventilation applications
    Applied Energy, 2016
    Co-Authors: Dominic Oconnor, John Kaiser Calautit, Ben Richard Hughes
    Abstract:

    Rotary desiccant wheels are used to regulate the relative humidity of airstreams. These are commonly integrated into Heating, Ventilation and Air-Conditioning units to reduce the relative humidity of incoming ventilation air. To maximise the surface area, desiccant materials are arranged in a honeycomb matrix structure which results in a high Pressure Drop across the device requiring fans and blowers to provide adequate ventilation. This restricts the use of rotary desiccant wheels to mechanical ventilation systems. Passive ventilation systems are able to deliver adequate ventilation air but cannot control the humidity of the incoming air. To overcome this, the traditional honeycomb matrix structure of rotary desiccant wheels was redesigned to maintain a Pressure Drop Value below 2 Pa, which is required for passive ventilation purposes. In addition to this, the temperature of the regeneration air for desorption was lowered. Radial blades extending out from the centre of a wheel to the circumference were coated in silica gel particles to form a rotary desiccant wheel. Computational Fluid Dynamics (CFD) modelling of the design was validated using experimental data. Reduction in relative humidity up to 55% was seen from the system whilst maintaining a low Pressure Drop across the new design. As an outcome of the work presented in this paper, a UK patent GB1506768.9 has been accepted.

Mohammad Mohsen Sarafraz - One of the best experts on this subject based on the ideXlab platform.

  • Assessment of Iron Oxide (III)–Therminol 66 Nanofluid as a Novel Working Fluid in a Convective Radiator Heating System for Buildings
    Energies, 2019
    Co-Authors: Mohammad Mohsen Sarafraz, Mohammad Reza Safaei, Marjan Goodarzi, Reza Ghomashchi, Alireza Dareh Baghi, Arturo S. Leon, Cheng-xian Lin
    Abstract:

    This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a convective heating system with potential heating applications in the buildings sector. In an experimental study, characteristics of nanofluids were measured, including heat capacity, thermal conductivity, and density. The influences of mass flow rate and concentration of nanofluid on various parameters were quantified, such as Pressure loss, friction coefficient, and heat transfer rate. For a concentration of 0.3 wt.%, the heat transfer increased by 46.3% and the Pressure Drop increased by 37.5%. The latter is due to the higher friction and viscosity of the bulk of the nanofluid. Although the Pressure Drop is higher, the thermo-hydraulic efficiency still increased by 19%. As a result, iron oxide (III)–therminol 66 presented reasonable thermal performance, higher heat transfer coefficient, and a lower Pressure Drop Value (19% better performance in comparison with water) for the air–liquid convective system. Results also showed that for nanosuspensions at 0.3 wt.%, the friction factor of the system increased by 10% in comparison with the performance of the system with water.

  • heat transfer analysis of ga in sn in a compact heat exchanger equipped with straight micro passages
    International Journal of Heat and Mass Transfer, 2019
    Co-Authors: Mohammad Mohsen Sarafraz, Mohammad Reza Safaei, Marjan Goodarzi, B Yang, Maziar Arjomandi
    Abstract:

    Abstract In the present work, an experimental study was conducted to quantify the heat transfer coefficient of a liquid metal mixture including gallium, indium and tin (Ga-In-Sn) under various heat fluxes inside a compact heat exchanger equipped with rectangular micro-passages. The microchannel was fabricated from Cu/Zn alloy using computer numerical control machining (CNC) to provide a plausible heat transfer. The experiments were conducted at 200–350 °C and for peristaltic mass flow rate of 0.1–1.5 gr/s. Pressure Drop and also temperature profile along with the length of the microchannel were constantly measured and it was identified that Ga-In-Sn eutectic had a plausible thermal response at temperatures >200 °C. Also, the Pressure Drop Value decreased with an increase in the temperature of the system. Also, an increase in the temperature of the system improved the heat transfer coefficient, while friction factor slightly changed with the temperature of the system. For all the experiments, the thermo-hydraulic evaluation parameter was >1 reaching to 1.3 at the highest temperature (T = 300 °C) and for the largest peristaltic flow rate (G = 1.5 gr/s). Also, a rough comparison between the correlations developed for the liquid metals and the experimental data showed that the results were in a good agreement with the equation developed by Seban-Shimazaki.

  • Thermal analysis and thermo-hydraulic characteristics of zirconia–water nanofluid under a convective boiling regime
    Journal of Thermal Analysis and Calorimetry, 2019
    Co-Authors: Mohammad Mohsen Sarafraz, Ahmad Raza Khan, Zhe Tian, Iskander Tlili, Mohammad Reza Safaei
    Abstract:

    In this research, flow boiling heat transfer of zirconia–water nanofluid inside a heat exchanger was experimentally investigated. The system was assessed for heat fluxes ranging from 10 to 150 kW m^−2, inlet temperatures of 323 K to 353 K, mass flow rates of 1–10 kg s^−1 and mass concentrations of mass% = 0.1 to 0.3%. Results showed that the boiling thermal performance and heat transfer coefficient of zirconia nanofluid are plausible and this nanofluid can be utilized as a coolant inside the two-phase heat exchanging systems. However, the Pressure Drop associated with the use of zirconia nanoparticles suppressed the thermal efficiency of the system. Likewise, particulate fouling was not observed during the experiments and bubble formation was not affected by the deposition of nanoparticles on the boiling surface. At mass% = 0.3, the boiling heat transfer coefficient was improved by 35.8%; however, Pressure Drop Value was also augmented. Likewise, temperature increased the heat transfer coefficient slightly which was attributed to the improvement in the thermo-physical properties of nanofluid such as thermal conductivity.

  • Fluid and heat transfer characteristics of aqueous graphene nanoplatelet (GNP) nanofluid in a microchannel
    International Communications in Heat and Mass Transfer, 2019
    Co-Authors: Mohammad Mohsen Sarafraz, B Yang, Maziar Arjomandi, O. Pourmehran, Reza Ghomashchi
    Abstract:

    Abstract In the present work, thermo-physical properties of aqueous Graphene Nanoplatelet (GNP) at various mass concentrations of GNPs was experimentally measured. An experimental investigation was conducted to quantify the heat transfer coefficient, friction factor, Pressure Drop Value, pumping power and thermo-hydraulic performance index of the nanofluid within a microchannel at various heat flux and Reynolds number. Results showed that GNP/water nanofluid can plausibly enhance the heat transfer coefficient and the Nusselt number by ~80%. In addition, a small increase in the friction factor and the Pressure Drop Value was seen, which was attributed to the augmentation in the friction forces. The maximum increase in the Pressure Drop was 18.3% recorded at the highest Reynolds number and the highest mass concentration of the nanofluid. Also, despite the augmentation in the Pressure Drop Value, the thermal performance of the system increased by 76% showing the great potential of the GNP/water nanofluid cooling and/or heating applications despite ~20% augmentation in the pumping power at Reynolds number > 1376. The enhancement in the thermal performance of the system was attributed to the thermophoresis effect, Brownian motion and the enhancement in the thermal conductivity of the nanofluid due to the presence of the GNP nanoplatelets.

Dominic Oconnor - One of the best experts on this subject based on the ideXlab platform.

  • a novel design of a desiccant rotary wheel for passive ventilation applications
    Applied Energy, 2016
    Co-Authors: Dominic Oconnor, John Kaiser Calautit, Ben Richard Hughes
    Abstract:

    Rotary desiccant wheels are used to regulate the relative humidity of airstreams. These are commonly integrated into Heating, Ventilation and Air-Conditioning units to reduce the relative humidity of incoming ventilation air. To maximise the surface area, desiccant materials are arranged in a honeycomb matrix structure which results in a high Pressure Drop across the device requiring fans and blowers to provide adequate ventilation. This restricts the use of rotary desiccant wheels to mechanical ventilation systems. Passive ventilation systems are able to deliver adequate ventilation air but cannot control the humidity of the incoming air. To overcome this, the traditional honeycomb matrix structure of rotary desiccant wheels was redesigned to maintain a Pressure Drop Value below 2 Pa, which is required for passive ventilation purposes. In addition to this, the temperature of the regeneration air for desorption was lowered. Radial blades extending out from the centre of a wheel to the circumference were coated in silica gel particles to form a rotary desiccant wheel. Computational Fluid Dynamics (CFD) modelling of the design was validated using experimental data. Reduction in relative humidity up to 55% was seen from the system whilst maintaining a low Pressure Drop across the new design. As an outcome of the work presented in this paper, a UK patent GB1506768.9 has been accepted.

Mohammad Reza Safaei - One of the best experts on this subject based on the ideXlab platform.

  • Assessment of Iron Oxide (III)–Therminol 66 Nanofluid as a Novel Working Fluid in a Convective Radiator Heating System for Buildings
    Energies, 2019
    Co-Authors: Mohammad Mohsen Sarafraz, Mohammad Reza Safaei, Marjan Goodarzi, Reza Ghomashchi, Alireza Dareh Baghi, Arturo S. Leon, Cheng-xian Lin
    Abstract:

    This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a convective heating system with potential heating applications in the buildings sector. In an experimental study, characteristics of nanofluids were measured, including heat capacity, thermal conductivity, and density. The influences of mass flow rate and concentration of nanofluid on various parameters were quantified, such as Pressure loss, friction coefficient, and heat transfer rate. For a concentration of 0.3 wt.%, the heat transfer increased by 46.3% and the Pressure Drop increased by 37.5%. The latter is due to the higher friction and viscosity of the bulk of the nanofluid. Although the Pressure Drop is higher, the thermo-hydraulic efficiency still increased by 19%. As a result, iron oxide (III)–therminol 66 presented reasonable thermal performance, higher heat transfer coefficient, and a lower Pressure Drop Value (19% better performance in comparison with water) for the air–liquid convective system. Results also showed that for nanosuspensions at 0.3 wt.%, the friction factor of the system increased by 10% in comparison with the performance of the system with water.

  • heat transfer analysis of ga in sn in a compact heat exchanger equipped with straight micro passages
    International Journal of Heat and Mass Transfer, 2019
    Co-Authors: Mohammad Mohsen Sarafraz, Mohammad Reza Safaei, Marjan Goodarzi, B Yang, Maziar Arjomandi
    Abstract:

    Abstract In the present work, an experimental study was conducted to quantify the heat transfer coefficient of a liquid metal mixture including gallium, indium and tin (Ga-In-Sn) under various heat fluxes inside a compact heat exchanger equipped with rectangular micro-passages. The microchannel was fabricated from Cu/Zn alloy using computer numerical control machining (CNC) to provide a plausible heat transfer. The experiments were conducted at 200–350 °C and for peristaltic mass flow rate of 0.1–1.5 gr/s. Pressure Drop and also temperature profile along with the length of the microchannel were constantly measured and it was identified that Ga-In-Sn eutectic had a plausible thermal response at temperatures >200 °C. Also, the Pressure Drop Value decreased with an increase in the temperature of the system. Also, an increase in the temperature of the system improved the heat transfer coefficient, while friction factor slightly changed with the temperature of the system. For all the experiments, the thermo-hydraulic evaluation parameter was >1 reaching to 1.3 at the highest temperature (T = 300 °C) and for the largest peristaltic flow rate (G = 1.5 gr/s). Also, a rough comparison between the correlations developed for the liquid metals and the experimental data showed that the results were in a good agreement with the equation developed by Seban-Shimazaki.

  • Thermal analysis and thermo-hydraulic characteristics of zirconia–water nanofluid under a convective boiling regime
    Journal of Thermal Analysis and Calorimetry, 2019
    Co-Authors: Mohammad Mohsen Sarafraz, Ahmad Raza Khan, Zhe Tian, Iskander Tlili, Mohammad Reza Safaei
    Abstract:

    In this research, flow boiling heat transfer of zirconia–water nanofluid inside a heat exchanger was experimentally investigated. The system was assessed for heat fluxes ranging from 10 to 150 kW m^−2, inlet temperatures of 323 K to 353 K, mass flow rates of 1–10 kg s^−1 and mass concentrations of mass% = 0.1 to 0.3%. Results showed that the boiling thermal performance and heat transfer coefficient of zirconia nanofluid are plausible and this nanofluid can be utilized as a coolant inside the two-phase heat exchanging systems. However, the Pressure Drop associated with the use of zirconia nanoparticles suppressed the thermal efficiency of the system. Likewise, particulate fouling was not observed during the experiments and bubble formation was not affected by the deposition of nanoparticles on the boiling surface. At mass% = 0.3, the boiling heat transfer coefficient was improved by 35.8%; however, Pressure Drop Value was also augmented. Likewise, temperature increased the heat transfer coefficient slightly which was attributed to the improvement in the thermo-physical properties of nanofluid such as thermal conductivity.

John Kaiser Calautit - One of the best experts on this subject based on the ideXlab platform.

  • a novel design of a desiccant rotary wheel for passive ventilation applications
    Applied Energy, 2016
    Co-Authors: Dominic Oconnor, John Kaiser Calautit, Ben Richard Hughes
    Abstract:

    Rotary desiccant wheels are used to regulate the relative humidity of airstreams. These are commonly integrated into Heating, Ventilation and Air-Conditioning units to reduce the relative humidity of incoming ventilation air. To maximise the surface area, desiccant materials are arranged in a honeycomb matrix structure which results in a high Pressure Drop across the device requiring fans and blowers to provide adequate ventilation. This restricts the use of rotary desiccant wheels to mechanical ventilation systems. Passive ventilation systems are able to deliver adequate ventilation air but cannot control the humidity of the incoming air. To overcome this, the traditional honeycomb matrix structure of rotary desiccant wheels was redesigned to maintain a Pressure Drop Value below 2 Pa, which is required for passive ventilation purposes. In addition to this, the temperature of the regeneration air for desorption was lowered. Radial blades extending out from the centre of a wheel to the circumference were coated in silica gel particles to form a rotary desiccant wheel. Computational Fluid Dynamics (CFD) modelling of the design was validated using experimental data. Reduction in relative humidity up to 55% was seen from the system whilst maintaining a low Pressure Drop across the new design. As an outcome of the work presented in this paper, a UK patent GB1506768.9 has been accepted.