Heat transfer enhancement of microchannel heat sink using transcritical carbon dioxide as the coolant

Leng, Chuan; Wang, Xiaodong; Yan, Wei‐Mon; Wang, Tianhu

doi:10.1016/j.enconman.2015.12.006

Cited by 39 publications

(10 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Consequently, the sinusoidal flow channel has been reported to significantly enhance heat/mass transfer, especially in compact exchange devices [4,5]. Also, some authors have reported the idea of using this wavy configuration as a substitute to the conventional rectangular microchannel and as a means of enhancing heat transfer performance [2,6]. Despite the significantly improved heat transfer performance peculiar to these configurations, the pressure drop increase is one of the inherent penalties [1].…”

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of Liquid Water Transport Dynamics in Novel Hybrid Sinusoidal Flow Channel Designs for PEMFC

et al. 2019

View full text Add to dashboard Cite

This study numerically investigates liquid water dynamics in a novel hybrid sinusoidal flow channel of a proton exchange membrane fuel cell (PEMFC). The two-phase flow is examined using a three-dimensional, transient computational fluid dynamics (CFD) simulation employing the coupled level set and volume of fluid (VOF) method. Simulations for hybrid and non-hybrid sinusoidal flow channels, including a straight flow channel, are compared based on their water exhaust capacities and pressure drops. Additionally, the effects of inlet gas velocity, wall wettability, and droplet interaction in the flow channel on the dynamic behaviour of liquid water are investigated. Results reveal that the novel hybrid sinusoidal channel designs are consistent in terms of quicker water removal under varying hydrophilic wall conditions. Also, it is found that the liquid surface coverage, detachment, and removal rate depends on droplet proximity to the walls, inlet gas velocity, and wall contact angle. Also, the time a droplet makes contact with the side walls affect the discharge time. Additionally, there is an improvement in the gas velocity magnitude and vertical component velocity across the hybrid sinusoidal channel designs. Therefore, the unique geometric configuration of the proposed hybrid Design makes it a viable substitute for water management in PEMFC applications.

show abstract

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of Liquid Water Transport Dynamics in Novel Hybrid Sinusoidal Flow Channel Designs for PEMFC

et al. 2019

View full text Add to dashboard Cite

show abstract

“…This gives a preliminary insight as to which coolants are better for use in the AWG system's heat sink. The papers which used the Al2O3/H2O Nanofluid, Transcritical CO2, Supercritical CO2 coolants for their experiments, did not provide such data for analysis [26][27][28][29][30].…”

Section: Coolantmentioning

confidence: 99%

“…The TiO2/H2O nanofluid's dynamic viscosity was not provided and thus, it cannot be concluded from this data whether it is a more suitable coolant than the Galinstan. [26,30] (c) The required pumping power of supercritical CO2 is plotted against the thermal resistance [30].…”

Section: Coolant Type Densitymentioning

confidence: 99%

Increasing the efficiency of a Peltier device by assessing the thermal performance of liquid-cooled microchannel heat sinks

Sharpe

Burhanuddin

Majcan

et al. 2020

PAMR

View full text Add to dashboard Cite

Water is, arguably, Earth's most valuable and vital resource. Devices that extract water from the atmosphere have been intensely researched as a means of harvesting potable water in environments where it is otherwise scarce. One such device is a Thermoelectric Cooler (TEC); a device that utilises the Peltier effect to cool a system. TECs are a promising solution for atmospheric water generation (AWG) over their competitors due to their simplicity and refrigeration capabilities. Despite these advantages, TECs are still considered mostly inefficient as they demand relatively high costs and energy consumption. This meta-analysis focuses on optimising the efficiency of small-scale Peltier devices. It explores the means of optimising the liquid cooled heat sink by using a specific flow field microchannel configuration such that less pumping power is required to push the coolant and more energy can be saved. A combination of optimal operating current of the Peltier device and of a novel flow liquid-cooled microchannel heatsink configuration with bifurcated fins using Galinstan as a coolant promises a significant increase in water production per unit of energy consumption for the AWG system.

show abstract

“…Natural working fluids such as ammonia (NH3), hydrocarbons and carbon dioxide (CO2) are attractive options for next generation refrigerants since they have zero ozone depletion potentials (ODP) and low global warming potentials (GWP). Among the natural working fluids, CO2 is a promising refrigerant due to its favourable characteristics (non-toxic, non-flammable, high volumetric cooling capacity) and eco-friendly properties (ODP=0, GWP=1) so CO2 has been used in heat pumps (Byrne et al, 2009), air conditioners and other industrial processes (Kouta et al, 2016;Milani et al, 2017;Hou et al, 2017;Leng et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

Modeling of the Heat Transfer in a Supercritical Co2/Dme Mixture Flowing in Cooled Helically Coiled Tubes

Ba¹,

Chen²,

Li³

2021

Frontiers in Heat and Mass Transfer

View full text Add to dashboard Cite

The heat transfer of supercritical CO2/DME mixtures was modeled in this study for a mass ratio of 95/5 for cooling in horizontal helically coiled tubes. The CO2/DME heat transfer coefficient was higher in the high-temperature zone than with pure CO2. The heat transfer of CO2/DME (95/5) was predicted for various mass fluxes, heat fluxes and pressures. The CO2/DME heat transfer coefficient increased with the mass flux due to the increased turbulent diffusion, and first increased but then decreased with the heat flux. The peak heat transfer coefficient of CO2/DME shifted toward the high-temperature region as the operating pressure increased. The effects of buoyancy and the centrifugal force were also analyzed to better understand the heat transfer mechanisms in helically coiled tubes. The gravitational buoyancy effect on the heat transfer decreased with mass flux while increased with heat flux. Higher heat fluxes strengthened the centrifugal buoyancy effect on the heat transfer at the beginning of the cooling process but weakened the centrifugal buoyancy effect later in the cooling process. The present study gives insight into the flow and heat transfer processes in helically coiled tubes which is useful for heat exchanger designs and refrigerant selection.

show abstract

Heat transfer enhancement of microchannel heat sink using transcritical carbon dioxide as the coolant

Cited by 39 publications

References 34 publications

Numerical Investigation of Liquid Water Transport Dynamics in Novel Hybrid Sinusoidal Flow Channel Designs for PEMFC

Numerical Investigation of Liquid Water Transport Dynamics in Novel Hybrid Sinusoidal Flow Channel Designs for PEMFC

Increasing the efficiency of a Peltier device by assessing the thermal performance of liquid-cooled microchannel heat sinks

Modeling of the Heat Transfer in a Supercritical Co2/Dme Mixture Flowing in Cooled Helically Coiled Tubes

Contact Info

Product

Resources

About