scholarly journals Flow Field Effect on the Performance of Direct Formic Acid Membraneless Fuel Cells: A Numerical Study

Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 746
Author(s):  
Jin-Cherng Shyu ◽  
Sheng-Huei Hung
Keyword(s):  
Fuel Cells ◽  
Flow Field ◽  
Formic Acid ◽  
Power Density ◽  
Liquid Flow ◽  
Numerical Study ◽  
Air Flow ◽  
Airflow Rate ◽  
Air Breathing ◽  
Membraneless Fuel Cells

The performance of both air-breathing and air-feeding direct formic acid membraneless fuel cells (DFAMFCs) possessing different flow fields were numerically investigated in this study at given concentration and flow rate for both fuel and electrolyte. Single serpentine, stepwise broadening serpentine, multi-serpentine and parallel channel were tested as liquid flow field, while single serpentine, stepwise broadening serpentine, multi-serpentine and pin channel were tested as air flow field. The channel width was either 0.8 mm or 1.3 mm. The simulation results showed that the air-breathing DFAMFC having identical flow field for both fuel and electrolyte yielded highest cell output. The air-breathing DFAMFC having SBS liquid flow field yielded a maximum power density of 10.5 mW/cm2, while the air-breathing DFAMFC having S(1.3) liquid flow field produced an open circuit voltage of 1.0 V owing to few formic acid penetration into the cathode. Concerning the air-feeding DFAMFCs, the DFAMFC having SBS liquid flow field and MS(0.8) air flow field yielded highest peak power density, 12 mW/cm2, at an airflow rate of 500 sccm. Considering the power generated by the DFAMFCs together with the power consumed by the air pump, DFAMFC having SBS liquid flow field and Pin(0.8) air flow field could be the preferred design.

scholarly journals Experimental and Numerical Study of Proton Exchange Membrane Fuel Cells with a Novel Compound Flow Field

ACS Omega ◽  
2021 ◽  
Vol 6 (34) ◽  
pp. 21892-21899
Author(s):  
Yixiang Wang ◽  
Lei Wang ◽  
Xianhang Ji ◽  
Yulu Zhou ◽  
Mingge Wu
Keyword(s):  
Fuel Cells ◽  
Flow Field ◽  
Proton Exchange Membrane ◽  
Numerical Study ◽  
Proton Exchange ◽  
Exchange Membrane

scholarly journals A twin-fluid injector for FCC feed injection

2019 ◽  
Vol 4 (3) ◽  
pp. 109-115
Author(s):  
Deepak Kumar ◽  
Tushar Sikroria ◽  
Kushari A ◽  
Pramod Kumar ◽  
Sriganesh G
Keyword(s):  
Droplet Size ◽  
Flow Rate ◽  
Liquid Flow ◽  
Liquid Flow Rate ◽  
Air Flow ◽  
Product Yield ◽  
Droplet Velocity ◽  
Injection System ◽  
Airflow Rate ◽  
Air Flow Rate

In Fluidized Bed Catalytic Cracking (FCC) process, hydrocarbon feed undergoes vapour phase cracking in presence of hot regenerated catalyst to produce valuable products like LPG, Gasoline and Diesel. FCC feed injection system is most critical hardware component of FCC unit in order to get desired product yield by minimizing the undesirable dry gas and coke yield. Typically, twin-fluid nozzles (hydrocarbon and stream) are used to atomize the feed. In the present study, a twin-fluid injector, with an internal impactor to minimize the droplet size and velocity, is designed, developed and characterized. The performance of the feeding injector was evaluated using water and air as operating fluids and the droplet size and velocity were measured 150 mm downstream of the injector tip using a PDPA system for different water and air flow rates. The average droplet size (D32) showed an increase while the droplet velocity remained almost constant with the increase in the liquid flow rate for a given flow rate of air, consistent with the increase in droplet size with decreasing air-liquid ratio for twin–fluid atomizers. But, for a given liquid flow rate, the droplet SMD decreased and the droplet velocity increased with increasing airflow rate, which can be attributed to the increase in overall kinetic energy due to the increase in air flow rate. The flow rate of liquid was seen to be independent of air flow rate unlike conventional twin-fluid atomizers. The droplet size was found to be a function of ALR and the local volume flux of the droplets was found to be a function of the liquid flow rate.

scholarly journals Numerical study on the polymer drawing of the spunbonding process

2015 ◽  
Vol 19 (4) ◽  
pp. 1473-1474
Author(s):  
Li-Li Wu ◽  
Kang Yang ◽  
Ting Chen
Keyword(s):  
Flow Field ◽  
Numerical Computation ◽  
Numerical Study ◽  
Air Flow ◽  
Filament Diameter

A polymer drawing model is established for the spunbonding process through numerical computation of the air flow field. The results show that the model predicts the filament diameter effectively. The paper contributes to in-depth understanding of the spunbonding technology.

Forced Flow Heat and Mass Transfer to a Cylinder Surrounded by a Porous Material With Applications to NBC Protective Clothing

2002 ◽  
Author(s):  
Michael P. Sobera ◽  
Chris R. Kleijn ◽  
Paul Brasser ◽  
Harry E. A. Van den Akker
Keyword(s):  
Mass Transfer ◽  
Flow Field ◽  
Heat And Mass Transfer ◽  
Protective Clothing ◽  
Numerical Study ◽  
Air Flow ◽  
Forced Flow ◽  
Dimensionless Numbers ◽  
Flow Heat ◽  
Human Limb

Increased permeability of clothing material can reduce the heat load caused by Nuclear-Biological-Chemical (NBC) protective clothing, but implies reduced protection. The goal of the present work is to study the influence of the air permeability on human comfort and safety. A numerical study is presented of the air flow with heat and mass transfer around a cylinder, mimicking a human limb, placed in a turbulent external air flow and surrounded by protective clothing. The problem is described in terms of the relevant dimensionless numbers. The dependence of the flow field underneath the clothing and the heat and mass transfer to the limb are studied as a function of the Reynolds, Darcy and Damko¨hler numbers, which are a measure for the wind speed, clothing permeability and adsorptivity of the poisonous gas, respectively. The air flow simulations are validated with experiments, in which the flow field around a bare cylinder and in the space between a cylinder and its porous cover, is measured with LDA. Scaling rules for heat and mass transfer are presented.

Toward geometrical design improvement of membraneless fuel cells: Numerical study

2013 ◽  
Vol 38 (34) ◽  
pp. 14791-14800 ◽  
Author(s):  
Rafael Abraham García-Cuevas ◽  
Ilse Cervantes ◽  
Luis Gerardo Arriaga ◽  
Irwin Allen Diaz-Diaz
Keyword(s):  
Fuel Cells ◽  
Numerical Study ◽  
Geometrical Design ◽  
Design Improvement ◽  
Membraneless Fuel Cells

Improved Thermal Uniformity by Introducing Tree-Like Flowing Channels in a PEMFC Flow-Field Plate

2017 ◽  
Author(s):  
Yuxin Jia ◽  
Rui Zhu ◽  
Bengt Sunden ◽  
Gongnan Xie
Keyword(s):  
Fuel Cells ◽  
Flow Field ◽  
Proton Exchange Membrane ◽  
Numerical Study ◽  
Flow Characteristics ◽  
Flow Channel ◽  
Proton Exchange ◽  
Field Plate ◽  
Flow Channels ◽  
Exchange Membrane

Thermal uniformity in the flow field plate of proton exchange membrane fuel cells (PEMFCs) is crucial for their power generating efficiency and reliability and therefore, has attracted much attention. The present numerical study is an attempt to optimize the flow channels via replacement of convectional zigzag continuous channels by tree-like bifurcated channels radially outwards. The numerical model is validated by experimental data available in the open literature. The effects of included angles and length ratios among the channels on thermal uniformity are analyzed based on detailed fluid flow characteristics. Results show that tree-like channels outperform conventional ones. It is found that tree-like flow channels can improve thermal uniformity of proton exchange membrane fuel cells. Within limits, with smaller angle between bifurcated flow channels and length ratio 2−1/3 between higher flow channel and lower flow channel, PEMFC can obtain the most uniform temperature distribution in Y shape tree-liked flow field.

Numerical study of two-phase flow patterns in the gas channel of PEM fuel cells with tapered flow field design

2014 ◽  
Vol 39 (5) ◽  
pp. 2261-2273 ◽  
Author(s):  
Erasmo Mancusi ◽  
Éliton Fontana ◽  
Antônio Augusto Ulson de Souza ◽  
Selene M.A. Guelli Ulson de Souza
Keyword(s):  
Fuel Cells ◽  
Flow Field ◽  
Two Phase Flow ◽  
Numerical Study ◽  
Pem Fuel Cells ◽  
Flow Patterns ◽  
Phase Flow ◽  
Two Phase ◽  
Gas Channel ◽  
Flow Field Design
Sign in / Sign up

Export Citation Format

Share Document