scholarly journals Comparative analysis between methane and hydrogen regarding ignition and combustion in diffusive mode

2021 ◽  
Vol 327 ◽  
pp. 01001
Author(s):  
Lucian Mihăescu ◽  
Dorin Stanciu ◽  
Gheorghe Lăzăroiu ◽  
Ionel Pîșă ◽  
Gabriel Negreanu

The hydrogen is expected to become the energy vector of the future. If for environmental protection this concept it is obvious, the data for the design of hydrogen combustion facilities are still insufficient. This paper discusses the fundamental actions related to the design of a hydrogen burner. Numerical modelling researches using the Ansys-Fluent software has shown the link between the flow velocity in combustible gas jets together with the required air and the combustion rates. Combustion models (both analytical and numerical) allowed finding the optimal ratios between the two specified velocities (combustion and flow) compared to those for methane combustion, correlated also with the classical directions and recommendations for the burner design.

Author(s):  
Mahbub Ahmed ◽  
Cheng Zhang ◽  
Scott McKay ◽  
Vivek Shirsat ◽  
Jobaidur Khan

Hydrocarbon-based miniature power generators are promising any many application since hydrocarbon based fuels have higher power densities compared to conventional lithium batteries. A 40mm long meso-combustor of two different configurations, two-inlet and three-inlet, were used to investigate the combustion of methane in the meso-chamber. A non-premixed combustion of methane and oxygen was simulated numerically using a steady laminar flamelet model. The mesh generation and the CFD simulation were performed using ANSYS FLUENT software. A a finite volume approach was used for the simulation. The fuel-oxidizer mixing, thermal behavior and fuel burning efficiency were studied. An adequate mixing that supports the combustion was observed in certain locations. The exhaust gas was analyzed experimentally. The temperature distributions were also observed to predict the flame locations. According to the numerical analysis it was apparent that the flame would be anchored in the well mixed regions of the chamber the flames were found to be attached in two distinct locations. One in the upstream zone and the other one in the downstream zone. Another important finding was that the fuel lean condition produced higher efficiency than the fuel rich condition.


2011 ◽  
Vol 308-310 ◽  
pp. 136-141
Author(s):  
Yan Chao Qiao ◽  
Zi Qi Guo ◽  
Bao Gang Zhang ◽  
Yao Lin Shi

in order to optimize the air-pod shape, this paper details work conducted using the commercial CFD software package ANSYS: Fluent to simulate the aerodynamic of air-pod. In our research, the results as followed: 1) In the benchmark, our comparative analysis of the flow over the NASA 0012 airfoil from the Experimental Data Base for Computer Program Assessment (AGARD-AR-138, 1979) implies that the ANSYS: Fluent software package numerical method simulates the airfoil viscous flow with the same accuracy as the wind-tunnel experiment. We can use it to finish our research. 2) We build the 3-D model to compute the aerodynamic of the air-pod. We choose the cylinder at first step. From the results we can see the pressure and wall shear concentrate at the side face of the cylinder. The pressure at the side faces is about twice than the direct side. Next step we will compute different models, such as spherical and drop-shaped, et al. then we can compare the pressure and wall shear field value for different models at different conditions. This work gives us best way to optimize the aerodynamic shape of air-pod.


Author(s):  
Vladimíra Michalcová ◽  
Sergej Kuznětsov ◽  
Stanislav Pospíšil

Abstract The article describes air flow turbulent attributes in the enclosed chamber of a rectangular cross-section contraction for the purpose of confirming its optimal shape. The task is solved numerically using Ansys Fluent software. Right models were selected based on the evaluated results at a contraction's outlet which were compared to the physics experiment


2019 ◽  
Vol 85 ◽  
pp. 04003
Author(s):  
Nelu-Cristian Cherecheş ◽  
Cătălin George Popovici ◽  
Vasile Valerică Cîrlan ◽  
Sebastian Valeriu Hudişteanu

The objective of the study was to perform a numerical analysis in order to determine the best position for placing sunscreen inside the channel of a double skin façade insulation relative to dynamic insulation efficiency, using ANSYS-Fluent software. The analysis was performed for summer conditions in forced convection for two airspeed regimes inside the channel: 0.2m/s and respectively 0.5m/s. Regime is considered permanent and the only parameter changed is the position of the blinds in the channel. Results are shown by spectra and profiles of temperature and velocity in order to analyse thermodynamic behaviour of a double skin façade. The numerical results emphasize that effectiveness of sunscreen such as blinds, is proportional to the flow velocity inside the channel and inversely proportional to the distance from the outer glazing. Ranked as the most effective sun protection is when it is located at the outer glazing and air velocity at the entrance is 0.5m/s.


2019 ◽  
Vol 7 (1) ◽  
pp. 43-53
Author(s):  
Abbas Jassem Jubear ◽  
Ali Hameed Abd

The heat sink with vertically rectangular interrupted fins was investigated numerically in a natural convection field, with steady-state heat transfer. A numerical study has been conducted using ANSYS Fluent software (R16.1) in order to develop a 3-D numerical model.  The dimensions of the fins are (305 mm length, 100 mm width, 17 mm height, and 9.5 mm space between fins. The number of fins used on the surface is eight. In this study, the heat input was used as follows: 20, 40, 60, 80, 100, and 120 watts. This study focused on interrupted rectangular fins with a different arrangement and angle of the fins. Results show that the addition of interruption in fins in various arrangements will improve the thermal performance of the heat sink, and through the results, a better interruption rate as an equation can be obtained.


2014 ◽  
Vol 703 ◽  
pp. 425-429
Author(s):  
Jun Fei Wu ◽  
Zhi Li ◽  
Fan Guo Meng ◽  
Ben Liang Yu

Compared with traditional screw pump,all-metal screw pump have more advantages in the oil extraction. In this paper, all-metal single screw pump's geometric model was made by PROE software; then the dynamic mesh technique was applied to mesh the model and constraint condition was applied in the ANSYS-FLUENT software. 3D flow field was numerical analyzed In that software, the impacts of screw speed on volume flow and volumetric efficiency were concluded, the conclusion can offer some valuable guidances to the all-metal single screw pump's design.


2015 ◽  
Vol 9 (3) ◽  
pp. 161-166
Author(s):  
Aneta Bohojło-Wiśniewska

Summary This paper presents an example of humid air flow around a single head of Chinese cabbage under conditions of complex heat transfer. This kind of numerical simulation allows us to create a heat and humidity transfer model between the Chinese cabbage and the flowing humid air. The calculations utilize the heat transfer model in porous medium, which includes the temperature difference between the solid (vegetable tissue) and fluid (air) phases of the porous medium. Modelling and calculations were performed in ANSYS Fluent 14.5 software.


Author(s):  
Александр Анатольевич Дектерев ◽  
Артем Александрович Дектерев ◽  
Юрий Николаевич Горюнов

Исследование направлено на разработку и апробацию методики численного моделирования аэродинамических и энергетических характеристик циклоидального ротора. За основу взята конфигурация ротора IAT21 L3. Для нее с использованием CFD-пакета ANSYS Fluent построена математическая модель и выполнен расчет. Проанализировано влияние скорости набегающего потока воздуха на движущийся ротор. Математическая модель и полученные результаты исследования могут быть использованы при создании летательных аппаратов с движителями роторного типа. This article addresses the study of the aerodynamic and energy characteristics of a cycloidal rotor subject to the influence of the incoming flow. Cycloidal rotor is one of the perspective devices that provide movement of aircrafts. Despite the fact that the concept of a cycloidal rotor arose in the early twentieth century, the model of a full-scale aircraft has not been yet realized. Foreign scientists have developed models of aircraft ranging in weight from 0.06 to 100 kg. The method of numerical calculation of the cycloidal rotor from the article [1] is considered and realized in this study. The purpose of study was the development and testing of a numerical simulation method for the cycloidal rotor and study aerodynamic and energy characteristics of the rotor in the hovering mode and under the influence of the oncoming flow. The aerodynamic and energy characteristics of the cycloidal rotor, rotating at a speed of 1000 rpm with incoming flow on it with velocities of 20-80 km/h, were calculated. The calculation results showed a directly proportional increase of thrust with an increase of the incoming on the rotor flow velocity, but the power consumed by the rotor was also increased. Increase of the incoming flow velocity leads to the proportional increasing of the lift coefficient and the coefficient of drag. Up to a speed of 80 km/h, an increase in thrust and power is observed; at higher speeds, there is a predominance of nonstationary effects and difficulties in estimating the aerodynamic characteristics of the rotor. In the future, it is planned to consider the 3D formulation of the problem combined with possibility of the flow coming from other sides.


2015 ◽  
Author(s):  
Nilima C. Joshi ◽  
Ayaz J. Khan

ost of the flow phenomena important to modern technology involve turbulence. Propellers generally operate in the very complex flow field that may be highly turbulent and spatially non-uniform. Propeller skew is the single most effective design parameter which has significant influence on reducing propeller induced vibration. Up to date applications of propeller skew does not has a specified criteria for any turbulent model. This paper deals with the model which explains the effect of propeller skewness on hydrodynamic performance related to study of turbulent model via mathematical and numerical modeling. The simulation work is carried out using ANSYS-FLUENT software.


Sign in / Sign up

Export Citation Format

Share Document