scholarly journals Numerical Investigation of a Wood-Chip Downdraft Gasifier

2019 ◽  
Vol 113 ◽  
pp. 01002
Author(s):  
Alessandro Vulpio ◽  
Nicola Casari ◽  
Mirko Morini ◽  
Michele Pinelli ◽  
Alessio Suman
Keyword(s):  
Numerical Model ◽  
Test Bench ◽  
Wood Chip ◽  
Biomass Gasification ◽  
Careful Analysis ◽  
Good Match ◽  
Energy Field ◽  
Downdraft Gasifier ◽  
Virtual Test ◽  
Working Parameters

Biomass gasification is regarded as one of the most promising technology in the renewable energy field. The outcome of such operation, i.e. the synfuel, can be exploited in several ways, for example powering engines and turbines, and is considered more flexible than the biomass itself. For this reason, a careful analysis of the gasification performance is of paramount importance for the optimization of the process. One of the techniques that can be used for such a purpose, is the numerical analysis. CFD is indeed a tool that can be of great help in the design and study of the operation of the gasifier, allowing for an accurate prediction of the operating parameters. In this work, a downdraft gasifier is considered, and the biomass is made of wood chip. The present analysis is devoted to build the numerical model and simulate all the reactions that happen inside an actual gasifier, considering the drying of the wood chip, heating, pyrolysis, and combustion. Good match with experimental results is found, making the numerical model here presented a reliable virtual test bench where investigating the effects of variation in the working parameters.

Downdraft gasifier design calculation for biomass gasification using exhaust gas as a gasification agent

2021 ◽  
Author(s):  
Sherif Elshokary ◽  
Sherif Farag ◽  
OSayed Sayed Mohamed Abu-Elyazeed ◽  
Bitu Hurisso ◽  
Mostafa Ismai
Keyword(s):  
Biomass Gasification ◽  
Design Calculation ◽  
Exhaust Gas ◽  
Downdraft Gasifier

scholarly journals A virtual test bench for determining the loads in the air suspension of the rear trolley of a truck at the early stages of design

2021 ◽  
Vol 1 (3) ◽  
pp. 76-86
Author(s):  
R.O. Maksimov ◽  
◽  
I.V. Chichekin ◽  
Keyword(s):  
Mathematical Model ◽  
Test Bench ◽  
Software Tools ◽  
Rigid Bodies ◽  
Virtual Test ◽  
Early Stages ◽  
Air Suspension ◽  
Solid Suspension ◽  
Suspension Model ◽  
Standard Software

To determine the maximum loads acting in the rear air suspension of a truck at the early stages of design there was used computer modeling based on solving equations of dynamics of solids and implemented in the Recurdyn software. The components of the developed virtual test bench, includ-ing hinges, power connections, drive axles, a wheel-hub assembly with a wheel and a support plat-form, are considered in detail. The test bench is controlled using a mathematical model created in the environment for calculating the dynamics of rigid bodies and associated with a solid suspension model by standard software tools of the application. The test bench is controlled using a mathemati-cal model created in the environment for calculating the dynamics of rigid bodies and associated with a solid suspension model by standard software tools of the application. The use of such a test bench makes it possible to determine the loads in the hinges and power connections of the suspen-sion, to determine the mutual positions of the links for each load mode, to increase the accuracy of the calculation of loads in comparison with the flat kinematic and force calculation. The mathemati-cal model of the virtual test bench allows to carry out numerous parametric studies of the suspension without the involvement of expensive full-scale prototypes. This makes it possible at the early stages of design to determine all hazardous modes, select rational parameters of the elements, and reduce design costs. The paper shows the results of modeling the operation of a virtual test bench with an air suspen-sion in the most typical loading modes, identifying the most dangerous modes. The efficiency and adequacy of the mathematical model of the suspension was proved. Examples of determining the force in all the joints of the structure, the choice of maximum loads for design calculations when designing the air suspension of vehicle were shown.

scholarly journals On-Line Open-Phase Fault Detection Method for Switched Reluctance Motors with Bus Current Measurement

Actuators ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 117
Author(s):  
Alejandra de la Guerra ◽  
Victor M. Jimenez-Mondragon ◽  
Lizeth Torres ◽  
Rafael Escarela-Perez ◽  
Juan C. Olivares-Galvan
Keyword(s):  
Test Bench ◽  
Angular Position ◽  
Current Measurement ◽  
Switched Reluctance Motors ◽  
Switched Reluctance ◽  
Virtual Test ◽  
Open Phase ◽  
On Line ◽  
Different Sources ◽  
A Current

This article introduces an on-line fault diagnosis (FD) system to detect and recognize open-phase faults in switched reluctance motors (SRMs). Both tasks, detection and recognition, are based on functions built with the same information but from different sources. Specifically, these functions are constructed from bus current measurement provided by a sensor and from the estimate of such a current provided by an extended Kalman filter (EKF) that performs the estimation from only rotor angular position measurements. In short, the FD system only requires two measurements for employment: bus current and angular position. In order to show its efficacy, results from numerical simulations (performed in a virtual test bench) are presented. Specifically, these simulations involve the dynamics of the SRM, including the magnetic phenomena caused by the analyzed faults. The motor dynamics were obtained with finite element simulations, which guarantee results close to the actual ones.

Wood Chip Gasification in a Commercial Downdraft Gasifier

1985 ◽  
pp. 911-921 ◽  
Author(s):  
Walter P. Walawender ◽  
S. M. Chern ◽  
L. T. Fan
Keyword(s):  
Wood Chip ◽  
Downdraft Gasifier

scholarly journals Study on Evolutionary Characteristics of Toppling Deformation of Anti-Dip Bank Slope Based on Energy Field

2020 ◽  
Vol 12 (18) ◽  
pp. 7544
Author(s):  
Liangfu Xie ◽  
Qingyang Zhu ◽  
Yongjun Qin ◽  
Jianhu Wang ◽  
Jiangu Qian
Keyword(s):  
Numerical Model ◽  
Kinetic Energy ◽  
Fracture Surface ◽  
Shear Deformation ◽  
Strain Energy ◽  
Energy Field ◽  
Bank Slope ◽  
Shallow Layer ◽  
Friction Energy ◽  
Toppling Deformation

The evolution of toppling deformation of anti-dip slope is essentially a process of energy dissipation and transformation. Aiming to study the characteristics of energy evolution in different stages, the DEM (discrete element method) software PFC (Particle Flow Code) was utilized to establish a two-dimensional numerical model for a bank slope in Chongqing based on geological background data and field investigation. The DEM model was proven to be reliable not only because the deformation discrepancy between the numerical model and actual bank slope was not large but also because some obvious fractures in the actual bank slope can readily be found in the numerical model as well. In this article, content about displacement in the shallow layer was analyzed briefly. Special effort was made to analyze the energy field and divide the toppling deformation process into three stages. (1) Shear deformation stage: this is an energy accumulating stage in which the strain energy, friction energy, and kinetic energy are all small and the deformation is mainly shear deformation in the slope toe. (2) Stage of main toppling fracture surface hole-through: all three kinds of energy present the increasing trend. The shear deformation in the slope toe expands further, and the toppling deformation also appears in the middle and rear parts of the bank slope. (3) Stage of secondary toppling and fracture surface development: strain energy and friction energy increase steadily but kinetic energy remains constant. Deformation consists mainly of secondary shearing and a fracture surface in the shallow layer. Secondary toppling and fracture surface develop densely.

Simulation of High Temperature Air – Steam Biomass Gasification in a Downdraft Gasifier Using ASPEN PLUS

2012 ◽  
Vol 267 ◽  
pp. 57-63
Author(s):  
Worapot Ngamchompoo ◽  
Kittichai Triratanasirichai
Keyword(s):  
High Temperature ◽  
Process Model ◽  
Waste Heat ◽  
Aspen Plus ◽  
Biomass Gasification ◽  
Pilot Scale ◽  
Producer Gas ◽  
Downdraft Gasifier ◽  
High Heating Value ◽  
Cold Gas Efficiency

A comprehensive process model is developed for high temperature air – steam biomass gasification in a downdraft gasifier using the ASPEN PLUS simulator. The simulation results are compared with the experimental data obtained through pilot scale downdraft gasifier. In this study, the model is used to investigate the effects of gasifying agent preheating, equivalence ratio (ER), and steam/biomass (S/B) on producer gas composition, high heating value (HHV), and cold gas efficiency (CGE). Results indicate that H2 and CO contents have increased when gasifying agent preheating is used, while gasifying agent preheating has no effect with H2 and CO at high ER. At high level of S/B, the concentrations of H2 and CO are related with water-gas shift reaction in significant. HHV and CGE depend on the concentrations of H2 and CO in producer gas, which can increase by preheated gasifying agent. However, gasifying agent preheating should apply with waste heat from the process because there is no additional cost of energy price.

Experimental Study on Catalytic Pyrolysis of Biomass Pellet

2013 ◽  
Vol 291-294 ◽  
pp. 320-323 ◽  
Author(s):  
Ai Jun Xue ◽  
Ji Hong Pan ◽  
Mao Cheng Tian
Keyword(s):  
Catalytic Pyrolysis ◽  
Test Bench ◽  
Biomass Gasification ◽  
Biomass Pyrolysis ◽  
Corn Straw ◽  
Pyrolysis Products ◽  
Volume Percentage ◽  
Pyrolysis Characteristics ◽  
Pyrolysis Of Biomass ◽  
Biomass Pellet

In the present study, catalytic pyrolysis characteristics of corn straw pellet were studied in biomass pyrolysis test bench. The effect of content of CaO added in biomass pellet on pyrolysis products was investigated. The results showed that: with the increase of CaO content, the yield of tar decreased ,and the yield of char and gas increased. Among gas compositions, the volume percentage of CO、H2、CH4 increased, while the volume percentage of CO2 decrease greatly. The Calorific values of the gas increase distinctly. The results have significant theoretical guidance on the application of biomass pellets in biomass gasification equipments.

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