scholarly journals Experimental Investigation on the DPF High-Temperature Filtration Performance under Different Particle Loadings and Particle Deposition Distributions

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1465
Author(s):  
Yong Tong ◽  
Jie Tan ◽  
Zhongwei Meng ◽  
Zhao Chen ◽  
Liuwen Tan
Keyword(s):  
High Temperature ◽  
Carbon Black ◽  
Solid Particle ◽  
Particle Deposition ◽  
Carbon Black Particle ◽  
Filtration Efficiency ◽  
Particle Emission ◽  
Solid Particles ◽  
Particle Loading ◽  
Negative Effects

Based on DPF filtration and regeneration bench, the solid particle emission and high-temperature filtration characteristics of different carbon black particle loadings and particle deposition distributions are studied. The aerosol generator (PAlAS RGB 1000) is used to introduce carbon black particles into the inlet of a DPF, and the NanoMet3 particle meter is used to measure the solid particle concentration at the inlet and outlet of a DPF to obtain the filtration characteristics. Previous studies found that without inlet carbon black particles, there was an obvious solid particle emission peak at the outlet of the deposited DPF during the heating, and the concentration increased by 1–2 orders of magnitude. In this paper, the high-temperature filtration characteristics under steady-state temperature conditions are studied. It is found that a DPF can reduce the range of inlet fluctuating particles, and with the increase of temperature, the proportion of large solid particles in the outlet particles increases, and the size distribution range decreases. Particle loading has positive and negative effects on the DPF filtration, and the DPF has the optimal particle loading, which makes the comprehensive filtration efficiency improve the highest. The deposition transition section can make the deposition particles in the DPF uniform, but the filtration efficiency is reduced.

scholarly journals EFFICIENCY OF HARDENING OF METALLURGICAL EQUIPMENT SPARE PARTS BY HARD ALLOY

2019 ◽  
Vol 61 (12) ◽  
pp. 939-947
Author(s):  
V. А. Bystrov
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Service Life ◽  
Hard Alloy ◽  
Solid Particle ◽  
Thermal Stresses ◽  
Spare Parts ◽  
Solid Particles ◽  
High Temperature Wear ◽  
Hardening Process

Composite  materials  (CM)  are  widely  used  for  hardening  of  wearing parts operating at high temperature wear types. They are based  on  high-melting  hard  alloys,  as  which  are  used  carbides  of  transition  metals  of  IV – VI  groups A  determining  the  physics  of  high-temperature wear. For these purposes baked TiC of TN 20 type on the basis  of (Ti, Mo)C – Ni – Mo is used that has a ring structure preventing the  formation of complex alloyed structures on the bounda ry of solid particle-matrix. Due to the minimal solubility of the sintered hard alloy of  TN 20 type in the alloy-bond, at the interface of solid particle – matrix  practically does not stand out complex structural phases causing embrittlement and growth of residual thermal stresses and strains. It leads  to increased wear resistance and longer service life of hardened parts.  In order to increase the opera ting efficiency of metallurgical units due  to  hardening  of  spare  parts  with  a  composite  material  based  on  sintered hard alloy of the TN 20 type using electroslag surfacing (ESW),  a comprehensive program has been developed to control the efficiency  of hardening parts. In the management of hard alloy surfacing the special  attention  is  given  to  heat  and  high  temperature  wear  resistance  determined  by  the  set  of  CM  properties  of  solid  particles.  Therefore,  maintaining of high mechanical, thermal and energy characteristics of  carbides and decrease of the solubility of solid particles in a CM matrix  at surfacing is a priority for improving efficiency in hardening process  of spare parts. Integrated ESW management program for CM is based  on  effects,  aimed  to  prevent  the  formation  of  complex  alloyed  structures on surface of the solid section of particle-matrix; to reduce thermal stresses and deformations (leading to the cracks formation, chipping and deleting solid particles in abrasive wear) and to improve high  temperature wear resistance. Use of the developed control systems for  hardening  process  of  metallurgical  equipment  wearing  parts  has  significantly  increased  the  service  life  of  spare  parts  and  producti vity  of  the metallurgical units, which ensured a certain economic effect.

Research on Electrical Double Percolation of Carbon Black-Filled Cement-Based Composites

2011 ◽  
Vol 311-313 ◽  
pp. 201-204
Author(s):  
Hong Zhong Ru ◽  
Ran Ran Zhao
Keyword(s):  
Carbon Black ◽  
Cement Paste ◽  
Volume Fraction ◽  
Carbon Black Particle ◽  
Carbon Black Content ◽  
Percolation Behavior ◽  
Key Factor ◽  
Binder Ratio ◽  
Black Particle ◽  
Double Percolation

Electrical conductive carbon black-filled cement-based composites are significant as multifunctional structural materials. Double percolation in carbon black-filled cement-based composites involves both carbon black particle percolation and cement paste percolation, which has great effect on the resistivity of composites. Based on double percolation theory, the influences of sand-binder ratio and carbon black volume fraction on the resistivity of carbon black-filled cement-based composites are investigated. The results show that besides carbon black volume fraction, sand-binder ratio is a key factor affecting double percolation behavior in carbon black-filled cement-based composites. At a fixed carbon black content in overall mortar, with increasing sand-binder ratio, the cement paste percolation though aggregate phase increases due to high obstruction of aggregate but the carbon black particle percolation in cement paste decreases. This is because that the microstructure of aggregate is impenetrable so that the carbon black particles are limited in cement paste, that is, the carbon black content in paste is compacted and large amount of conductive paths are generated by lapped adjacent carbon black particles in paste. The double percolation in the electrical conduction in carbon black-filled cement-based composites is observed when the carbon black volume fraction is 7.5% and sand-binder ratio is 1.4, and its resistivity is only 3200 Ωcm, so that a sand-binder ratio of 1.4 and 7.5% carbon black volume fraction or more are recommended for attaining high conductivity with a compromise between workability and conductivity.

Simulation of Impaction Between Liquid Droplet and Solid Particles Based on SPH Method

2014 ◽  
Author(s):  
Shuai Meng ◽  
Qian Wang ◽  
Rui Yang
Keyword(s):  
Surface Tension ◽  
Solid Particle ◽  
Liquid Droplet ◽  
Particle Interaction ◽  
Solid Particles ◽  
Seed Particle ◽  
Liquid Droplets ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Spray Granulation

The phenomenon of impaction between liquid droplets and solid particles is involved in many scientific problems and engineering applications, such as impaction between sprayed droplet and solid particles in limestone injection desulfurization system and the collision between a droplet of the liquid to be granulated and a seed particle in fluidized bed spray granulation process. There are a lot of factors affected this phenomenon: droplet and particle size, momentum of both liquid droplet and solid particles, materials, surface conditions of the solid particles and so on. However the experimental or numerical researches have been done mostly pay attention to Specific application or process, so the impaction phenomenon has not been through studied, for example how different factors affected the impaction process with its effect on different applications. This paper focuses on the basic issue of interaction between droplet and solid particles. Three main factors were considered: ratio of diameter between the droplet and solid particle, relative velocity and the surface tension (including the contact angle between droplet and solid particle). All the study is based on simulation using SPH (smoothed particle hydrodynamics) method, and the surface tension is simulated by particle-particle interaction.

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