Prediction of annual down flow layer thickness in circulating fluidized beds
Summary :
Table of Contents
- Introduction
- Experimental aspects
- Results and discussions
- Estimation of solids down flow film thickness
- Cluster properties
- Modification of Yerushalmi's theory: Effects of acceleration and friction
- Corelation for solids down flow film thickness
- Conclusion
- Notation
- References
Abstract
he solids distribution in circulating fluidized beds (CFB) has been extensively studied because of its importance in design of CFB boilers and reactors. In circulating fluidized bed, normally, the upper region consists of a dilute core surrounded by a relatively dense annulus, with solids down flow near the wall. The literature reports that the solids near the wall move down in the form of film with clusters and variable thickness. Therefore, it is very important to predict solids film thickness near the wall to estimate the heat transfer between a solid suspension in the bed and wall.
In the present work, The experiments were conducted on two laboratory scale CFB units consisting of 0.0508m diameter & 3 m height and 0.1016m diameter & 6m height. Sand (182 µm and 2560 kg//m3) and FCC particles (99 µm and 1600 kg/ m3) were used as bed material. The operating gas velocity and solid circulation rates were in the range of 1-6m/s and 5-125kg/m2-s respectively. The local solids film thickness data were estimated from the experimental data of local solids flux obtained by using U-tube probe. Further, Yersushalmi's [1] homogeneous cluster suspension model was modified by including acceleration and friction effects to characterize clusters. Also, an empirical equation to calculate local solids film thickness was developed. The empirical equation fits quite well with experimental data.
Latest in the category : Physics & chemistry
1
Spectrum of consciousness: Evolution of the spectrum
Term papers | 10/01/2009 | en | .doc | 13 pages
4
Implementation of vector quantization technique in image compression and speech recognition system
Term papers | 09/21/2009 | en | .pdf | 6 pages
5
Analysis of comparative method for association rule mining
Term papers | 09/21/2009 | en | .pdf | 4 pages
Most downloaded in the last 30 days : Physics & chemistry
2
Synthesis and analysis of Ammonium vanadates and determination of water and Vanadium content in Ammonium decavanadate using manganometry
Research papers | 04/25/2009 | en | .doc | 8 pages
From the same author : Physics & chemistry
3
A study on security analysis for selecting appropriate security
Research papers | 05/22/2009 | en | .doc | 79 pages
4
Business community and automation of business processes
Research papers | 05/22/2009 | en | .doc | 36 pages
5
A study on the recruitment and selection process in organizations
Research papers | 05/22/2009 | en | .doc | 34 pages
Change Currency
Our guarantee :
How it works?
Quality guaranteed
Refunds
Secure payment
Who are we ?
