1994 Fiscal Year Final Research Report Summary
Production of fine grain limestone by means of focusing and rounding water jets
| Project/Area Number |
05555281
|
|---|
| Research Category |
Grant-in-Aid for Developmental Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
資源開発工学
|
|---|
| Research Institution | Kumamoto University |
|---|
Principal Investigator |
SUGAWARA Katsuhiko Kumamoto University Faculty of Engineering, Professor, 工学部, 教授 (60109668)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NAKAYAMA Tomoharu Kumamoto University Faculty of Engineering, Research Associate, 工学部, 助手 (70207950)
HONDA Itsuro Kumamoto University Faculty of Engineering, Lecturer, 工学部, 講師 (00229254)
OBARA Yuzo Kumamoto University Faculty of Engineering, Associate Professor, 工学部, 助教授 (50135315)
OHBA Hideki Kumamoto University Faculty of Engineering, Professor, 工学部, 教授 (20040412)
|
|---|
| Project Period (FY) |
1993 – 1994
|
| Keywords | Water jet / Abrasive jet / Fragmentation / Erosion / Coanda nozzle / Rock cutting / Water jet mill |
|---|
| Research Abstract |
In order to make clear the applicability of water jet and abrasive jet of focusing and/or rounding to the fragmentation of limestone, the experimental study has been performed and the fundamental data have been presented for the future design of water jet mill. The present experimental study on the possibility of water jet mill consists of four parts as follows :
1. Estimation of incident velocity of water jets by means of impact force measurement.
A practical method to evaluate the structure of water jets impinging onto the rock surface has been presented for the clarification of the fracture mechanism of rock. The impact force that is the resultant force imposed upon a plain-target by water jet impinging normally has been analyzed to estimate the incident velocity and the apparenet density of cylindrical water jets.
2. Erosion characteristics of rock by water jet impingement.
A theory is presented which is applicable to the analysis of erosion process in fragmentation and cutting of rock by a relatively low speed water jet impinging normally onto a rock surface. Both nontraversing and traversing cases are considered.
3. Fragmentation performance of abrasive-water jet.
Fine grain rocks have been accelerated by cylindrical water jet and impinged against a solid target. The fragmentation performance of fine grain rocks has been analyzed as well as the erosion profile of solid targets : aluminium, mild steel, hard metal, alumina and zirconium.
4. Internal flow of coanda nozzle and effect on dispersion of cohesive powders.
Coanda nozzle studied in this work is classified as a jet pump with a shape resembling the Laval nozzle. Three-dimensional mean flow has been measured by a single inclined hot-wire anemometer, and it has been clarified that Reynolds stress plays an important roll in dispersing cohesive powders is much greater than the shear stress.
|
Research Products
(27 results)
