2006 Fiscal Year Final Research Report Summary
BASIC STUDY ON THE PERFECT PUSH-PULL LOCAL VENTILATION SYSTEM OF TOXIC GAS.
Project/Area Number |
17560163
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Fluid engineering
|
Research Institution | AICHI UNIVERSITY OF TECHNOLOGY |
Principal Investigator |
NAKABAYASHI Koichi AICHI UNIVERSITY OF TECHNOLOGY, FACULTY OF ENGINEERING, PROFESSOR, 工学部, 教授 (90024231)
|
Co-Investigator(Kenkyū-buntansha) |
NAITO Etsuro AICHI UNIVERSITY OF TECHNOLOGY, FACULTY OF ENGINEERING, PROFESSOR, 工学部, 教授 (50074068)
MORINISHI Yohei NAGOYA INSTITUTE OF TECHNOLOGY, GRADUATE SCHOOL, ASSOCIATE PROFESSOR, 大学院工学研究科, 助教授 (40222351)
HATTORI Hiroyuki AICHI UNIVERSITY OF TECHNOLOGY JUNIOR COLLEGE, ASSOCIATE PROFESSOR, 短期大学部, 助教授 (60321030)
|
Project Period (FY) |
2005 – 2006
|
Keywords | JET / SUCTION / CAPTURING LIMIT / LOCAL VENTILATION SYSTEM / PUSH-PULL / TURBULENT FLOW / ENTRAINMENT / ENVIRONMENTAL FLUID MECHANICS |
Research Abstract |
THIS STUDY IS UNDERTAKEN IN ORDER TO ESTABLISH THE PUSH-PULL VENTILATION SYSTEM TO CAPTURE THE POLLUTANTS OR TOXIC GAS OF BUOYANT JET INTO THE PULL HOOD OPENING PERFECTLY AND TO DECREASE THE ENERGY USED TO DRIVE MACHINES INSTALLED IN THE VENTILATION SYSTEM AS LITTLE AS POSSIBLE. FIRSTLY IN THIS YEAR, NOZZLE GEOMETRIES WERE IMPROVED TO PROVIDE THE PLANE AIR JET ISSUING THROUGH THE RECTANGULAR NOZZLE TWO-DIMENSIONALLY AND UNIFORMLY. NEXT, THE LIMIT OF AIR FLOW RATE INDUCED THROUGH THE BOUNDARIES OF THE TWO-DIMENSIONAL TURBULENT PUSH-PULL FLOW FIELD TO CAPTURE THE POLLUTANTS OR TOXIC GAS IN THE BUOYANT JET FOR THE VARIOUS AIR JET FLOW RATES ISSUING FROM THE NOZZLE PERFECTLY WERE OBTAINED USING THE FLOW VISUALIZATION TECHNIQUES. ON THE TURBULENCE STRUCTURE OF THE TWO-DIMENSIONAL PUSH-PULL FLOW, MEAN VELOCITY AND FLUCTUATING COMPONENTS IN THE FLOW WERE MEASURED AT VARIOUS LOCATIONS FROM THE NOZZLE TO THE EXHAUST HOOD BY I-TYPE HOT WIRE ANEMOMETER. THE DEVELOPMENT OF THE MEAN VELOCITY AND TURB
… More
ULENCE INTENSITY PROFILES WAS INVESTIGATED UNDER THE CONSTANT SPEED OF AIR JET ISSUING FROM THE NOZZLE FOR TWO CASES UNDER AND ABOVE THE LIMIT OF INDUCTION AIR FLOW RATE, RESPECTIVELY. AND THE INFLUENCE ON SUCTION OF THE AIR SPEED PULLED INTO THE EXHAUST HOOD WAS CONSIDERED AT THE VARIOUS LOCATIONS IN THE TWO-DIMENSIONAL TURBULENT PUSH-PULL FLOW FIELD. THE RESULTS OBTAINED ARE AS FOLLOWS. THERE ARE DISTINCT DIFFERENCES BETWEEN THE DEVELOPING JET REGION NEAR THE NOZZLE AND THE SUCTION REGION NEAR THE EXHAUST HOOD. IN THE DEVELOPING JET REGION, MEAN VELOCITY PROFILE DEVELOPS FROM THE TOP-HAT PROFILE TO THE GAUSSIAN CHARACTERISTIC DISTRIBUTION, AND RELATIVE TURBULENCE INTENSITY INCREASES DOWNSTREAM AND THE LOCATION OF THE PEAK VALUE CHANGES FROM THE HALF-VELOCITY POINT TO 0.75 TIMES THE HALF-VELOCITY POINT. THE RESULT AGREES WITH THE CONVENTIONAL RESULT OF THE PLANE JET EXHAUSTING FROM THE NOZZLE INTO QUIESCENT SURROUNDINGS. IN THE SUCTION REGION, ON THE OTHER HAND, MEAN VELOCITY PROFILE SPREADS FROM THE GAUSSIAN CHARACTERISTIC PROFILE IN THE INNER ZONE INSIDE THE HALF-VELOCITY POINT TO THE VELOCITY DISTRIBUTION OF THE EXTERNAL IRROTATIONAL FLOW FIELD CAUSED BY THE SUCTION. THE TURBULENCE INTENSITY SHOWS FLAT DISTRIBUTION IN THE INNER ZONE, AND DECREASES GRADUALLY TOWARDS THE EXTERNAL FLOW FIELD. Less
|
Research Products
(6 results)