Fundamental Research on Air mixed water flow in Pipe line of sewage system
| Project/Area Number |
60460163
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Hydraulic engineering
|
|---|
| Research Institution | Toyo University |
|---|
Principal Investigator |
KUNIHIRO Oginara Professor of Toyo University, 工学部, 教授 (60058071)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SHUZOU Tanaka Lectures of Toyo University, 工学部, 講師 (40139043)
|
|---|
| Project Period (FY) |
1985 – 1987
|
| Project Status |
Completed (Fiscal Year 1987)
|
| Budget Amount *help |
¥3,900,000 (Direct Cost: ¥3,900,000)
Fiscal Year 1987: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1986: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1985: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
|---|
| Keywords | Air mixed flow / Sewage pipe line / スラグ流 / 層状流 / プライシング現象 / 下水管渠内の流れ / 気泡流 |
|---|
| Research Abstract |
There are many flow patterns of Air mexed water flow in long pipe line of sewage system, The wwater depth of flow becomes higher when water flows form upstream side to down stream side, because the water flow which is accelerated at upstream side and has high speed velocity and it loses its velocity by the resistant force as asear force acting on the wall surface of pipe line. So the separated flow as observed at upstream side and the slug flow is in down stream dise.
When both raates of discharge of water and air become larger, the resistance force also becomes larger especially at down stream side. This makes the inclination of pressure gradient becomes greater, and finally it reaches the limit value, the water flows rapidly with high speed velocity.
This phenomenon is cooled as priming phenomenon in pipe line which arises by periodical motion. This critical condition can be determined in this model pipe line, but there is some difficult matters to apply thiss critical condition to actual fields sewage pipe line vecause on the sinilitude conditions.
The relations between air bubble and water are same in model pipe line and fields one. This means that the air separation velocity from water is same in both pipe line, so the time of separation is lesser in model test than fields one. And velocity of water flow is higher and intensity of turbulence is stronger in fields condition, so it takes long time to separate the air.
Therefore the similitude low of Froude is applied to this phenomenon, there is a possibility that the different water flow patterns can be observed in fields pipe line in the flowing condition which is determined by model test under the Froude similitude law. This research work must be continued to make the similitude of mixed flow and also to make investigate the phenomena in high speed flow such as the regulating pipe line of dam.
|
Report
(2 results)
Research Products
(5 results)
