M. Shiraziul Islam
IWM DIvision, BARI, Gazipur
M. Anower Hossain
IWM DIvision, BARI, Gazipur
M. Atique Ullah
M. Abdullah
IWM DIvision, BARI, Gazipur
A flow diversion device was designed, fabricated and tested in the IWM division of BARI. It divided the pump flow of 9.02 l/s first into two flow rates, each of which was, again, divided in to two flow rates. The discharge of the pump was bifurcated into two equal flows. When each of these smaller flows was allowed to pass through the next diversion sequence, it was split into two flows to pass through 2.54cm, diameter pipes. Thus, initial flow was finally split in to four flows. The device split pump flow (9.02 l/s) first exactly into two (4.51 l/s each0 flows. However, a little variation among the flow rated (2.23 & 2.27 l/s and 2.33 & 2.18 l/s) was observed after the second split of each 4.51 l/s flow. The device is capable of delivering water to 4 pieces of crop fields simultaneously thus providing irrigation facilities to more farmers at a time. Furtherm, due to small flow rates, there is a little possibility of soil eroson and uprooting of tender plants. Present price of the device is Tk. 3000/- but it is fabricated on a large scale, the price will come down to only Tk. 1500.00.
Flow diversion device, design, fabrication, testing
Central farm, BARI, GAzipur
Crop-Soil-Water Management
To design and fabricate a flow diversion device with priming facility for shallow tube well irrigation
In the design of the device, the pump capacity was considered 10 l/s. Two flow equations: the continuity equation i. e.,
Q= AV
And the Bernouli’s energy equation
V12/2g + p1/w + Z1=V22/2g + p2/w + Z2
were used in the design. The continuity equation was used mainly for estimating velocity through the pipes and the Bernouli’s equation for equating the energy at different desired positions of the device. It was assumed that the device would be connected with the pump horizontally so that the water, after entering the device flows out horizontally at some designed lateral angle with the axes of the pipes.
The device consists of 7.62 cmx2.54 cm mild steel reducers, 6 pipes-2 of 5.08 cm diameter and 4 of 2.54 cm diameter, one 5.08 cm priming port with a cap and flanges and gaskets.
Testing of the device
The device was tested to know the flow diversion situations in the pipes. Initially, a 2.5 hp engine coupled with 14 l/s capacity pump was set to test the performance of the device. The device was connected to the outlet of the pump. The discharge of the pump was controlled by the revolutions per minute (rpm) of the engine. The discharges through 7.62, 5.08 and 2.54 cm pipes were recorded. The volumetric measurements of water were made with times to calculate the flow rates.
BARI Annual Research Report 2002-2003
The device provides an opportunity to divide a larger pump flow rate into smaller ones making irrigation suitable for low water requiring crops like onion, garlic and other spices and non-spices crops. Due to bifurcation of the pump flow into 4 flows, four farmers can divert pump water to their lands simultaneously. Further, due to smaller flows, reduced soil erosion and damage to tender plants can be possible.
Report/Proceedings