Water lifting vane pump- the ‘HYDRO-GEN’

Consolation Awards


Imli Toshi
City: Mokokchung
State: Nagaland

Imli Toshi (22), hails from Mokokchung, Nagaland and has done his BSc and also obtained a Post Graduate diploma in Computer applications. Brought up with a farming background, he has got hands on experience. Currently unemployed, he has always had a keen interest in machineries and automobiles and his other innovations include an innovative egg-boiler and hot-water filter.

Genesis

The idea of this innovative pump came into his mind while he was washing his car at home. For this he needed to go to the water fall just near his house for filling up his bucket with water every time. Then he thought of the possibility of diverting the water to his car-washing place with a certain height. These thoughts resulted in the development of this innovative low discharge energy pump. Imli Toshi developed a hydro-powered pump for irrigation which is a novel combination of a Vane pump and spiral bladed water turbine. The vane pump offers the best combined characteristics of sustained high level performance, energy efficiency, trouble-free operation and low maintenance cost and Imli Toshi has managed to drive such a pump using the natural flow of river/ dam water.

The innovation is a water pumping device which works without the help of electricity or any fossil fuels (petrol, diesel) to power the motion. This pump is a horizontally submerged centrifugal pump. The blades capture kinetic energy of water flow and transmit it to the main shaft which is coupled to the pump. The pump is made up of two sections such as pump (vane) and a spiral blade (screw type). It is submerged in flowing water and the linear velocity of the water is used to drive the spiral blade shaft that is coupled to the pump and this provides the rotational velocity of the pump. This pump can lift water up to a height of one meter.

The parts involved in the pump are as follows:

Casing (made up of polyvinyl chloride), Supporter (two numbers), Shaft with spiral blades, Ball (used as a bearing), Thrust bearing for supporting the shaft (one number), Three levers for supporting the shaft, A circular wooden block, Three flat blades, Three springs, Screw (twelve pieces), bolt and nut (one pair) and Delivery pipe etc.

Working principle

The pump is completely submerged in the natural flow of water. Five sets of spiral blades, which are at 35 degree angles, are attached to the shaft. This shaft starts to rotate anticlockwise as the water passes through it. The rotational movement of the turbine shaft helps to rotate the rotor of the vane pump. The vanes are placed in a slotted rotor or impeller by helical spring. The slotted rotor or impeller is eccentrically supported in a cycloid cam. The rotor is located close to the wall of the cam so that a crescent shaped cavity is formed. The rotor is sealed into the cam by two side plates. As the impeller rotates and water enters the pump, the centrifugal force, hydraulic pressure and the spring force push the vanes to the walls of the housing. The tight seal among the vanes, rotor, and cam and side plate is the key to the good suction characteristics common to the Vane pumping principle. The housing and cam force fluid into the pumping chamber through holes in the cam. Water enters the pockets created by the vanes, rotor, cam, and side plate. As the impeller continues around, the vanes sweep the water to the opposite side of the crescent where it is squeezed through discharge holes of the cam as the vane approaches the point of the crescent. Fluid then exits the discharge port with high outlet pressure and velocity with respect to the inlet pressure of the water.

Unlike normal cases, where the direction of the water is perpendicular to the axis of the impeller, in this device the water flow is in line with the main inlet shaft which has a series of spiral vanes. The pump is placed axially in the direction of flow in river or channel to capture high-speed water flow. Axial momentum is converted into rotary momentum in the centrifugal pumping unit and pumping action happens due to this rotation of rotary impeller mounted on the same shaft.

Cost-effective, eco-friendly …

This compact device can develop a good vacuum and does not require very high water velocity to run the turbine and thus it can be used in small channels or rivers. Continuous water supply and uniform load distribution on the motor throughout the cycle due to balanced system are some other salient features. This pump costs about Rs.800 which is much lower than the investment required for conventional pumps. As no electricity is required the operating costs are minimized. Whereas in a conventional pump set used for irrigation in the agricultural fields, at least around Rs.300/- per day is required.

Installation costs are also eliminated as this pump just needs to be set in the water channel one night before the required day, as discharge rate is very slow. The maintenance cost of this pump is much less and there is no problem of rusting. Further it is light weight and hence portable and easy to handle.

Comparison with other existing technology

Vane pump consist of a rotor disc having a number of slots into which fit sliding blades or vanes. But in this innovative pump the working principle is the same as that of the vane pump but the rotor or impeller is made of wood rather than of iron or plastic. In the existing vane pump the pump is driven by motors of different capacity depending upon the type of requirement of pumping. But in this turbine no electric power and motor is used to drive the pump. The design of the blade can be compared with the Archimedes screw conveyor. Screw conveyors are one of the oldest and simplest methods for moving bulk materials and consist primarily of a conveyor screw rotating in a stationary trough.

But in this innovative pump the screw or spiral blades are used to drive the pumps which work as an electric motor.

Test Report

The first model of the pump was tested in NERWRI (North Eastern Regional Water Research Institute). When the water speed was one meter per minute(3.3ft/minute) the speed of the shaft was 5 r.p.m. and the discharge from the vane pump was noted as one litre per 40 seconds (90 litres per hour) at one metre head and one m/s velocity of water. It operated at low cut-in of two feet per second.

Of great rural relevance…

This pump is cheap and runs on its own. It is a low cost, self generating water pump which can be used to pump water from a feed water channel to the crop field. This could also be used in remote mountain areas where it can be used just to raise water from a river on to adjacent areas. This rotating unit can also be used for generating power or used for any other secondary agrarian mechanical operation.