Overview of Low Speed Surface Aerator Chaipattana towards Performance Enhancement and Development

of a Stand Alone Solar Water Wheel

Suravut Snidvongs(1)(2), Jongjit Hirunlabh(1), Joseph Khedari(2)

Faculty of Engineering, Bangkok Thonburi University, Thailand. airscan_t@yahoo.com (1)

Faculty of Technology and Innovation, Bangkok Thonburi University, Thailand. (2)

The Fourth National, and Second International Symposium

July 23, 2016. 8.00 am – 18.00 pm. At Building 14th

Bangkok Thonburi University

AbstractThe researchers review types of water aerator in The Kingdom of

Thailand and also in the world. Water Wheel Low Speed Floating Mechanical Surface Aerator Chaipattana, Model RX-2, was the most popular in Kingdom of Thailand. Next, the paper describes the idea towards the development and performance enhancement of a Stand Alone Solar Water Wheel Low Speed Surface Aerator Chaipattana RX-2-3 without battery, reduced power consumption and increased oxygen dissolved in water.

Water Wheel Low Speed Surface Aerator Chaipattana

The Water Wheel Low Speed Floating Mechanical Surface Aerator, or Chaipattana Aerator, is an invention devised at the behest of His Majesty the King for use in the treatment of polluted water generated by residential and industrial communities. This device has multiple uses, including aeration propulsion and mixture by agitation. It can be installed as a stationary or mobile unit. Altogether, nine models have been made but the second one, RX-2, which was patented by His Majesty the King, is the most appropriate for use in treating polluted water.

Aeration methodsWater aerations was any procedure by which oxygen is

added to water. This being the only criterion, there are a variety of ways to aerate water. There are two broad areas, surface aeration and subsurface aeration.

1. Surface Aerators1.1. Low Speed1.2. High Speed2. Subsurface Aerators

1. Surface aerator

1.1. Water Fountains RX-91.2. Floating Surface Aerators (High Speed) RX-71.3. Paddle Wheel Aerators (High Speed) RX-61.4. Water Bucker Aerators (Low Speed) RX-2

Water Fountains RX-9

Floating Surface Aerators RX-7

Paddle Wheel Aerators RX-6

Water Wheel Aerator RX-2

2. Subsurface aerator

2.1. Jet Aerator RX-52.2. Coarse Bubble Aerator RX-12.3. Fine Bubble Aerator RX-32.4. Venturi Aerator RX-42.5. Bio Filter Aerator RX-8

Jet Aerator RX-5

Coarse Bubble Aerator RX-1

Fine Bubble Aerator RX-3

Venturi Aerator RX-4

Bio Filter Aerator RX-8

Oxygen Transfer Efficiency Each Aerator Types

Chaipattana Low Speed Surface Aerator

4 Models of ChaipattanaWater Wheel Aerator

Model A (RX-2-1) Water spraying buckets are rotated by the transmitting power system, using both roller chain and chain sprocket, together with 1:50 reduction gear attached to a two-horsepower electric motor at 0.9 kgO2hphr-1 (1.21 kgO2kWhr-1).

Model B (RX-2-2) Water spraying buckets are rotated by the transmitting power system using 1:300, two-horsepower electric reduction gear motor, driving on one side at 1.2 kgO2hphr-1 (1.61 kgO2kWhr-1), they have similar operations but different driving power and propellers. Model C Similar in feature to Model A, but different in application in that it is not

stationary but mobile, this model is used in case of no accessible electric power in the water source. It is driven by gasoline engine and the direction is controlled by an attendant.

Model D: Water spraying buckets are rotated by 1:50 reduction gear motor, together with 1:6 reduction spur gear, two-horsepower electric motor.

Performance enhancement and development of Model RX-2-3 Aerator

In this research the researchers outline the main ideas toward performance enhancement Water Wheel Low Speed Floating Mechanical Surface Aerator, Model RX-2-2 for a standalone system without battery, reduce power consumption and increase oxygen dissolved in water, RX-2-3.

This aerator has the same feature as RX-2-2, the different is the wheel turn in opposite direction as Contra Rotation. It reduces the torque transfer to the fuselage. This causes all power transfer to the water bucket makes it reduce power. The researchers also optimize the holes size and pattern. These allows water

bucket to drive water in a circle and stir it in smaller droplet so it mixes with air from which the oxygen can be better fused. When the dispersed water falls down again, air bubbles emerge, causes an oxygen evacuation.

Chaipattana Low Speed Surface Aerator RX-2-2, and RX-2-3

RX-2-3 This aerator used induction motor 400 W (1/2 HP) at 1,420 RPM with gear ratio 1:450 to make it turns 3 revolution per minute. RX-2-3 could direct install with 300 W x 2 PV panels without battery and could operates daily.

RX-2-2 This aerator used induction motor 1,500 W (1.5 HP) at 3,000 RPM with chain, sprocket, pulley, and rubber belt gear ratio 1:600 to make it turns 5 revolution per minute. RX-2-2 could not direct install with 300 W x 8 PV panels with battery and step up inverter. It could operates daily.

Contra RotationAdvantage of Contra Rotation1. Energy savings between 6-20% more efficient in producing thrust for a given horsepower.2. Contra Rotating wheels eliminate the gyroscopic effects that exist when operating with a single wheel.3. The power desired was greater than a single wheel could handle.4. Contra Rotating wheel significantly reduce the maximum torque that goes into the fuselage of the system. With a single wheel system the torque that goes into turning the wheel also reacts out against the motor mounts and the fuselage of the water wheel, so if the motor is generating 5 N.m of torque to turn the wheel, the motor is also trying to rotate the fuselage with this same 5 N.m of torque. Whereas, with a Contra Rotating System the torque is divided by the gear ratio of the gearbox, so if the Drive is using a gearbox with a 10:1 gear ratio, then the torque into the fuselage is only 0.5 N.m.

Summary

Holes size and pattern, speed of Water Wheel, and flow rate has effect on power consumption of Water Wheel Aerator. If optimized it could reduce power consumption and improve dissolved oxygen in water. Contra Rotation could reduce fatigue in fuselage and transfer most of power to drive water wheel. RX-2-3 could use induction motor 400 W (1/2 hp) 1,420 RPM with gear ration 1:450 at water bucker speed 3 revolution per minute. PV panels 300 W x 2 without battery. It is expected to operate daily at high oxygen transfer rate. This model is expected to face wider distribution due to its’ high efficiency and low cost.