How do you calculate the efficiency of a water wheel?
The most efficient energy transfer occurs when the wheel speed is at 93% of the water speed. For our example, the spouting velocity is 11.35 feet per second. So 93% of that is around 10 feet per second, which is the same as 600 feet-per-minute. You divide this by the working circumference per revolution.
What makes a waterwheel efficient?
This type of water wheel uses gravity to improve output as well as the water itself, thus overshot waterwheels are much more efficient than undershot designs as almost all of the water and its weight is being used to produce output power.
What size water wheel do I need?
In other words, the water is moving as fast as it would if it had fallen 1.55 feet. Your wheel should then be at least 4.65 feet to 9.3 feet in diameter (E.g.: 3 x 1.55 = 4.65 or 6 x 1.55 = 9.3). Whenever possible, make the wheel as large as you can.
How do you calculate water power?
If you don’t mind equations the easiest way to explain how much power you could generate is to look at the equation for calculating hydropower:
- P = m x g x Hnet x η
- Hnet = Hgross x 0.9 = 2.5 x 0.9 = 2.25 m.
- 3 m3/s = 3,000 litres per second.
- Power (W) = m x g x Hnet x η = 3,000 x 9.81 x 2.25 x 0.751 = 49,729 W = 49.7 kW.
How do you calculate power output efficiency?
Efficiency = useful power out ÷ total power in It can be written as a number between 0 and 1 or as a %. For example, an efficiency of 0.25 is the same as an efficiency of 25%. Because some energy is always wasted from every device, efficiency should always be less than 1 or less than 100%.
What are the disadvantages of a water wheel?
Disadvantages of water wheel:
- They are heavy and have a large space requirement, as well as there are losses with overshot wheels due to the height and suspension.
- The rotational speed should be as low as possible to avoid fast emptying of the scoops due to greater centrifugal forces.
How do you calculate efficiency difference?
So if your company’s standard labor hours for a particular project is 70 and the actual amount of time worked is 82, you would divide 70 x 82 and then multiply the answer by hundred, giving you 85% efficiency.
What is the maximum efficiency of an overshot water wheel?
The results showed that maximum efficiency of overshot and undershot water wheels was around 85%, while that of breastshot water wheels ranged from 75% to 80%, depending on inflow configuration.
How much does the water depth affect the efficiency of the wheel?
With the new wheel, a 1 m range in the inlet water depth has little effect on efficiency. During a spate, the water level at the tailrace may be above the lowest part of the wheel.
Why undershot waterwheel is recommended to increase electrification ratio?
The undershot waterwheel is recommended to increase electrification ratio in remote areas of Indonesia due to its simple shape, which results in higher efficiency under low head conditions than other turbines.
What is the H/L ratio of an undershot waterwheel?
An h/L ratio of 1 produces greater power than ratios of 0.5, 0.75 or 1.5. The resulting efficiency with an h/L ratio of 1 is 31.52 %, while with 0.5 it is 22.75 %, with 0.75 it is 29.44 % and with 1.5 it is 26.55 %. Thus, an h/L ratio of 1 is recommended for designing undershot waterwheel turbines.