three gorges dam

BASIC KNOWLEDGE OF MATHEMATIC

The Amount of Power Produces

Annual electric energy production depends on the available water supply. In some installations the water flow rate can vary by a factor of 10:1 over the course of a year.

The formula is:

P = ρhrgk

Where:

Ρ = Power in watts

ρ = Density of water (~1000 kg/m³)

h = Height in meters

r = Flow rate in cubic meters per second

g = Acceleration due to gravity of 9.8 m/s²

k = Coefficient of efficiency ranging from 0 to 1

(Efficiency is often higher (that is, closer to 1) with larger and more modern turbines.)

Estimation of Water Demand

The amount of water demand depends on the population of the country.

Since China has huge population, so the estimate of water demand is very high.

The formulas to estimate the water supply are:

i) Average Daily Demand;

q = Q / (p x 365 days)

Where:

q = Average daily demand in litre per capita per day

Q = Annual water demand in litre

p = Persons or capita for population

ii) Maximum Daily Demand;

= 180 % x Average Daily Demand

BASIC KNOWLEDGE OF ENGINEERING

The Biggest Flood Control

The three gorges dam is the biggest water conservancy project in the world.

Its reserved flood control capacity can help cut flood peak by 27,000 - 33,000 m3/s.

The flood control standard of the middle and lower reaches of the Yangtze, especially the Jingjiang Section, will be largely upgraded from the present level of preventing under-10-year floods to that of preventing 100-year floods.

Its can prevents of 15 millions and 1.5 hectares of farmland in the Jianghan Plain from flood threats, and devastating plagues of massive death.