Weirs and Notches

A notch is generally used to measure the movement and the flow of the water bodies. The water is also a notch but it has been seen that a weir is measured on a large scale. The weir is generally a cut that is given to the notch. It is a cut in the dam so that the excess supply of water can be discharged. When the water flows on the weir or a notch the excess water flow of the dam gets discharged. There are different types of weirs and notches in agriculture engineering which are named rectangular, triangular, stepped, trapezoidal etc. 

Discussion 

“Types of notches and Weirs”

Weirs are of different shapes and sizes as mentioned below. It is generally based on the shape of the opening of the weirs and also according to the shape of the crest.

Based on the Size and Shape of the weir Opening

1. “Rectangular weir”
2. “Triangular weir”
3. “Trapezoidal weir”

Based on Crest and its Shape

1. “Sharp-crested weir”
2. “Broad- crested weir”
3. “Narrow-crested weir”
4. “Ogee-shaped weir”

Uses of  notches and the notches and weirs

If the discussion is about the application of the weirs and notches then it can be said that these are generally included in reservoirs, tanks, or in any device which is used for storing the water and has a passage for the flowing of the water. Similarly, it has also been evaluated that a weir which is a large form of the notch is generally used in the canals and river so that the water flow can be measured. 

Therefore, it can also be said that apart from measuring this two mechanisms are also used for discharging the excess water from the water bodies and channels. If the usage is taken into consideration it can be said that the wieners and the notches helps in regulating the flow of the water.  Various researches conducted in agricultural engineering to evaluate the importance of the weirs and notches, this mechanism plays a great role in saving the excess flow of water in river so that the nearby places and cities can be saved during the time of the flood. The extra supply of the water in the dam can also be discharged. The main purpose of the weirs and notches is to regulate the flow of water bodies and discharge the excess supply of water so that the nearby places can be saved during the time of the flood.

End contraction of weirs and notches

The end contraction of the wires generally means that the canal or the ditch leads so that the opening for the weir can be made even wider. It has been evaluated that when the weir is generally found straight it starts extending to the full width of the water bodies or the channel. This mechanism of the weir is called the end contraction of the weirs and notches. Therefore if the width of the weir is found to be very less than the width of the given channel this mechanism is generally stated as the end contraction with the weirs. 

Basically, it can be said that there is no such difference in both the forms of the notch and a weir except the size. It has been found that the notch is smaller than the weir. It can also be stated that the end contraction depends on the shape and size of the weirs and notches.

Conclusion 

Weirs and notches are generally used in the water body so that the excess supply of the water can be discharged and also for the efficient flowing of the water bodies. It can be concluded that these are very important for the maintenance of water bodies as it plays a very great role in discharging the water bodies as it helps the nearby cities to protect them during the time of the flood. It also plays a very important role in helping to measure the water regulation so that the small and large channels can flow efficiently