We were discussing the basicÂ difference between orifice and mouthpiece,Â classification of orifices and mouthpieces,Â advantages and disadvantages of orifices,Â hydraulic coefficients,Â experimental process to determine the hydraulic coefficients,Â flow through fully submerged orifice,Â flow through partially submerged orifice, time of emptying a tank through an orifice fitted at its bottom and also time of emptying a hemispherical tank through an orifice in the subject of fluid mechanics in our recent posts.Â

Now we will go ahead to find out the method to determine the time of emptying a circular horizontal tank through an orifice at its bottom with the help of this post.Â

Let us consider we have one circular horizontal tank filled with a liquid up to a height of H1. Let us consider that one orifice is fixed at the bottom of the circular horizontal. We are interested here to determine the time taken in emptying the circular horizontal tank.Â
Let us consider the following data from above figure.Â

R = Radius of the circular horizontal tank
L = Length of the circular horizontal tank
a = Area of the orifice
H1= Initial height of the liquid in the circular horizontal tank
H2= Final height of the liquid in the circular horizontal tank Â
T = Time taken in emptying the tank from H1Â to H2.Â

Time taken in emptying the circular horizontal tank from H1Â to H2Â will be given by following formula as mentioned here.Â

Let us determine the time emptying the circular horizontal tank, H2Â will be zero.Â

This is the expression for the time emptying the circular horizontal tank fitted with orifice at its bottom.Â

Now we will go ahead to find out the flow through an external cylindrical mouthpiece, in the subject of fluid mechanics, in our next post.Â

Do you have any suggestions? Please write in comment box.Â

### Reference:

Fluid mechanics, By R. K. Bansal