Skip to main content

TURBINES AND PUMPS

 TURBINES

A turbine is a device that harnesses the kinetic energy of the fluid, such as water, steam, air and combustion of gases. It turns in to the rotational motion of the device itself. This devices are generally used in engine, electrical generations and propulsions of jet systems. Basically there are two types of turbines :- a) Impulse Turbine    b) Reaction Turbine

IMPULSE TURBINE

An Impulse Turbine, as the name indicates, is a turbine which runs by the impulse of  water. In an impulse the water from the dam is made to flow through a pipeline, and then through guide mechanism and finally through the nozzle. In such a process, the entire energy of water is converted into kinetic energy, by passing it through the nozzles; which are kept close through the runners. The water enters the running wheel in the form of a jet, which impinges on the buckets, fixed to the outer periphery of the wheel. 

The jet of water impinges on the buckets with a high velocity, and after flowing over the vanes, leaves with a low velocity; thus imparting energy to the runner. The pressure of water boyh at entering and leaving the vanes, is atmospheric. The common example of impulse turbine is pelton wheel, windmill etc.

REACTION TURBINE

In Reaction Turbine, the water enters the wheel under pressure and flows over the vanes. As the wheels flowing over the vanes, is under pressure, therefore wheel of turbine runs full and maybe be submerged below the tail race and may discharge into the atmosphere. The pressure head of water while flowing over the vanes is converted in to velocity head and is finally reduced to the atmospheric pressure, before leaving the wheel.

The main components of reaction turbine are:- a) Spiral Casing, b) Guide Mechanism, c) Turbine Runner and d) Draft Tube. 

PERFORMANCE OF TURBINE:-

  • Keeping the discharge in constant, the head of water and output may vary. In such cases the speed should be adjusted, so that there is no appreciable change in efficiency.
  • Keeping the head of water and speed constant, the output may vary. In such cases, the discharge of turbine should be adjusted.
  • In turbines working under low heads, the head of water and speed may vary. Although the speed of water is allowed to fluctuate within narrow permissible limits, yet the head may vary upto 50%.
  • Keeping the head of water and discharge constant, the speed may vary by adjusting the load of turbine.

PUMPS

We all know that pump is device that is used to lift water. Basically there are two types of pumps. They are:-  a) Centrifugal Pumps  b) Reciprocating Pump

CENTRIFUGAL PUMP



The pump which raises water from higher level to lower level by action of centrifugal force is called centrifugal pump. It is reverse than that of reaction turbine. In reaction turbine, the water at high pressure, is allowed to enter the casing which gives mechanical energy as its shaft; whereas centrifugal pump, the mechanical energy is fed into the shaft and water enters the impeller which increases the pressure energy of the outgoing fluid. The water enters the vane radially and exerts outside the vane axially.

RECIPROCATING PUMP

A reciprocating pump is called a positive displacement pump, as it discharge a definite quantity of liquid during the displacement of its piston or plunger. A reciprocating pump in its simplest form consist of the following parts as shown in the figure:-

  1. A cylinder C, in which piston P works. The movement of the piston is obtained by connecting rod, which connects the piston and rotating crank.
  2. A suction pipe connecting the source of water and the cylinder.
  3. A delivery pipe, into which the water is discharged from the cylinder.
  4. A suction valve a, which admits the flow of suction pipe into the cylinder.
  5. A delivery valve b, which admits the flow from the cylinder into the delivery pipe. 

PERFORMANCE OF PUMP:-

Sometimes, there is a monor change in the requirement of the head of water or the discharge of the pump from its designed head of water or discharge. In such a case a slight adjustment in the pump is made to suit the new set of conditions. This done either:-
    1. Varying speed of the pump or impeller.
    2. By changing the diameter of the pump impeller.

Labels:
Location: Duliajan, Assam, India

Comments

Post a Comment

Please do not enter any spam comment.

Popular posts from this blog

How to edit grid systems in Etabs

 Okk in the last blog I had discussed about Etabs for beginners. You have got at least some ideas about it. If you have not seen it then click here . But here I am going to discuss how you will edit Grids/Columns in Etabs. As I had said by clicking on "Modify/Show Grid Systems" option a new dialog box appears, their you can edit anything. But you can also do it by different way. On the left side in grid dimensions (plan) you can see that two options are available. One is "Uniform Grid Spacing" and the other is "Custom Grid Spacing". Click on the "Custom Grid Spacing" and you see that Edit Grid Data option is available. Just click on that, and you can edit it as you want by giving the required dimensions in X-axis and Y-axis only. Ok whatever be lets come to the topic. If you have done it like as I have shown earlier then follow those steps. And the one who were new to this blog this is just for that. That's why I underlined with BLUE line an...
Post a Comment
Read more

How to make Staircase in Etabs

 In the last blog I had described about making beams, columns, slabs/roofs in Etabs. But I forgot to tell you how to make staircase. Apology for that. But today in this blog I am going to discuss how to make staircase in Etabs. So before making Staircase first of all delete one side of the slab by single click. But remember one thing in the story side you should have to click "All Stories" so that automatically all slabs will get deleted and required gap and positioning will be appeared.  First click on All Stories After that select one portion of slab   After that go to Edit menu and click on Delete   Then one part of the slab of each story becomes hollow So doing the following steps you can now make the staircase. As for staircase we need hollow section at the top of it, so that it's free to move. In practical field also you can't provide staircase if the roof is covered with slab. Now the main procedure begins for Etabs.  Go to define tab menu and click on Se...
Post a Comment
Read more

WHAT IS PEDESTAL IN FOOTING ?

 During foundation you should always be careful that there is no water present in the excavation pit and the depth should be accurate. So for that you need manwork and labourers to maintain it's accuracy. So before going further for any work just be careful that the depth of foundation is accurate and no error should be made. Because the structure of a building is fully depend upon foundation. And this is general sense that the all the building loads are carried to the foundation i.e., footing.  Before doing any foundation work first of all brick soiling is to be done or sand filling. The building where high rise structures are made, sand filling is done; but the house with ground floor, brick soiling is sufficient. But from where you will get the bricks. Obviously you will have to order or bring it from bricks factory where bricks are made. And after bringing the bricks where you will placed them?  (Actually all these practical knowledge are not taught in the college so ...
Post a Comment
Read more