Explain the Need of draft tube in reaction turbine .state the types of draft tube used in it

Explain the Need of draft tube in reaction turbine .state the types of draft tube used in it
by

1 Answer

Answer :

Draft tube is a pipe of gradually increasing diameter which connects the exit of runner of turbine to tail race. In case of reaction turbine , one part of available head is converted into K.E before entry to runner and rest of energy is in the form of pressure energy. This pressure energy is gradually converted into runner, thus the velocity leaving the runner is at high velocity. Draft converts K.E to pressure head . also 1) To decrease the pressure at the runner exit to a value less than atmospheric pressure and thereby increase the effective working head. ii) To recover a part of electric energy into pressure head at the exit of draft tube. This enables easy discharge to atmosphere.

Types of draft tube:

i. Conical draft tube.

ii. Simple elbow draft tube.

iii. Moody spreading draft tube.

iv. Elbow draft tube with circular cross section at inlet and rectangular at outlet.

image

by

Related questions

Explain Construction and working of Francis Turbine with neat sketch.

Description : Explain Construction and working of Francis Turbine with neat sketch.

Last Answer : The main parts of the Francis turbine are: 1) Penstock: It is the large pipe which conveys water from the upstream of the reservoir to the turbine runner. 2) Spiral casing: It is a closed passage ... After doing the work the water is discharge to the trail race through the draft tubes.

Draw and explain performance and operating characteristics curves of a Pelton turbine

Description : Draw and explain performance and operating characteristics curves of a Pelton turbine 

Last Answer : The followings are the important characteristic curves of a turbine : Main Characteristic Curves or Constant Head Curve. ... The speed of the turbine is varied by changing load on the turbine. For each value ... through the turbine as the load varies. Head may or may not kept constant.

Draw sketch of Bourdon tube pressure gauge and state its advantages.

Description : Draw sketch of Bourdon tube pressure gauge and state its advantages.

Last Answer : Advantages:  • These give more accurate results. • Bourdon tube cost low. • Bourdon tube are simple in construction. • They can be modified to give electrical outputs. • They are safe even for high pressure measurement. • Accuracy is high especially at high pressures.

Explain water hammer phenomenon and state the remedies measures to avoid it.

Description : Explain water hammer phenomenon and state the remedies measures to avoid it.

Last Answer : Water hammer phenomenon: commonly occurs when a valve closes suddenly at an end of a pipeline system, and a pressure wave propagates in the pipe. Water hammer (or hydraulic shock) is the momentary increase in ... . caused by the moving water. 7) Use high strength pipes. 8) Close the valve slowly.

Explain Bernoulli’s theorem with neat sketch. State its two important assumptions.

Description : Explain Bernoulli’s theorem with neat sketch. State its two important assumptions.

Last Answer : This theorem states that whenever there is continuous flow of liquid the total energy at every section remains same provided that there is no any addition or loss of energy.  Let us consider ... incompressible. 4. Velocity is uniform over the cross section. 5. The flow is irrotational.

State the need of surge tank in hydroelectric power plant.

Description : State the need of surge tank in hydroelectric power plant.

Last Answer : It is the tank provided in the path of penstock to avoid pulsating discharge at inlet of turbines. To reduce effect of water hammer surge tanks are provided. During flow of ... reservoir to turbine through penstock pressure surges are created to compensate these surges surge tank is provided.

List various minor losses in fluid flow. Explain any one type with sketch and formula.

Description : List various minor losses in fluid flow. Explain any one type with sketch and formula.

Last Answer : List various minor losses a) Sudden expansion of pipe b) Sudden contraction of pipe c) Pipe fittings d) Bend in pipe e) Loss of head at Entry. f) Loss of ... The head loss resulting from pipe expansion may be greatly reduced by introducing gradual pipe transition known as diffuser. 

State any four faults in centrifugal pump and their remedies

Description : State any four faults in centrifugal pump and their remedies

Last Answer : Sr.No Fault remedies 1 Pump fails to start pumping Reprime the pump , Clean the impeller Reduce suction lift , Increase the speed 2 Pump stops working ... Reduce the speed Correct the direction of rotation of impeller Reduce the discharge , Repair affected parts

State the difference between Static head & Manometric head in centrifugal pump.

Description : State the difference between Static head & Manometric head in centrifugal pump.

Last Answer : Static head: The sum of suction head & delivery head is known as static head.  Manometric head: It is the total head that pump is required to develop. This include all losses. This is equal to difference between pressure head at inlet & outlet of pump.

The pressure in the tyres of the four wheeler was measured as 33. State the unit of pressure in this case. Name the device use to measure this pressure.

Description : The pressure in the tyres of the four wheeler was measured as 33. State the unit of pressure in this case. Name the device use to measure this pressure.

Last Answer : The unit of pressure 33 in this case is PSI (Pound per square Inch).  The name of device used to measure is Bourdon Tube Pressure Gauge

Derive equation for discharge through orifice meter with the help of neat sketch.

Description : Derive equation for discharge through orifice meter with the help of neat sketch.

Last Answer : Orifice Meter or orifice Plate: It is a device used for measuring the rate of flow of a fluid through a pipe. It is Cheaper device as compared to venturimeter. It also works on the same ... a distance of about half the diameter of the orifice on the downstream side from the orifice plate. 

Discuss the factors considered for selection of pump

Description : Discuss the factors considered for selection of pump

Last Answer : 1) Pressure: Pump is ued to pressurize the fluid in system according to need of pressure we can select pump as below 2) Speed of pump: if the speed of pump is increased beyond its ... according to application we can choose it by economical aspect cost of pump & its spares should be less.

Draw the layout of hydroelectric power plant and classify the turbines used in it.

Description : Draw the layout of hydroelectric power plant and classify the turbines used in it.

Last Answer : Layout of hydroelectric power plant: Classification of the hydraulic turbines: According to the type of energy available at inlet to the turbine 1)impulse turbine and 2) Reaction turbine ... speed of the turbine 1)low specific speed 2)medium specific speed 3)High specific speed

Compare i) Steady and uniform flow ii) Laminar and turbulent flow

Description : Compare i) Steady and uniform flow ii) Laminar and turbulent flow

Last Answer : Steady flow:- The flow is said to be steady when the flow characteristics, such as velocity, pressure, density and temperature do not change with time. Water flowing through a tap at a constant rate is an ... called as turbulent flow. e.g. The flow of river at the time of flood is turbulent flow.

Draw indicator diagram for reciprocating pump showing the effect of accelerating head and frictional head.

Description : Draw indicator diagram for reciprocating pump showing the effect of accelerating head and frictional head.

Last Answer : Draw indicator diagram for reciprocating pump showing the effect of accelerating head and frictional head.

Write Chezy’s equation for frictional losses and list all the terms involved in it.

Description : Write Chezy’s equation for frictional losses and list all the terms involved in it.

Last Answer : Where; V = velocity of water in pipe,  m = hydraulic mean depth =A/P = d/4  I = loss of head per unit length,  C = Chezy’s constant

Show the difference between hydraulic gradient line & total energy line with the help of suitable diagram.

Description : Show the difference between hydraulic gradient line & total energy line with the help of suitable diagram.

Last Answer : Show the difference between hydraulic gradient line & total energy line with the help of suitable diagram.

Compare water and oil of specific gravity 0.8 on the basis of density & viscosity.

Description : Compare water and oil of specific gravity 0.8 on the basis of density & viscosity.

Last Answer : Here it is not possible to find out viscosity

What is something that is automated that shouldn't be? What is something that isn't that should be?

Description : What is something that is automated that shouldn't be? What is something that isn't that should be?

Last Answer : OMG…those DAMN automated answering devises that companies have. Push this…push that. Makes me boiling mad. Put a human being on the end of that phone!!! Make it that we can talk to a person & give people jobs.

Explain the mechanics of chip formation with neat diagram.

Description : Explain the mechanics of chip formation with neat diagram. 

Last Answer : Mechanics of chip formation: The basic mechanics of forming a chip are the same regardless of the base material. As the cutting tool engages the workpiece, the material directly ahead of ... action of slipping or shearing, which takes place within the crystals and between adjacent crystals.

How to Replace Automatic Transmission Fluid

Description : How to Replace Automatic Transmission Fluid

Last Answer : How to Replace Automatic Transmission Fluid Many cars run on automatic transmission because it is easy to use in city driving. Just because gear changes are automatic, however, maintenance should still be ... , you can easily replace ATF on your automatic transmission car and add years to its life.

How to Refill Brake Fluid

Description : How to Refill Brake Fluid

Last Answer : How to Refill Brake Fluid Driving with low brake fluid is not just bad for your car and damaging for its brakes, but it can be dangerous for you as well. Monitoring your brake fluid is relatively ... a secure place where children won't get it, as it is potentially harmful and dangerous to them.

How to Check Your Windshield Washer Fluid Level

Description : How to Check Your Windshield Washer Fluid Level

Last Answer : How to Check Your Windshield Washer Fluid Level Rain, sleet, or snow will not keep you from driving your car on a daily basis. Dust, pollution, and smoke will not keep you from driving ... mixed with the water to prevent the wiper blades from hardening and causing streaks on the windshield glass.

Best Motorcycle for a novice lady biker?

Description : Best Motorcycle for a novice lady biker?

Last Answer : Yamaha SX 650. It’s light,powerful and simple. Exactly how I like my men XD Have fun!

How can I get my silly little 1990 Ford Ranger to pass it's Gas Evap test?

Description : How can I get my silly little 1990 Ford Ranger to pass it's Gas Evap test?

Last Answer : I meant April. not August…

Is there anything I can do to fix my car myself?

Description : Is there anything I can do to fix my car myself?

Last Answer : What year, make, model? What’s normal mileage you’ve seen? What’re you seeing now? How many miles are on the odometer? When’s the last time you had some kind of scheduled maintenance done?

What is a crank shaft?

Description : What is a crank shaft?

Last Answer : http://en.wikipedia.org/wiki/Crank_shaft

What is a cam shaft?

Description : What is a cam shaft?

Last Answer : http://en.wikipedia.org/wiki/Cam_shaft

What is mechanics?

Description : What is mechanics?

Last Answer : http://en.wikipedia.org/wiki/Mechanics

How To Make Mechanics Hand Cleanser

Description : How To Make Mechanics Hand Cleanser

Last Answer : Grind up a bar or two of your soap 1 c. borax 1-2 t. pure turpentine 1 t. sweet orange essential oil 1 c. ground soap With very clean hands, work the turpentine and essential oil into the borax ... black on the outside. Don't forget to put a nail brush and pumice stone out with the hand cleanser.

What is the use of draft tube?

Description : What is the use of draft tube?

Last Answer : The draft tube is used to regain the kinetic energy of water coming out of reaction turbine. It enables the reaction turbine to be placed over tailrace level.

What Is The Use Of Draft Tube?

Description : What Is The Use Of Draft Tube?

Last Answer : The draft tube is used to regain the kinetic energy of water coming out of reaction turbine. It enables the reaction turbine to be placed over tailrace level.

The depth of the water table at a place is 45 m below the general ground level. To lift water from a deep tube well in such a locality, the type of pump to be installed is (A) Centrifugal pump (B) Reciprocating pump (C) Deep well turbine pump (D) None of these

Description : The depth of the water table at a place is 45 m below the general ground level. To lift water from a  deep tube well in such a locality, the type of pump to be installed is  (A) Centrifugal pump  (B) Reciprocating pump  (C) Deep well turbine pump  (D) None of these 

Last Answer : (C) Deep well turbine pump

Explain the need of compounding. Suggest the method of compounding for reaction steam turbine with justification.

Description : Explain the need of compounding. Suggest the method of compounding for reaction steam turbine with justification.

Last Answer : Need of compounding: ✔The compounding of steam turbine means the methods to reduce the speed of rotor shaft. ✔To increase the thermal efficiency in power plants, high pressure and high ... compounding: i. Velocity compounding ii. Pressure compounding iii. Pressure-Velocity compounding 

Explain reaction turbine in terms of head:

Description : Explain reaction turbine in terms of head:

Last Answer : High head- Francis Medium head- Propeller Low head- Kaplan

Explain the main difference between impulse and reaction turbine.

Description : Explain the main difference between impulse and reaction turbine. 

Last Answer : When the inlet pressure of steam to the turbine is equal to outlet pressure of steam from the turbine the turbine is called the impulse turbine. In this type the heat is added is very less. ... than the inlet pressure of the steam. There is reduction in pressure with the increase in kinetic energy.

The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be (A) 0.4 (B) 0.56 (C) 0.67 (D) 1.67

Description : The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be (A) 0.4 (B) 0.56 (C) 0.67 (D) 1.67

Last Answer : (A) 0.4

With neat sketch describe working of reaction turbine.

Description : With neat sketch describe working of reaction turbine.

Last Answer : Working principle of reaction turbine- -A turbine in which steam pressure decreases gradually while expanding through the moving as well as through the fixed blade is known as reaction turbine. -In pure ... the steam to leave the moving blade as higher velocity than as which it entered.

Difference between Impulse turbine and Reaction turbine.

Description : Difference between Impulse turbine and Reaction turbine.

Last Answer : Impulse turbine Reaction turbine 1. Steam completely expands in nozzle and pressure remains constant during flow through the blade passage.2. Relative velocity of steam passing over blade of impulse ... more space per unit power. 6.The blades are aerofoil & non symmetrical type.

For harnessing low variable water heads, the suitable hydraulic turbine with high percentage of reaction and

Description : For harnessing low variable water heads, the suitable hydraulic turbine with high percentage of reaction and runner adjustable vanes is  (A) Kaplan (B) Francis (C) Pelton (D) Impeller

Last Answer : For harnessing low variable water heads, the suitable hydraulic turbine with high percentage of reaction and runner adjustable vanes is Kaplan 

What are types of steam turbine and why are they popular?

Description : What are types of steam turbine and why are they popular?

Last Answer : Answer: Condensing and non-condensing, Popular because can convert large amounts of heat energy into mechanical work very efficiently.

What Are Two Types Of Clearance In A Turbine?

Description : What Are Two Types Of Clearance In A Turbine?

Last Answer : 1. Radial – clearance at the tips of the rotor and casing. 2. Axial – the foreandaft clearance, at the sides of the rotor and the casing.

What Are Four Types Of Turbine Seals?

Description : What Are Four Types Of Turbine Seals?

Last Answer : 1. Carbon rings fitted in segments around the shaft and held together by garter or retainer springs. 2. Labyrinth mated with shaft serration's or shaft seal strips. 3. Water seals where a shaft ... using woven or soft packing rings that are compressed with a gland to prevent leakage along the shaft.

What are two types of clearance in a turbine?

Description : What are two types of clearance in a turbine?

Last Answer : 1. Radial - clearance at the tips of the rotor and casing. 2. Axial - the fore-and-aft clearance, at the sides of the rotor and the casing.

What are four types of turbine seals?

Description : What are four types of turbine seals?

Last Answer : 1. Carbon rings fitted in segments around the shaft and held together by garter or retainer springs. 2. Labyrinth mated with shaft serration's or shaft seal strips. 3. Water seals where a ... using woven or soft packing rings that are compressed with a gland to prevent leakage along the shaft.

List the types of turbine used in hydro power plant.

Description : List the types of turbine used in hydro power plant.  

Last Answer : Following types of turbine used in hydro power plant:  1.Pelton wheel 2.Francis Turbine 3.Kaplan Turbine 4.Propeller Turbine 

State the term governing of turbine and explain nozzle control governing.

Description : State the term governing of turbine and explain nozzle control governing.

Last Answer : Governing of turbine: The function of governor is to regulate the supply of steam to the turbine so that the speed of rotation shall remain constant at all loads. Nozzle control governing: ... . When the load on the turbine is reduced the supply of steam to a group nozzle is shut off

Explain the term ‘Draft’ related to forging.

Description : Explain the term ‘Draft’ related to forging.

Last Answer : Draft — The necessary taper on the side of a forging to allow removal from the dies; also applies to the die impression. Commonly expressed in degrees as the draft angle.

Explain the construction and working of induced draft cooling tower with neat sketch.

Description : Explain the construction and working of induced draft cooling tower with neat sketch.

Last Answer : Induced draft cooling tower :  Diagram: Construction and working: Cooling towers are employed to cool utility cooling water by direct contact with air. The parts of a cooling tower are ... top pulls the hot air through the fills and cooled water gets collected in the cold water basin.

Explain the principle of working of impulse steam turbine.

Description : Explain the principle of working of impulse steam turbine. 

Last Answer : When steam enters the turbine it suffers a change in direction and momentum, which gives rise to the rotation of the turbine. There will be no drop in pressure in impulse steam turbine.