Thermodynamics Lab Manual PDF

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ME-232 THERMODYNAMICS LAB

DEPARTMENT OF MECHANICAL ENGINEERING

ME 232: THERMODYNAMICS LAB (0,1)

Table Of Contents

Experiments: 1 Introduction Introduction about the lab, experiments and the equipment 2 Layout of Steam Power Plant To draw the layout of the steam power plant and study the main characteristics of the system. 3 Steam Boiler To study the starting procedure of steam boiler. 4 Relationship of Steam Temperature and Pressure To investigate the relationship between pressure and temperature of saturated steam. 5 Dryness Fraction To find out the dryness fraction of steam by using separating and throttling calorimeter.

6 Fault finding on Boiler Demonstration Unit To carry out fault finding on Boiler control demonstration unit. 7 Flow through a Convergent Nozzle To investigate the flow of steam through a convergent Nozzle. 8 Flow through a Convergent/Divergent Nozzle To investigate the flow of steam through convergent/divergent nozzle and to plot the pressure variation along its length. 9 Single Cylinder Steam Engine To determine the brake power of a single cylinder steam engine with varying load. 10 PV Diagram of a Steam Engine To trace the PV diagram of a piston side and piston rod side with the help of indicator unit. 11 Study of the Steam Turbine Study of operational procedure and determination of steam flow rate of a steam turbine.

12 Study of the Air-Water-Steam Heat Exchanger To study the heat exchanger and to plot the temperature difference curves for a variety of flow conditions. 13 Air-Water-Steam Heat Exchanger To determine the mean temperature difference between two mediums in both contra and parallel flow.

ME-232 THERMODYNAMICS LAB EXPERIMENT # 1:

Layout of Steam Power Plant

DEPARTMENT OF MECHANICAL ENGINEERING

EXPERIMENT # 1:

Layout of Steam Power Plant

Objective To draw the layout of the steam power plant and study the main characteristics of the system.

Description of apparatus 1.

BOILER:i.

Specifications:-

It is a fully automatic gas fired steam boiler capable of an evaporation rate of 320 kg / hr and with a maximum working pressure of 10.3 bars gauge. ii.

Type:-

This boiler is a vertical fire tube type. iii.

Description:-

It contains a centrally mounted semi forced draught burner firing vertically downward. The boiler is fully lagged and protected by an enameled steel jacket and is furnished with:a) Two safety valves. b) steam stop valve, c) steam pressure gauge d) water level gauge e) blow down valve f) two feed water non return valves g) Feed water pump.

Blower

Water Column

Water Level Gauge

Control Panel

Feed Water

The feed water pump consists of an electric feed pump controlled by an electric water level probe system incorporating low water level alarm and lockout.

Feed Water Pump

The boiler mounted control panel contains the electrical circuitry for fully automatic on-off control of the feed pump from the water level control system, and contains fully automatic on-off control of the burner from a steam pressure control through an interlocked air, ignition, fuel and flame failure sequence controller.

2.

Separating And Throttling Calorimeter

This instrument is fitted at the front of water tank set. This is used for measurement of the quality of steam from the boiler. The equipment is provided with steam pressure gauge, manometer and two temperature thermocouples.

Throttling Calorimeter Separating Calorimeter

Condenser Mercury Manometer

3.

Water Tank Set This equipment acts as a soft water reservoir. Condensate from turbine is returned to this tank. Also the fresh water is first softened by the water softener plant and water treatment plant and then stored in the tank. The ball float valve and supply isolating valve control the make up water level at 200 liters capacity allowing a condensate return of 150 liters. The additional instrumentation for boiler and super heater is also mounted on the tank, .The water feed pump and water treatment plant are also fitted on the water tank set.

Water Storage Tank Boiler Instrumentation Super Heater Instrumentation

Separating and Throttling Calorimeter Water Treatment Plant

Water Softener Plant

Gas meter for Super Heater

Gas Meter for Boiler

4.

Additional Instrumentation For Boiler And Super heater

These instrumentation units include additional instrumentation required to carry out a comprehensive experimental investigation of boiler and super heater performance as well as determination of their efficiencies. These additional instruments are: a. b. c. d. e. 5.

Feed water / gas meter. Fuel flow transducers. Multi-point temperature indicator and thermocouple, for air, feed water, fuel, steam and flue temperature. CO2 absorption indicator. Flue draught manometer

Super heater

It is a fully automatic gas fired super heater rated to give a final steam temperature of 235oC and designed for operation with installed boiler. The super heater comprises of: a. b.

A continuous steam coil with inlet and outlet headers. A semi forced draught gas burner firing horizontally in to a combustion chamber and complete with flame failure control.

Super Heater

The super heater is fully insulated and furnished with a safety valve and drain valve. The control panel contains the electrical circuitry for fully automatic on-off control of the gas burner interlocked through the temperature, pressure, and steam coil over temperature and flame failure detector.

6.

Feed Water Softener Set:-

It comprises of a ion exchange water softener designed to treat water of 200 ppm hardness continuously for eight hours or water of 400ppm hardness continuously for four hours between regeneration and arranged for manual control of the regeneration cycle. It comprises of. a. b. c. d. e. f. g.

Softener vessel. Salt Storage tank. Water meter. Isolating Valve. Bypass Valve. Water sampling point. Feed water additive dosing plant.

Feed Water Softener Set

7.

Steam Turbine And Condenser Set

The steam turbine and condenser set comprises of three main assemblies turbine and condenser base plate, condensate collecting tank and overhead control panel. The turbine base plate sub assembly consists of mild steel fabricated steel plate on which are mounted a turbine. Dynamometer, surface condenser, condenser vacuum pump condensate tank drain pump and inter connecting pipe work. The turbine is a single stage impulse type fitted with stainless steel blades. Manually operated valves on the turbine casing control steam inlet nozzles. The turbine housing consists of two castings bolted together. A large diameter turbine shaft is used which is bearing mounted and provided with a self-lubricating system with carbon ring seals. A constant speed control governor and over speed trip are also fitted to the turbine. The turbine shaft is directly coupled with a flexible coupling to 5 kW dc dynamometer. The dynamometer is mounted in reunions with the torque being measured by a load cell system. Dynamometer field is controlled by variable supply from the overhead control unit. The dynamometer output being dissipated in a load bank. Exhaust from the turbine is discharged into a surface condenser designed to produce correct vacuum conditions at the turbine. Then the exhaust is supplied with appropriate flow of cooling water to make condensate water. The condensate is extracted from the condenser by the electrically operated condenser vacuum pump, which is matched to operate at the condenser vacuum conditions and discharge the condensate into the condensate collecting tank. A small electrically driven condensate tank drain pump is used to drain condensate from the condensate tank. The condensate can be returned to the boiler or exhausted to a drain.

The condensate collecting tank is mounted on four legs and is designed to stand at the end of the turbine base frame; the tank contains baffles to damp out any turbulence. The tank also contains two level switches which are fitted into the tank with a difference in height between them corresponding to set weight of condensate. These level switches are used to start and stop an electrical timer fitted on the overhead control panel. Thus the time taken for a given amount of condensate to be collected is known and the steam flow rate is calculated. The tank can be drained by the automatic use of the condensate tank drain pump or by the use of manually controlled valve. Fitted to the overhead frame are two control panels, one control panel contains the dynamometer control system and electrical indicators, the other panel contains pressure gauges for the system. The maximum output of the turbine is 5 kW when the turbine is supplied with steam at 8.6 bars final super heater steam temperature of 235oC and exhaust conditions of –0.69 bar. The maximum operated speed is 3000 rpm and maximum steam consumption at full load is 276 kg/hr.

Condenser

Steam Turbine

8.

Nozzle Test Rig

Nozzle test rig is used for experiments in investigation of flow through different types of nozzles. The required nozzle can be fitted in a thick insulated cylinder. The rig is equipped with pressure and temperature gauges for measurement of property of steam at different points. A probe is provided by which the steam properties can be measured at different places with in the nozzle. The throttling calorimeter fitted with the test rig is used to determine steam quality at different times during the experimental investigations Inlet Pressure Gauge

Line Pressure Gauge

Outlet Pressure Gauge

Nozzle Throat Pressure Gauge

Nozzle Inlet Chest

. 9.

Cooling Tower

The glass fiber reinforced cooling tower is designed to be compatible with steam turbine condenser unit and steam-air-water heat exchanger when working in an ambient temperature of 15oC. Water on to the tower 31oC, water off 21oC. Cooling tower consists of a honeycombed filled with induced draught and water, air inlet grills and bosses for pipe work connections. A cooling water recirculation pump capable of passing the volume of water required by the condenser / cooling tower is also fitted with the system. 10.

Steam-Air-Water Heat Exchanger

This apparatus is to be used for the study of heat transfer phenomenon between steam-air, steamwater, hot water-air and hot water cold-water substances in parallel and contra parallel flow. The desired combination can be achieved by setting the selection of valve to the required position. The rate of water and airflows can be measured by flow measuring instruments fitted with the equipment. The temperature at different point of the heat exchanger can be measured from the dial gauges or the digital readout unit while proper press switch is pressed.

11.

Steam Engine

The engine is a single cylinder, horizontally mounted, double acting steam valve system. Fitted on the crankshaft of the engine are the two valve drive eccentrics, the governor drive pulley and a large flywheel with a water cooled dynamometer brake drum. Fitted around the brake drum is a brake band on which are fitted wooden brake blocks. The brake band can be adjusted by means of an adjusting screw mounted at the top of the brake. A torque arm to a 0-50 kg spring balance, which is damped by means of an oil dashpot, connects the brake. The Meyers valve gear fitted to the cylinder head enables the valve cut off point to be varied by use of a small hand wheel fitted to the threaded shaft which projects from the cylinder head. A calibrated scale at the side of the wheel indicates the amount of cut off selected. Mounted on the top of the cylinder is a Pickering type engine governor, which is driven by a belt from the governor drive pulley on the engine crankshaft. On the side of the cylinder are two connections to a selector valve on which is mounted the engine indicator diagram unit. The cord hook of the indicator drive cord is attached to an actuator arm operated by the crosshead. Cups are mounted on the engine to ensure complete engine lubrication during operation. A 0-16 bar pressure gauge is provided for steam pressure indication and is connected to the steam chest. A 0-300 rpm tachometer is mounted on the end of the crankshaft to provide a speed indication. The engine is capable of producing 3 kW. The maximum speed is 210 rpm and maximum steam consumption of 204 kg/hr.

Lubricating Oil

Governor Steam Engine

12. Boiler Control Demonstration Unit:-

1. INTRODUCTION:The Cussons P7665 Boiler Control Demonstration Unit has been designed to demonstrate clearly and simply a range of boiler control sequences relating to oil or gas fired boilers. Since steam pressure is „simulated‟ the whole functioning of a boiler may be studied in a relatively safe situation. The Demonstration Unit can act as a valuable teaching aid for the training of boiler operating personnel in the diagnosis of boiler system faults which may occur in practice. Water Level Controllers

Boiler

Blower

Boiler Control Penal

Burner

Water Tank

Feed Water Pump

ME-232 THERMODYNAMICS LAB EXPERIMENT # 2:

Steam Boiler

(Steam Boiler) DEPARTMENT OF MECHANICAL ENGINEERING

EXPERIMENT # 2:

Steam Boiler

Objective To study the starting procedure of steam boiler. THEORY: a) Introduction:A steam generator or a steam boiler is, usually, a closed vessel made of steel. Its function is to transfer the heat produced by the combustion of fuel (solid, liquid or gaseous) to water, and ultimately to generate steam. b) Important Terms of Steam Boilers:Though there are many terms used in steam boilers, yet the following are important: 1. Boiler Shell:- It is made up of steel plates bent into cylindrical form and riveted or welded together. The ends of shell are are closed by means of end plates. A boiler shell should have sufficient capacity to contain water and steam. 2. Combustion Chamber:- It is the space, generally below the boiler shell, meant for burning fuel in order to produce steam from the water contained in the shell. 3. Grate:- It is the platform, in the combustion chamber, upon fuel is burnt. The grate, generally, consist of cast iron bars which are spread apart so that air (required for combustion) can pass through them. The area of grate, over which the fire takes place, is called grate surface. 4. Furnace:- It is the space, above the grate and bellow the boiler shell, in which the fuel is actually burnt. The furnace is also called fire Box. 5. Heating Surface:- It is that part of boiler surface, which is exposed to the fire (or hot gases from the fire). 6. Mountings:- These are fittings which are mounted on the boiler for its proper functioning. They include water level indicator, pressure gauge, safety valve etc. It may be noted that a boiler cannot function safely without the mountings. 7. Accessories:- These are the devices, which form an integral part of a boiler, but are not mounted on it. They include super heater, economizer, feed water pump etc. It may be noted that the accessories help in controlling and running the boiler efficiently. c) Classification of Steam Boilers:Though there are many classifications of boilers, yet the following are important.

1. According to the contents in the tube. The steam boilers, according to the contents in the tube may be classified as: (a). Fire tube or smoke tube boiler

(b). Water tube boiler.

In Fire tube steam boiler, The flames and hot gases, produced by the combustion of fuel pass through the tube which are surrounded by water. In Water tube steam boilers, the water is contained inside the tubes (called water tubes) which are surrounded by flames and hot gases from outside. 2. According to the position of the furnace:- The steam boilers, according to the position of furnace are classified as: (a). Internally fired boilers

(b). Externally fired boilers

In Internally fired steam boilers, the furnace is located inside the boiler shell. Most of the fire tube steam boilers are internally fired. In externally fires steam boilers, the furnace is arranged underneath in a brick-work setting. Water tube steam boilers are always externally fired. 3. According to the axis of shell. The steam boilers, according to the axis of the shell, may be classified as: (a). Vertical Boilers

(b). Horizontal boilers

In Vertical steam boilers, the axis of the shell is vertical. In Horizontal boilers, the axis of the shell is horizontal. 4. According to the number of tubes. The steam boilers, according to the number of tubes, may be classified as: (a). Single tube steam boiler

(b). Multitubular Boilers

5. According to the method of circulation of water and steam. The steam boilers, according to the method of circulation of water and steam, may be classified as: (a). Natural circulation boilers

(b). Forced circulation boilers

In Natural circulation boilers, the circulation of water is by natural convection currents, Which are setup during the heating of water. In Forced circulation boilers, there is a forced circulation of water by a centrifugal pump driven by some external power.

Description of Apparatus 12.

BOILER:iv.

Specifications:-

It is a fully automatic gas fired steam boiler capable of an evaporation rate of 320 kg / hr and with a maximum working pressure of 10.3 bars gauge. i.

Type:-

This boiler is a vertical fire tube type. ii.

Description:-

It contains a centrally mounted semi forced draught burner firing vertically downward. The boiler is fully lagged and protected by an enameled steel jacket and is furnished with:h) two safety valves. i) steam stop valve, j) steam pressure gauge k) water level gauge l) blow down valve m) two feed water non return valves n) Feed water pump.

Blower

Water Column

Water Level Gauge

Control Panel

Feed Water Pump

The feed water pump consists of an electric feed pump controlled by an electric water level probe system incorporating low water level alarm and lockout.

Feed Water Pump

The boiler mounted control panel contains the electrical circuitry for fully automatic on-off control of the feed pump from the water level control system, and contains fully automatic on-off control of the burner from a steam pressure control through an interlocked air, ignition, fuel and flame failure sequence controller.

Procedure

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33.

Switch on power to water supply pump and open all valves in water feed circuit. Close valve 3 water to heat exchanger. Close valve 57 water to vacuum pump. Close valve 4 water to steam engine. Close valve 5 water Open valve 6 water to softener plant. Open valve 7 water tank inlet valve. Close valve 28 water tank drain valve Close valve 19 gas. Close valve 29 gas. Open valve 8 water tank outlet valve. Close valve 27 drain. Open valve 9 boiler water inlet valve. Close valve 17 boiler blow down. Close valve 23 drain. Close valve 24 drain. Close valve 18 steam stop valve. Open valve 11 water column isolation valve. Open valve 12 water column isolation valve....