Military Institute of Science & Technology (MIST),
Dhaka
Department of Mechanical Engineering
ME-304
Power Plant Sessional
LEVEL-3, TERM-I
Contact Hr: 3 Credit: 1.5
Name of the Experiments
1. Study of Boiler
2. Performance Test of Cooling Tower
3. Study of Steam Turbine
4. Study of Gas Turbine (Jet) Engine
5. Determination of Carbon Residue of a Given Fuel
6. Proximate Analysis of Coal
7. Study and Calibration of Pressure Gauge by Dead Weight Tester
8. Determination of Calorific value of Gaseous Fuel by Gas Calorimeter
EXPERIMENT NO – 1
Name of experiment: Study of Industrial Boiler
Objectives
1. Introduction of different components of steam power plant
2. To study the functions of boiler mountings and accessories.
Steam power plant
Generally, steam power plant is called as thermal power plant. The steam power plant can
perform two purposes. To generate electricity only and to generate electricity along with
production of steam for process heating. Steam power plant works on Rankine Cycle. Working
fluid is steam and water.
The main components of cycle are
1. Boiler: Boiler is used to produce steam. Heat energy produced by coal is used to produce
steam. Water is allowed to heat until it goes into vapor state. Vapor is sent to the turbine.
2. Turbine: Turbine produces the work. Work produced is used to run the generator. The
enthalpies at the enter and exit of the turbine are different. Then Vapor is sent into the
condenser.
3. Condenser: The vapor is condensed to water in the condenser and sent into the pump.
4. Feed pump: Pump send the water again into the Boiler and the cycle repeats again.
Figure: Layout of a steam power plant.
Figure: Cochran Boiler
Cochran Boiler
It is a multi-tubular vertical fire tube boiler having a number of horizontal fire tubes. It is the
modification of a simple vertical boiler where the heating surface has been increased by means of
a number of fire tubes.
It is consisted of:
Shell: It is hemispherical on the top, where space is provided for steam.
Grate: It is placed at the bottom of the furnace where coal is burnt.
Fire box (furnace): It is also dome-shaped like the shell so that the gases can be deflected back
till they are passed out through the flue pipe to the combustion chamber.
Flue pipe: It is a short passage connecting the fire box with the combustion chamber.
Fire tubes: A number of horizontal fire tubes are provided, thereby the heating surface is
increased.
Combustion chamber: It is lined with fire bricks on the side of the shell to prevent overheating
of the boiler. Hot gases enter the fire tubes from the flue pipe through the combustion chamber.
Chimney: It is provided for the exit of the flue gases to the atmosphere from the smoke box.
Manhole: It is provided for inspection and repair of the interior of the boiler shell.
Boiler Mountings
Boiler mountings are the machine components that are mounted over the body of the boiler itself
for the safety of the boiler and for complete control of the process of steam generation. Various
boiler mountings are as under:
1. Pressure gauge
2. Water Level Indicator
3. Fusible plug
4. Safety Valve
5. Steam stop valve
6. Feed check valve
7. Blow-off cock
8. Man and Mud hole
Boiler Accessories
Boiler accessories are those components which are installed either inside or outside the boiler to
increase the efficiency of the plant and to help in the proper working of the plant. Various boiler
accessories are:
1. Air Preheater
2. Economizer
3. Super-heater
4. Feed Pump
Air Preheater
Air preheater is a waste heat recovery device. Air goes through it to the way of the furnace where
it is heated utilizing the heat of exhaust gases. The function of air pre-heater is to increase the
temperature of air before entering the furnace. It is generally placed after the economizer; so, the
flue gases pass through the economizer and then to the air preheater. An air-preheater consists of
plates or tubes with hot gases on one side and air on the other.
Economizer
It is a device in which the waste heat of the flue gases is utilized for heating the feed water to
recover some of the heat being carried over by exhaust gases. This heat is used to raise the
temperature of feed water supplied to the boiler.
Fig: Economizer
Super heater
The function of super heater is to increase the temperature of the steam above its saturation point
to superheat the steam generated by boiler. Super heaters are heat exchangers in which heat is
transferred to the saturated steam to increase its temperature.
Fig: Super heater
Classification of boilers
According to contents in the tube:
a)
Fire tube boiler: In fire tube boilers, the flue gases pass through the tube and water
surround them. Vertical tubular, Lancashire, Cochran, Cornish, Locomotive fire box, Scotch
marine etc. are some fire tube boilers.
b)
Water tube boiler: In water tube boiler, water flows inside the tubes and the hot flue gases
flow outside the tubes. Babcock and Wilcox boiler, Stirling boiler, La-mont boiler, Benson boiler,
Loeffler boiler etc are some of water tube boilers.
EXPERIMENT NO – 2
Name of experiment: Performance Test of Cooling Tower
Air flow circuit
Under the action of the fan, air is driven upward through the wet packing. It will be seen that the
change of dry bulb temperature is smaller than the change of wet bulb temperature, and that at air
outlet there is little difference between wet and dry bulb temperatures. This indicates that the air
leaving is almost saturated, i.e. relative humidity -100%. This increase in the moisture content of
the air is due to the conversion of water into steam and the ‘latent heat’ for this account for most
of the cooling effect.
•
If the cooling load is now switched off and the unit allowed stabilizing, it will be found
that the water will leave the basin close to the wet bulb temperature of the air entering.
According to the local atmosphere conditions, this can be several degrees below the
incoming air (dry bulb) temperature.
Air flow rate
The orifice at the top of the cooling tower (an example of an obstruction flow meter) has been
calibrated by the manufacturer to measure mass flow rate of dry air as a function of differential
pressure across the orifice and specific volume of the moist air mixture exiting the tower. This
relationship is:
𝑚̇𝑎 = 0.0137√
𝑥
𝑥
= 0.0137√
𝑣𝐵
(1 + 𝜔𝐵 )𝑣𝑎𝐵
Where,
𝑚̇𝑎 = Dry air mass flow rate (𝑘𝑔𝑠 −1 )
𝑥 = Orifice differential (𝑚𝑚𝐻2 𝑂)
𝑣𝐵 = Specific volume of steam and air mixture leaving top of column (𝑚3 𝑘𝑔−1 )
𝜔𝐵 = Specific humidity of air leaving top of the column (𝑘𝑔𝑘𝑔−1)
Water flow circuit
•
The warm water enters the top of the tower and is fed into troughs from which it flows via
notches onto the packing. The troughs are designed to distribute the water uniformly over
the packing with minimum splashing.
•
The packing have an easily wetted surface and the water spreads over this to expose a large
surface to the air stream.
•
The cooled water falls from the lowest packing into the basin and may then be pumped to
a process requiring cooling (or in the Bench Top Cooling Tower, to the simulated load in
the load tank).
•
Due to evaporation from the water, “make-up” must be supplied to maintain the quantity
of water in the cooling system. The falling level in the load tank may be observed over a
period of time.
•
Droplets of water (resulting from splashing, etc.) may become entrained in the air stream
and then lost from the system. This loss does not contribute to the cooling, but must be
made good by “make-up”. To minimize this loss, a “droplet arrester”, or “eliminator” is
fitted at the tower outlet. This component causes droplets to coalesce, forming drops which
are too large to be entrained and these fall beck into the packing.
Water flow rate
Water flow rate is measured by flow meter& direct measurement in gm/sec can be done.
Locations of the 6 temperature readings to be taken when using the system:
T1: Dry bulb temperature of air entering base of column.
T2: Wet bulb temperature of air entering base of column.
T3: Dry bulb temperature of air at exit from column.
T4: Wet bulb temperature of air at exit from column.
T5: Water temperature on entering column.
T6: Water temperature on leaving column.
Cooling Tower Terms:
Cooling Range: The difference between the water temperatures at entry to end exit from the tower.
Cooling Load: The rate at which heat is removed from the water. This may be expressed in KW,
Btu/h or Cal/h.
Make-up: The quantity of fresh water which must be supplied to the water circuit to make good
the losses due to evaporation and other causes.
Drift or carry over: Droplets of water which are entrained by the air stream leaving the tower.
Packaging or fill: The material over which the water flows as it falls through the tower, so that a
large surface area in present to the air steam.
Approach to Wet Blub: The difference between the temperature of the water leaving the tower
and the wet blub temperature of the air entering.
Drain Down: Water deliberately removed from the water system to prevent the excessive
concentration of dissolved solids due to evaporation and sludge due to impurities from the
atmosphere.
Basic Principles of Heat Transfer
Assuming that the water is hotter than the air, it will be cooled:
1) By radiation: This effect is likely to be very small at normal conditions and may be
neglected.
2) By conduction and convection: This will depend on the temperature difference, the
surface area , air velocity, etc.
3) By evaporation:
This is by far the most important effect. Cooling takes place as
molecules of o𝐻2 O diffuse from the surface into the surrounding air. These molecules are
than replaced by others from the liquid (evaporation) and the energy required for this is
taken from the remaining liquid.
Evaporation from the wet surface
The rate of evaporation from a wet surface into surrounding air is determined by the difference
between the vapor pressure at the liquid surface, i.e., The saturation pressure corresponding with
the surface temperature, and vapor pressure in the surrounding air. The latter is determined by the
total pressure of the air and its absolute humidity.
In an enclosed space, evaporation can continue until vapor pressure are equal, ie. Until the air is
saturated and at the same temperature as the surface. However, unsaturated air is constantly
circulated, the wet surface will reach an equilibrium temperature at which the cooling effect due
to the evaporation is equal to the heat transfer to the liquid by conduction and convection from the
air, which under the conditions, will be at a higher temperature.
The equilibrium reached by the surface under adiabatic conditions. i.e., In the absence of external
heat gains or losses, is the “wet bulb temperature”, well known in connection with hygrometry. In
cooling tower of infinite size and with an adequate air flow, the water leaving will be at the wet
bulb temperature of the incoming air. For this reason, the between the temperature of the water
leaving a cooling tower and the local wet bulb temperature is an indication of the effectiveness of
the cooling tower. The “Approach to Wet Bulb” is one of the important parameters in the testing,
specification, design and selection of cooling towers. Conditions within a cooling tower packing
are complex due to changing air temperature, humidity and water temperature as the two fluids
pass through the changing air temperature, humidity and water temperature as the two fluids pass
through the tower- usually in a contra flow fashion.
Student Name:
Student ID:
DATA SHEET:
Inlet Air Properties
Outlet Air Properties
Water Properties
Air
Flow
Rate
(kg/s)
Obs.
Dry
bulb
(℃)
Wet
bulb
(℃)
relative
humidity
RH(%)
Specific
Humidity
𝜔(g/kg of
Dry air)
Specific
Volume
𝑉𝐵 (𝑚3 /
𝑘𝑔))
Dry
bulb
(℃)
1
2
Wet
bulb
(℃)
relative
humidity
RH(%)
Specific
Humidity
𝜔(g/kg of
Dry air)
Specific
Volume
𝑉𝐵 (𝑚3 /
𝑘𝑔)
Inlet
Temp
(℃)
Outlet
Temp
(℃)
Flow
Rate
(kg/s)
1
2
3
4
5
6
7
8
9
10
CALCULATION SHEET:
Observation
Theoretical cooling Range (𝑅𝑡ℎ )
Actual Cooling Range (𝑅𝑎 )
Cooling Efficiency (𝜂)
Change in Specific Humidity ( Δ𝜔)
Makeup Water
% Make up Water
Inlet Air Enthalpy ( ℎ𝑎 𝑖𝑛 )
Outlet air enthalpy (ℎ𝑎 𝑜𝑢𝑡 )
Change in Heat content of Air
Inlet water enthalpy (ℎ𝑤 𝑖𝑛 )
Outlet water enthalpy (ℎ𝑤 𝑜𝑢𝑡 )
Change in Heat content of water
Unaccounted Heat
3
4
5
6
7
8
9
10
EXPERIMENT NO – 3
Name of experiment: Study of Steam Turbine
Components of a Miniature Steam Turbine Plant
All the components are mounted on a self-supporting framework of a similar design to that used
for the Steam Bench Apparatus.
1. Boiler Unit
Figure 1: Twin burner steam boiler
2. Steam Turbine
Figure 2: Steam turbine and condenser
3. Condenser Unit
Figure 3: Condenser
4. Instrumentation
Figure 4: Instrumentation panel
Theory
The function of the steam turbine is to convert the heat energy contained in the steam into
rotational energy at the shaft. The steam expands through the turbine nozzle, doing work on the
turbine heel. Steam admission is controlled by the steam inlet control valve.
Impulse turbines change the direction of flow of a high velocity fluid or gas jet. The resulting
impulse spins the turbine and leaves the fluid flow with diminished kinetic energy. There is no
pressure change of the fluid or gas in the turbine rotor blades (the moving blades), as in the case
of a steam or gas turbine, all the pressure drop takes place in the stationary blades (nozzles).
Before reaching the turbine, the fluid’s pressure head is changed to velocity head by accelerating
the fluid with the rotor. Newton’s second law describes the transfer of energy for impulse
turbines.
U1
U2
Vw2
Φ
VΦ
r2
β Va2
Vf2
Vr1
U
Va1=Vw1
Vf1=0
Figure 5: Inlet and Exit velocity triangles for an impulse turbine.
Figure 5 shows the velocity triangles that can be used to calculate the basic performance of the
turbine stage. Gas exits the stationary turbine nozzle guide vanes at absolute velocity Va1. The
rotor rotates at velocity U. Relative to the rotor, the velocity of the gas as it impinges on the
rotor entrance is Vr1. The gas is turned by the rotor and exits, relative to the rotor, at velocity Vr2.
However, in absolute terms the rotor exit velocity is Va2. The velocity triangles are constructed
using these various velocity vectors. Velocity triangles can be constructed at any section through
the blading (for example: hub, tip, midsection and so on) but are usually shown at the mean
stage radius. Mean performance for the stage can be calculated from the velocity triangles, at
this radius, using the Euler equation: Typical velocity triangles for a single turbine stage
Whence:
where:
Specific enthalpy drop across stage
Turbine entry total 9or stagnation) temperature
Turbine rotor peripheral velocity
change in whirl velocity
The turbine pressure ratio is a function of
and the turbine efficiency.
1. Heat balance for 1 m3 of fuel
Energy supplied (CV of 1 m3 of fuel) Ecv kJ/m3
Energy lost to surroundings and unburned fuel El
Energy to change water to steam Est
Energy
gases
Energy to dry gases Edg
carried
away
by flue
Energy to moisture of combustion Ewg
Figure 6: Heat Balance for fuel.
Ecv
This value of kJ/m3 is the energy supplied by a m3 of the fuel and is obtained from the data sheet,
or may be calculated using the results of the chemical analysis of the fuel together with calorific
value date for the fuel elements.
Est
The energy to change the feed water into steam is the enthalpy of steam generated, less the
enthalpy of the feed water
Edg+Ewg
The energy given to the flue gases is obtained from the gas flow rate, the mean specific heat of
the flue gases, the mean temperature of the flue gases and the surrounding air.
Mean specific heat includes water content.
El
The energy lost is calculated from
2. Boiler efficiency
It is defined as the ratio between energy grained by fluid and total energy input to the system.
Boiler Efficiency =
Total energy input is given by fuel flow rate multiplied by calorific value of fuel.
i.e. Total energy =
Energy gained by fluid =
Where ms is steam flow rate,
hs is enthalpy of steam at the boiler output conditions and
hfw is enthalpy of feed water at temperature tfw.
3. Equivalent Evaporation:
The evaporative capacity of a boiler is normally quoted as the rate in kg/hr at which steam is
generated. For a given firing condition the amount of steam generated depends on the enthalpy
change from feed water to steam conditions. Since the enthalpy of the feed water depends on
its temperature and similarly that of the steam depends on the steam pressure and temperature.
Equivalent Evaporative F and A 100°C =
Where ms is mass of steam generated,
hs is enthalpy of steam at the operating conditions
hfw is enthalpy of feed water at operating conditions and h
is enthalpy of evaporation at 100°C and 1 bar.
4. Some other data Calculations
4.1
Steam consumption
4.2
4.3
Electric power =
Specific steam consumption
4.4
Energy supplied to turbine
For steam condition 176°C and 4.6 bar gauge, the enthalpy is 2800 kJ/kg (using enthalpy-entropy
diagram, Figure).
4.5
Energy supplied to the nozzle =
For steam condition 151°C and 5.6 bar gauge, the enthalpy is 2750 kJ/kg (using enthalpy- entropy
diagram, Figure).
4.6
Energy at exhaust = (𝑒𝑛𝑡ℎ𝑎𝑙𝑝𝑦 𝑎𝑡 𝑒𝑥ℎ𝑎𝑢𝑠𝑡 × 𝑠𝑡𝑒𝑎𝑚 𝑐𝑜𝑛𝑠𝑢𝑚𝑝𝑡i𝑜𝑛)
For steam condition 80°C and 1 bar gauge, the enthalpy is 2645 kJ/kg (using enthalpy-entropy
diagram, Figure).
4.7
Energy drop through throttle valve
4.8
4.9
4.10
Energy to dynamometer=
Energy to friction/losses in turbine
=(𝑒𝑛𝑒𝑟𝑔𝑦 𝑑𝑟𝑜𝑝 𝑡ℎ𝑟𝑜𝑢𝑔ℎ 𝑡𝑢𝑟𝑏i𝑛𝑒 − 𝑒𝑛𝑒𝑟𝑔𝑦 𝑡𝑜 𝑑𝑦𝑛𝑎𝑚𝑜𝑚𝑒𝑡𝑒𝑟)
𝑘𝐽
=2.5 − 0.048 = 2.452 𝑚𝑖𝑛
4.11
Energy to cooling water
= 𝑚𝑎𝑠𝑠 ƒ𝑙𝑜𝑤 𝑜ƒ 𝑐𝑜𝑜𝑙i𝑛𝑔 𝑤𝑎𝑡𝑒𝑟 × 4.18 × 𝑡𝑒𝑚𝑝 𝑟i𝑠𝑒 𝑜ƒ 𝑐𝑜𝑜𝑙i𝑛𝑔 𝑤𝑎𝑡𝑒𝑟
= 0.9 × 4.18 × (30 − 18) = 45.14 𝑘𝐽/𝑚i𝑛
4.12 Energy to condensate
= 𝑚𝑎𝑠𝑠 ƒ𝑙𝑜𝑤 𝑜ƒ 𝑠𝑡𝑒𝑎𝑚 × 4.18 × 𝑐𝑜𝑛𝑑𝑒𝑛𝑠𝑎𝑡𝑒 𝑡𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒
=0.042 × 4.18 × 63 = 6.32 𝑘𝐽/𝑚i𝑛
4.13 Energy to exhaust radiation
= 𝑒𝑛𝑒𝑟𝑔𝑦 𝑎𝑡 𝑒𝑥ℎ𝑎𝑢𝑠𝑡 − (𝑒𝑛𝑒𝑟𝑔y 𝑡𝑜 𝑐𝑜𝑜𝑙i𝑛𝑔 𝑤𝑎𝑡𝑒𝑟 + 𝑒𝑛𝑒𝑟𝑔𝑦 𝑡𝑜 𝑐𝑜𝑛𝑑𝑒𝑛𝑠𝑎𝑡𝑒)
=63.5 − (45.14 + 6.32) = 12.04 𝑘𝐽/𝑚i𝑛
4.14 Isentropic enthalpy drop
= 𝑒𝑛𝑒𝑟𝑔𝑦 𝑠𝑢𝑝𝑝𝑙i𝑒𝑑 𝑡𝑜 𝑛𝑜𝑧𝑧𝑙𝑒 − (i𝑠𝑒𝑛𝑡𝑟𝑜𝑝i𝑐 𝑒𝑥ℎ𝑎𝑢𝑠𝑡 𝑒𝑛𝑡ℎ𝑎𝑙𝑝𝑦 ×
𝑠𝑡𝑒𝑎𝑚 𝑐𝑜𝑛𝑠𝑢𝑚𝑝𝑡i𝑜𝑛)
=66 − (2645 × 0.024) = 2.52 𝑘𝐽/𝑚i𝑛
4.15 Rankine Energy Supplied
= 𝑒𝑛𝑒𝑟𝑔𝑦 𝑠𝑢𝑝𝑝𝑙i𝑒𝑑 𝑡𝑜 𝑡ℎ𝑒 𝑛𝑜𝑧𝑧𝑙𝑒 − 𝑒𝑛𝑒𝑟𝑔𝑦 𝑡𝑜 𝑐𝑜𝑛𝑑𝑒𝑛𝑠𝑎𝑡𝑒
=66 − 6.32 = 59.68 𝑘𝐽/𝑚i𝑛
4.16 Electrical Conversion Efficiency
4.17
Isentropic Conversion Efficiency
4.18
Rankine Efficiency
Operation
1. Pre-Start Procedure
a)
The boiler feed water tank should be filled with ‘boiled’ or rain water to minimize
the build up of scale in the system. A suitable water supply should be connected to the
cooling system of the condenser and the gas supply and burner fitted should be checked.
b)
The boiler ‘Stem outlet valve’ should be in the open position. This is to allow air
to be discharged freely when the Boiler is later filled with water.
c)
Using the feed water pump filled the boiler until water shows mid way on the
water gauge.
d)
Continue to fill the Boiler with water until the height indicated in the water gauge
glass is approximately one-half of the total height.
e)
Close Boiler steam valve, i.e. turn fully clockwise.
f)
Select “Switch 1” on the load bank.
g)
Place the “condensate” collection beaker in position on the lower table.
2. Preliminary Boiler Checks
a)
Gently pull back the burner assembly from the boiler vessel. The burner
arrangement can now be examined. Check that the Flame Failure thermocouple and the
ignition electrodes have not moved during the transportation process of the equipment.
b)
Ensure that the Flame Failure thermocouple is positioned over the burner slot
and approximately 1/8” from the burner surface. This is to ensure that the thermocouple
is directly over the flame.
c)
Ensure that the Ignition Electrode is positioned as shown with the “spark gap”
approximately 1/8” from the burner slot. This is to ensure that as the fuel mixture emits
from the burner slot, the “spark” will ignite the fuel mixture and ignite the burner.
d)
Press the “ignition” button on the front panel and observe the spark.
e)
Connect a suitable gas source to the equipment, and verify that there is no
leakage.
f)
Press and hold the over-ride button on the “gas shutoff” valve.
g)
Whilst pressing the “Ignition” button, lightly open the gas control valve on the
front panel and set a gas flow to approximately 0.25-0.5 litres/minute. During this process
the burner will ignite. Keep the over-ride button on the “gas shutoff” valve pressed for
approximately 30 seconds, after which time, the Flame Failure thermocouple will have
heated up sufficiently to activate the “gas shutoff” valve. Vary the gass flow on the gas
control valve and observe the flame. Ensure that the flame is controllable and does not
extinguish at higher gas flows.
Note: If the flame does extinguish, shut the gas supply off immediately and investigate the
promble. The gas pressure may have to be reduced.
h)
Once the operator is satisfied that the “burner” is functioning, push the burner
assembly back into the Steam Boiler.
3. Starting Procedure
a) Ensure that the correct burner jets are used for the gas supply and that the pressure of
the supply has been regulated to limit the maximum flow (2200cc/min for propane- see
above). The tap on the fuel flow meter is used to controle the gas flow once the burner
is ignited. The burner is protected by a thermal cut out. To ignite the burner the burner
over-ride button must be pressed to allow gas to flow before igniting the gas with the
spark igniter. The correct sequence is:
a. Pull back the burner assembly by the circular knob on the front of the bouiler.
b. Press and hold the Gas Cut Out Over-ride.
c. Open the fuel flow meter valve by a few degrees and observe the flowat rising.
d. Press the Igniter button until the gas ignites.
e. Wait a few moments until the thermal cut out is hot, release the Gas Cut Out
Over-ride button.
f. Check that the gas is still ignited by viewing through the grill on the boiler guard.
Safety Note: It is essential that throughout the operation of the boiler the operator is aware
of the burner and boiler water level. If the flame goes out the gas supply should be switched
off immediately. The flame should not be re-ignited until all gas has dispersed. The burner will
become very hot in operation and serious burns will result if the operator touches the burner,
boiler, turbine or steam lines.
g. Push the burner assembly back into the boiler and adjust to a low flame to allow
the Boiler to warm up slowly and evenly.
h. The flame should be stable and not lifting away from the burner or causing high
exhaust temperatures and excessive soot deposits – check quantity and pressure
of gas if these optimum burning conditions cannot be obtained.
b) The water will rise in the gauge glass to a level higher than the original one due to the
expansion of the water as it becomes heated.
Note: It is inadvisable to allow the water to rise above the top water gauge connection.
c) Turn on the water to the condenser and adjust the flow to around 0.5 lt/min.
d) Increase the gas flow to the burner up to approximately 1.25 lt/min.
e) Allow steam pressure to rise to approximately 50 psi as read on the boiler pressure gauge.
f) Slowly open Boiler steam outlet valve fully and turn back quarter of a turn to prevent the
valve from sticking. Operating the boiler steam outlet valve slowly enables all the pipe
work etc. to eat up evenly, and also prevents the Boiler pressure dropping too much
during this period.
g) Observe as the turbine speed increases until a steady state is established. The bulb over
switch 1 will illuminate and the voltage and current generated by the dynamometer can
be observed on the respective meters on the front panel.
4. Running Procedure
a) When carrying out a test, fill the Boiler with water to a height of approximately ¾ viewed
in the water gauge glass. Conduct the experiment in the time taken for the water level to
fall to the bottom of the water gauge glass. By using this method the Boiler steam
pressure can be maintained as no ‘cold’ water is admitted to the Boiler. Do not let the
water level fall below the level of the sight glass as there is a risk of damage or explosion
if the boiler runs dry.
b) The steam turbine is loaded by switching load onto the dc generator by means of the
lamps.
c) The turbine speed is measured using the hand held optical tachometer supplied.
Operating instructions are provided with this instrument.
d) Set the gas flow rate to maintain a steady boiler pressure. Do not let the pressure increase
above 4.5 bar. The safety valve will release very hot steam above this pressure.
5. Experimental Procedure
a) Carefully read all of the instructions in the pre-start, start, running, shutdown and safety
sections of this lab sheet. If you do not understand any of the instructions, or any of the
warnings obtain clarification before you commence.
Always observe the burner flame and the boiler water level. Immediately switch off the gas supply
if the burner goes out. Remember the burner is very hot. Add water by using the feed pump if the
water level falls below one quarter of the sight glass.
b) Start the cooling water flow through the condenser as instructed in the starting
procedure.
c) Light the gas burner as instructed in the starting procedure.
d) Allow the steam pressure in the boiler to rise to 4 bars and then start the engine as
described in the starting procedure.
e) Switch on bulb one to load the engine, adjust the fuel flow to hold a constant boiler
pressure whilst the generator is producing at a voltage of approximately 9 volts.
f) When the system is stable star the test period by collecting the condensate and taking
the readings as indicated in the Table of Results.
g) Condensate may measured by weighing the deposit over a fixed period of time (3 times)
or alternatively by measuring the time required to fill a fixed volume (100 ml).
h) Change the loading on the turbine by increasing the number of switches selected and
repeat the test/data collection as required.
6. Shutdown Procedure
a)
Reduce the load from the dynamometer to only one switch selected.
b)
Turn off the gass supply at the bottle. This will use up the gas in the supply line
and the burner will extinguish.
c)
Close the gas valve on the apparatus.
d)
Allow the Turbine to run until the steam pressure in the boiler has fallen to a safe
level.
e)
Close the boiler steam valve.
f)
Allow the condenser cooling water to flow until all the heat has been carried away
and then turn off the boiler from overfilling as the boiler cools.
g)
For “long term” shutdown the boiler should be drained, and the services isolated
or disconnected.
7. Objectives
The main objectives of the experiment are to determine the following factors:
i.
Boiler efficiency
ii.
Equivalent evaporation of boiler
iii. Distribution of energy and energy balance in the boiler iv. Tests
on
determine efficiencies
v.
Energy transfer in the turbine/ generator system
vi.
Energy transfer in condenser system
vii. Total energy transfer and Plant efficiency.
turbine
to
Some other more objectives (MSc Engg/Researchers only)
i. Compare the output at different turbine speed for the same pressure. ii. The boiler efficiency
(in terms of steam production) at different gas flows (enven if the turbine is not generating
electrical output – BB the drive belt can be removed at low powers). iii. The condenser will not
generate a vacuum, however performance can be checked with varying flow rates of condenser
cooling water/ condensate temperature.
Data Sheet
Name of the student:
Student Id:
Date:
Loading conditions
Unit
Dynamometer Voltage
volts
Dynamometer Current
amps
Boiler Pressure
barg
Boiler Fuel Flow
lt/min
Cooling water Flow
cc/min
Recorded Speed
rpm
Steam Turbine speed
rpm
Dynamometer Speed
rpm
T1 Ambient air
°C
T2 Boiler Feedwater
°C
T3 Boiler Steam
°C
T4 Turbine Inlet
°C
T5 Turbine Exhaust
°C
T6 Cooling water In
°C
T7 Cooling water Out
°C
T8 Condensate
°C
Condensate collected in 2 min
ml
Condensate Flowrate
Switch 1
Switch 3
Switch 4
ml/min
lt/hr
Ambient Temperature
20°C
Atmospheric Pressure
1028 mbar
Signature of the course teacher:
Switch 2
Date:
Data Sheet for Sample Calculation
Name of the student:
Student Id:
Date:
Loading conditions
Unit
Switch 1
Switch 2
Switch 3
Switch 4
Dynamometer Voltage
volts
9
5.6
4
2
Dynamometer Current
amps
0.095
0.145
0.19
0.2
Boiler Pressure
barg
4.7
4.6
4.6
4.6
Boiler Fuel Flow
lt/min
0.75
0.75
0.75
0.75
Cooling water Flow
cc/min
0.9
0.9
0.9
0.9
Recorded Speed
rpm
1200
846
622
432
Steam Turbine speed
rpm
5000
3525
2592
1800
Dynamometer Speed
rpm
4547
3205
2357
1637
T1 Ambient air
°C
20.5
21
22
22
T2 Boiler Feedwater
°C
39
33
31
30
T3 Boiler Steam
°C
176
176
178
180
T4 Turbine Inlet
°C
150
151
152
152
T5 Turbine Exhaust
°C
66
80
76
73
T6 Cooling water In
°C
21
18
17
17
T7 Cooling water Out
°C
31
30
30
29
T8 Condensate
°C
62
63
60
60
Condensate collected in 2 min
ml
44
48
49
48
ml/min
22
24
24.5
24
lt/hr
1.32
1.44
1.47
1.44
Condensate Flowrate
Ambient Temperature
20°C
Atmospheric Pressure
1028 mbar
Signature of the course teacher:
Date:
Sample Calculation Sheet
Note: Due to possible component changes, the results obtained on the equipment supplied may
vary from those given in the following table. The method of calculation remains the same.
Wt. of condensate collected in 2 mins
=
48 gms
Barometric pressure =
14.51 lbs/sq.in. = 1 bar
Fuel used – propane C3H8 at 20 ins water gauge.
Assumptions to be made
Propane
Flue gas
Air
:
Calorific value
93.15 MJ/m3
:
Specific heat
Density
Density
1.5 kJ/kg-K
1.969 kg/m3
1.339 kg/m3
Specific heat
Temperature
1.05 kJ/kg-K
205°C
Velocity
Density
0.4 m/s
1.293 kg/m3
Specific heat
0.993 kJ/kg-K
:
Turbine Details.
Steam pressure at Turbine Inlet P = 0.5 barg
Back pressure
Pb = 0 barg
Calculation for data analysis:
Fuel.
Propane CV 93.15 MJ/m3
Propane flow
Total energy input =
Steam.
Mass flow of steam
Specific enthalpy of steam at (4.6+1) bar and 176°C
T
=
176+273 = 449 K
𝐶𝑃449
49
=
𝐶𝑃400 + 50 (𝐶𝑃450 − 𝐶𝑃400 )
=
1.901+0.98(1.926-1.901) = 1.925 kJ/kg-K
𝑡𝑠5.7
=
𝑡𝑠5.5 + 50 (𝑡𝑠6.0 − 𝐶𝑠5.5 )
ℎ176
5.7
=
=
=
155.5 + 0.4(158.8 – 155.5) = 156.5°C
ℎ5.7 + 𝑐𝑝 (𝑡 − 𝑡𝑠 )
2754.6 + 1.925(176 - 156.5) = 2792 kJ/kg
ℎ5.7
=
ℎ5.5 + 50 (ℎ6.0 − ℎ5.5 )
hfw
=
=
2753 + 0.4(2757-2753) = 2754.6 kJ/kg
4.18×33 = 137.9 kJ/kg
20
Where
20
Calculation for Efficiencies:
1.
Boiler
2.
Equivalent Evaporation of
Efficiency
the boiler
hfg = 2257 at 100°C and 1 bar
3.
Energy balance in the Boiler
Energy supplied from combustion of fuel 69.9 kJ/min = ECV
Energy to production of steam Est =
Energy to flue gases.
Note: Boiler flue gas velocity 0.4 m/s
Boiler flue gas pipe 30 mm diameter
Flue gas sp vol 0.747 m3/kg i.e. 1.339 kg/m3 density
Flue gas sp heat 1.05 kJ/kg – K
Exhaust gas temp. Tg = 205° C
From the data above, energy to flue gas
Where
Energy supplied = 69.9 kJ/min
Energy used
Energy to steam
63.7 kJ/min 91.1%
Energy to exhaust
4.4 kJ/min
6.3%
Energy to surroundings 1.8 kJ/min
2.6%
Total
69.9 kJ/min 100%
4.
Test of Turbine to Determine Efficiencies
Generator efficiency taken to be 70%
Turbine power
=
a) Mechanical
b) Brake
Efficiency =
thermal
where Energy supplied per sec
5.
Energy transfer in turbine/ generator system
Efficiency
6.
Figure 7: Energy transfer system.
Total Energy Transfer and Plant Efficiency
Figure 8: Total Energy transfer
7.
Energy Transfer in Condenser System Input:
Input to condenser = exhaust from turbine
Steam at T5 = 80° C, 1 bar absolute flowing at 24 gm/min
Hence energy in steam input to condenser
where
Initial energy in cooling water (0.9 lt/min at 18°C)
Output:
Energy to condensate (24 gm/min at
Final energy in cooling water (0.9 lt/min at
Energy to radiation = (1055 + 1128.6) – (105.3 + 1881) = 197.3W
EXPERIMENT NO – 4
Name of experiment: Study of Gas Turbine (Jet) Engine
OBJECTIVE :
a.
b.
Identification and studying functions of different engine components.
Study of air intake system, combustion system and air exhaust system.
GAS TURBINE ENGINE :
Sir Frank Whittle ( 1907-1996, England ) is the father of Jet engine which is also known as gas
turbine engine.
PROCEDURE :
1.
2.
3.
Study the gas turbine engine.
Record the purpose and dimension of major structural part.
Draw the schematic diagram of gas turbine engine.
Student Name:
Student ID:
DATA :
Major structural part
Purpose
Inlet duct
Compressor
Combustion chamber
First stage nozzle guide vane
First stage rotor of turbine
Second stage nozzle guide vane
Second stage rotor of turbine
After burner duct
Outlet flame stabilizer
Inner flame stabilizer
Diffuser
ASSIGNMENT :
1.
2.
3.
What are the difference between piston engine and gas turbine engine.
Write down the name of different type of aircraft engine (gas turbine).
A gas turbine engine provides power continuously, is it true? Explain why?
DISCUSSION :
Discuss the above study and do some comment about the experiment.
EXPERIMENT NO – 05
Name of the Experiment: Determination of Carbon Residue of a Given Fuel
1.
Objectives: To find the percentage of carbon residue from various types of liquid, semiliquid or solid fuel.
2.
Specimen: Different types of liquid, semi-liquid or solid fuel.
3.
Procedure
a.
Switch on the power supply.
b.
Supply nitrogen gas (N2) and adjust the pressure by using the pressure controller knob and
pressure gauge.
c.
Take the weight of clean sample vials and record the mass to the nearest 0.1 mg. During
weighing and filing, hold the vials with forceps to keep the weighing errors minimum.
Take sample into the empty vials, re-weigh and record. Calculate the weight of the sample.
Place the loaded sample vials into the vial holder.
d.
Processing of samples:
i).
Place the vial holder into the oven chamber and secure the lid. Care should be taken
not to touch the thermocouple with sample basket feet. The flow rate should not be
raised to 600 ml/min. Then adjust N2 needle valve.
ii)
Confirm that the nitrogen gas (N2) pressure gauge indicates 150 kPa and the gas
flow meter shows 150 ml/min, then press the START switch.
iii)
The flow rate of nitrogen automatically increases to 600 ml/min for the first 10
minutes after pressing the START switch. If the flow rate does not rise to 600
ml/min then adjust the N2 needle valve.
iv)
The temperature and flow rate of nitrogen will be controlled automatically as per
Fig-1. The temperature and flow program will be completed in 98 minutes
approximately.
v)
Afterwards, the buzzer intermittently sounds for about 10 seconds and “P End”
appears on the display board of the program controller.
vi)
Press the RESET switch to disappear the “P End” and ready for repeating the test.
vii)
When oven temperature becomes lower than 250 ºC, place the lid to the lid rest to
cool down and remove the vial holder by using hook for further cooling in
desiccators.
viii)
Start the next test or turn the MAIN switch OFF after the oven temperature falls
below 100 ºC.
e)
Final weighing: keep the sample vials to desiccators till it reaches to room temperature.
Weight the cooled vials to the nearest weighing scale and record the reading. Handle the
vials with forceps.
f)
Temperature and Flow Program diagram:
Figure 1: Temperature and flow Program Diagram
Student Name:
Student ID:
4. Result
Table-1: (Experimental data and calculated result)
No
of
obs.
Sample
Name
Temp
(ºC)
Time
(sec)
1.
2.
3.
4.
5. Calculation
Weight of vial + 10 gm sample = W1 gm
Weight of vial + Carbon Residue = W2 gm
Loss of fuel = (W1 – W2) gm
Carbon Residue, A=10 - (W1 – W2) gm
% of Carbon residue=
A
 100 .
10
Weight of
Sample
(gm)
Weight of
Carbon
Residue
(gm)
% of Carbon
Residue
Remarks
EXPERIMENT NO – 06
Name of the experiment: Proximate Analysis of Coal
1. Objective
An analysis of coal that may be made with the minimum equipment is the proximate analysis
(sometimes called an engineering analysis). The four constituents which are determined in this
type of analysis are:
i)
Moisture
ii)
Ash
iii)
Volatile matter
iv)
Fixed carbon
2. Apparatus
i)
Chemical balance sensitivity at least to 1/10 mg
ii)
Porcelain capsules (Royal, Mission no. 2) about 7/8 in, in depth and 1.75 in. in diameter,
with flat aluminum covers.
iii)
Electric oven with temperature regulation to 110˚C (230˚F) and heaving a renewal of air,
at the rate of 2 to 4 times a minute, that has been dried by passing through sulfuric acid.
iv)
Electric muffle furnace with temperature regulation between 700˚C and 750˚C and with
good air circulation.
v)
Platinum crucible with tightly fitting cover 10 to 20 cu cm.
vi)
Electric tube furnace with temperature regulation to 950˚C + 20˚C.
vii)
Coal samples passed through a no. 60 sieves and no. 20 sieves
Moisture determination
Preface
Some of the moisture in the coal is known as inherent moisture. It is inherently a part of the
structure of the coal and cannot be readily separated from it. The rest of the moisture is called free
moisture which will be heated and the length of time it is held at the elevated temperature is
dependent on the temperature. It should be evident that there is no way of determining the true
free moisture in coal.
Test procedure
i)
Transfer with a spoon or spatula about 1 gm of the 60-mesh sample to one of the porcelain
capsules previously heated and dried in desiccators.
ii)
Cover the capsule and weigh.
iii)
Then dry for 1 hour keeping uncovered in the preheated oven at about 107˚C+ 3˚C.
iv)
Cool in a dissector over sulfuric acid and then weigh.
v)
The 20-mesh sample should be similarly treated, using a 5 gm portion and drying for 1.5Hr.
Ash Determination
Preface
During the heating process, there may be oxidation of some of the material constituents of the
coal. The products of the oxidation may or may not be driven off from the coal. In addition, there
may be some decomposition of mineral constituents, with some of the products being vaporized.
Although the procedure outlined below for ash determination will not give the absolute value of
the ash in the coal, qualitative results may be obtained when conditions of the determinations are
duplicated.
Test procedure
i)
The porcelain capsules containing the dried coal from the moisture determination should
be uncurbed and placed in the furnace when the furnace is cold.
ii)
Gradually heat the sample.
iii)
Stop the ignition between 700˚C and 750˚C, with occasional stirring with a platinum or
nichrome wire, until all carbon particles disappear.
iv)
Cool the sample in desiccators and then weigh.
v)
Then continue alternate heating and weighing until weight is constant.
Volatile Meter Determination
Preface
In addition to moisture, coal contains volatile constituents, primarily hydrocarbons, which will be
drive off by heating. It should be recognized that the amount of volatile matter found by this
process is a function of the heating time and the temperature. To obtain qualitative results, both
of these variables must be controlled.
Mechanical losses occur when some coals are heated rapidly due to the rapid release of volatile
matter or steam. The mechanical losses are recognized by the “sparking” that occurs when the
small fragments of the coal are heated to incandescence as they are being expelled. Therefore,
care should be taken to avoid sparking. If any sparking occurs, the test results are worthless and
the test procedure should be modified. A new coal sample should be slowly lowered into the
furnace and gradually heated for a period of 5 to 10 min. The crucible may now be lowered into
the regular position and heated at the standard temperature for a period of 7 min precisely.
Test procedure
i)
Weigh a 1gm sample of 60 mesh coal in a platinum crucible, cover and place in a furnace
chamber which has been preheated to 950˚C+20˚C (1742˚F+36˚F).
ii)
Heat exactly 7 minutes
iii)
Remove the coal without disturbing cover.
iv)
Now weigh
v)
Volatile matter = Loss of weigh – minus moisture
Fixed carbon determination
Preface
The reminder of the carbon cannot be drive off by the heating is called fixed carbon.
There is no direct way of determining the fixed carbon in a coal, and hence it must be calculated
by subtracting the summation of the moisture, ash and volatile matter weights from the original
weight of the coal.
Although fixed carbon cannot be vaporized, some of it will burn quite rapidly in the presence of
oxygen, particularly at the temperatures used in the volatile matter determination. Hence, care
must be exercised to prevent oxygen from entering the close fitting cover on the crucible.
EXPERIMENT NO: 07
Name of the Experiment: Study and Calibration of Pressure Gauge by
Dead Weight Tester
INTRODUCTION
The dead weight tester is a primary measuring instrument, being designed to be used for
calibratingthe secondary measuring instruments and generating standard pressure for various
tests.
BOURDON TUBE PRESSURE GAUGE:
When a curved tube of approximately elliptical cross section is subjected to an internal
pressure, it has a tendency to straighten. If one end of the tube is fastened there will be definite
movement of the other which depends on the magnitude of the applied pressure. If the pressure
within the tube is reduced bellow that surrounding of the tube. The tube will have a tendency
to curve still further in a smaller arc. The tube itself resists and if not stretched beyond its
elastic limit, will return to its original position when the pressure is removed. Such a tube is
the so called bourdon tube pressure gauge. By means of a suitable linkage, the motion of the
free end of the tube is transmitted to a rack and pinion which rotates a needle mounted on the
face of the gauge.
Bourdon tube pressure gauge are often classified
1.
2.
3.
Pressure gauge ( for pressure above atmospheric)
Vacuum gauge ( for pressure below atmospheric)
Combination gauge ( for both vacuum and small positive gauge pressure)
Pressure gauges are normally graduated in pounds per square inch. Although for special
applications they may have other graduations, such as feet of water. Vacuum gauges normally
are graduated in inches of mercury. The vacuum part of combination gauges generally is
graduated in inches of mercury and pressure part in psi.
DEAD WEIGHT TESTER:
The most satisfactory method of calibration of pressure gauges is to use a dead weight gauge
tester.In the dead weight tester, a pressure is impressed on oil, which transmits this pressure
equally to known area and to the gauge under test. Thus the piston and the weight give
knowledge of the true oil pressure which is acting on the gauge.
OPERATION PROCEDURE:
1)
2)
Open the ram cylinder stop valve, release valve, and gauge valve in which a gauge is
mounted. Then, fully turns counterclockwise the fine adjust pump, and close the
release valve.
Put weight (each weight is stamped with the nominal pressure) corresponding to the
specifiedpressure. Be sure to add the weight of the ram plate itself.
For a combination system dead weight type pressure gauge of non-Pa unit, put a conversion
weight on the ram plate of Pa unit, and then weight of non-Pa unit.
When using the gauge in non-Pa unit, do not add the pressure of the ram plate because the
pressure of the ram plate and conversion weight indicated on the conversion weight as 1A
& 1B.
To generate pressure of two different units using a set of ram cylinder, the masses of
theweights of each unit must be changed.
To change the ram plate, the mass of which is determined on the basis of the Pa unit,
intoother than the Pa unit, you must correct its mass with a conversion weight.
For example, the ram plate itself generates a pressure of 0.05 MPa. A conversion weight
putthe ram generates pressure of 1 kg f/cm2.
3)
Pressurize the Gauge with the pre-loading pump and find adjustment pump line referring
to the indications on the monitor gauge until the ram plate rises about 12 mm above the
cylindertop *1 Turning the weights clockwise slightly will generate the specified pressure.
In this state, read the indication on the gauge.
4)
To raise pressure in steps, put weights corresponding to the specified pressure
sequentiallyand repeat the procedure in → (3).
5)
Decrease the weight in similar manner and again note the corresponding pressure gauge
reading.
6)
Find the error and percentage error.
7)
Plot percentage error against observed gauge reading and observe pressure against actual
pressure on different graph paper.
8)
Discuss the curves and the experiment as a whole.
DATA SHEET:
Area of Piston: …………………..Wt. Piston &weight platform: …………………
No of Obs.
Actual
pressure
Pressure gauge reading
Up
Down
%Error
Mean
EXPERIMENT NO – 08
Name of the Experiment: Determination of Calorific value of Gaseous Fuel by Gas
Calorimeter
Objectives
To find out the calorific value of natural gas using gas calorimeter.
Apparatus
Gas calorimeter, Wet-gas meter, Gas controller, Gas burner, Thermometers, Water container, Lighter
Identification of Components
Figure 1: Sectioned view of a typical Boys calorimeter.
SUMMARY OF OPERATION PRODUCER
i)
Connect a tube from the cooling water source to the inlet to calorimeter; the inlet is the
connection at the perimeter of the top plate of the unit.
Connect a tube from the Calorimeter water outlet (at the center of the top plate) to the
drain source.
ii)
Connect a tube from the gas supply to the wet test meter (Hyde meter) gas supply inlet
located at the top of near side.
iii)
Connect a tube from Hyde meter outlet of the gas control value inlet. Connect a gas control
valve outlet with the burner inlet located at the bottom plate of Calorimeter.
iv)
Set the water flow rate: 1500-200 ml/min
v)
Check the water level at the definite level in the sight box of Hyde meter.
vi)
Pull out the inner casing first and then outer casing from the calorimeter main body. Set
the gas flow rate 1.5-2.5 liter/min by regulating the quadrant valve and ignite flame by
gas lighter.
vii)
After ignition check all gas connecting points by soap-bubble to ensure zero leakage.
viii)
Put the outer casing on the calorimeter base plate and then place the inner casing around
the flame very slowly.
ix)
Observe the water outlet temperature. Outlet temperature must rise up. If not, flame may
be extinguished and need to ignite again.
x)
After ignition the flame set the minimum required position in quadrant valve.
xi)
Allow the gas to burn and the water to flow through the calorimeter for a least 30 minutes
to allow the operating condition in steady state.
xii)
During experiment observe gas flow and cooling water flow to ensure the flow is perfectly
OK.
xiii)
After stabilization, collect the required data (viz., inlet gas flow temp., inlet water temp.,
outlet water temp., volume of collected water, volume of collected condensate, volume of
gas, and time) for calculation.
xiv)
Repeat … . For 2nd and 3rd observations gas flow should be increased.
xv)
After collecting necessary data, stop the gas flow first by the main gas flow valve and then
after 10-12 minutes stop the cooling water flow.
xvi)
After 20-25 no. of analysis or when calorimeter will be in idle position for a long time,
Calorimeter inner casing and outer casing should be cleaned with the Alkali (soda)
solution then with fresh water and dried with Tissue paper.
WARNING
i)
Never stop cooling water flow while fuel gas is burning.
ii)
When gas flow or cooling water flow discontinue at any time on analysis condition, stop
the gas flow main valve.
iii)
When water outlet temperature goes down, it means the flame is out. Try again to ignite
the flame as early as possible.
iv)
When water outlet temperature is abnormally high (above 60ºC), stop the gas flow main
valve. Otherwise, calorimeter will be seriously damaged.
v)
Never connect Hyde meter with supply gas pressure above 48 mbar (20 ins of water).
FORMULA AND TABLE
Qgross =
mw
 tCw  GVf
VG
Where,
Qgross=Gross calorific value, kJ/m3
Mw=Quantity of water in Kg
VG= Gas volume in m3
∆𝑡 =Temperature difference in o C
Cw = Specific heat of water (4.187 kJ/kg ºC)
GVf = Gas volume factor
Student Name:
Student ID:
Table: observed data for determining calorific value.
Water
Ser
No
Gas Inlet
Temp(ºC)
Inlet
Temp
(ºC)
Outlet
Temp
(ºC)
Water
collected
Kg
Condensate
collected
Kg
Calculation
Gross (Higher) heating value (HHV)
Calorimeter value in MJ/m3 & BTU/ft3
Water inlet temperature
:
Water outlet temperature
:
Temperature difference ( t )
:
Gas inlet temperature
:
Water collected (mw)
:
Number of revolution
:
Gas volume (VG)
:
Barometric pressure
: 760 mmHg
Corresponding GVf
:
Specific heat of water (Cw)
: 4.187 kJ/kg ºC
Q gross =
mw
 tCw  GVf
VG
In BTU/ft3 =Qgross ×26.8413=......................... BTU/ft3
Gas
Barometric
flow
Corresponding
pressure
(1 rev)
GVf
mmHg
3
m
Time
sec
Net (Lower) heating value(LHV)
𝑄𝑛𝑒𝑡 = 𝑄𝑔𝑟𝑜𝑠𝑠 − 𝑄𝐻𝐸
𝑄𝐻𝐸 = 𝑟 × 𝐶𝑊
Where
Qnet = Net (Lower) heating value
QHE = Heat of Evaporation
r = Heat of condensation of water = 2.454 kJ/gm at 20ºC =2.454 MJ/kg
Cw = condensate in kg/m3
During ………….sec gas volume =2.36×10-3 m3
And during ……….. sec condensate = ……….gm = ………....kg
Cw = (condensate kg)/(2.36×10-3)= ……………kg/ m3
Qgross = Qnet + QHE
Qnet = Qgross - QHE
Qnet =
In BTU/ft3 = Qnet ×26.8413 =.................BTU/ft3