APPENDIX 1 SPECIFICATION OF THE TEST...
Transcript of APPENDIX 1 SPECIFICATION OF THE TEST...
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APPENDIX 1
SPECIFICATION OF THE TEST ENGINE
Make and model : Kirloskar, AV-1 make
General Details : Four stroke, Compression ignition, Constant
Speed, vertical, water cooled, direct
injection.
Number of cylinders : one
Bore : 80 mm
Stroke : 110 mm
Swept volume : 553 cc
Clearance volume : 36.87 cc
Compression ratio : 16.5 : 1
Rated output : 3.67 kW at 1500 rpm
Rated speed : 1500 rpm
Injection pressure : 200 bar
Fuel injection timing : 23 deg CA BTDC
Type of combustion chamber : Hemispherical open combustion chamber
Fuel : High Speed diesel
Lubricating oil : SAE 40
Connecting rod length : 235 mm
Valve diameter : 33.7 mm
Maximum valve lift : 10.2 mm
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APPENDIX 2
ELECTRICAL DYNAMOMETER
Make and Model : Laurence Scott and electromotor Ltd.,
Norwich and Manchester, UK
Volts : 220/230
Maximum power : 10 kW
Windings : Shunt
Rated current : 43.5 A
RPM : 1500
Rating type : Continuous
Machine No. : 103320
APPENDIX 3
EXHAUST GAS ANALYSERAutomotive exhaust gas analyzer Model QRO 402
Make: QROTECH CO LTD., Korea
Measuring item Measuring method Measuring range Resolution
CO (%) NDIR 0.00 - 9.99 0.01
HC(ppm) NDIR 0 - 15000 1
CO2(%) NDIR 0.0 - 20.0 0.01
NOx(ppm) Electrochemical 0 - 5000 1
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APPENDIX 4
SMOKE METER
Type and make : TI diesel tune, 114 smoke density tester TI
Transervice
Piston displacement : 330 cc
Stabilisation time : 2 minutes
Range : 0 – 10 Bosch smoke number
Minimum time period : 30 sec
Calibrated reading : 5.0 ± 0.2
APPENDIX 5
PRESSURE TRANSDUCER
Model : KISTLER, Switzerland.
601 A, water cooled.
Range : 0 to 250 bar
Sensitivity : -14.80 pC/ bar
Linearity : 0.1 < ± % FSO
Acceleration sensitivity : <0.001 bar/g
Operating temperature range : -196 to 200 0 C
Capacitance : 5 pF
Weight : 1.7 g
Connector, Teflon insulator : M4 x 0.35
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APPENDIX 6
CATHODE RAY OSCILLOSCOPE
Make : Hewlett Packard, HP54600B SERIES
Channels : 2 Nos.
Range : 2 mV/div to 5V/div
Accuracy : ±1.5%
Verniers : finely calibrated
Band width limit : 20 MHZ
Trigger System
dC to 100 MHZ 1 div or 10 m V
Modes : Auto
Hold off : Adjustable from 200 ns to 135
External Trigger
Range : ±18V
Sensitivity : dc to 100 MHZ 100mV
Input resistance : 1 M
Input capacitance : 13 pf
Display System
7 inch raster CRT
Resolution 255 vertical by 500 horizontal points
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Acquisition System
Maximum sample rate : 20 MSa/s
Resolution : 8 bits
Advanced Functions
Voltage : Varg, Vrms, Vp-p, Vtop, Vbase, Vmin, Vmax
Time : Frequency, period, +width, -width, duty cycle, rise
time and fall time
Cursor : manual or automatic
Autoscale : Vertical / Horizontal
Power : Line Voltage 100 Vac to 240 Vac
Line Voltage selection-Automatic
Line Voltage frequency-45 HZ to 440 HZ
Maximum power : 220VAConsumption
General
Humidity : 95% Rh +40°C
Temperature : -10°C to 55°C
MIL-T-28800D for type III, class 3, style D
EMI
MIL-T- FTZ 1046 Class B
Vibration : 15 min along each of 3 xy axis
Displacement, 10 HZ to 55 HZ in one man cycle
Weight : 6.2 Kg.
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APPENDIX 7
CHARGE AMPLIFIER
Make : KISTLER Instruments
AG, Switzerland
Measuring ranges : 12 stages graded
pC ±10…500’000
1:2:5 and stepless 1 to 10
Transducer sensitivity, 5 decades : (*) pC/M.U. 0,1…11’000
Continuously adjustable between
Accuracy
Of two most sensitive ranges % <± 3
Of other range stages % <±1
Linearity of Transducer Sensitivity % <±0,5
Potentiometer adjustment
Calibration capacitor pF 1’000±0,5
Calibration input, sensitivity pC/mV 1±0,5
Input Voltage, maximum with pulses V ±125
Widths < 0, 3 s
Linearity (**) %FSO <±0,05
Frequency response error with standard
Filter 180 kHz at 50 kHz % -1…+3
at 100 kHz % <±5
3-dB-frequency with standard filter kHz 180±10%
180 kHz, input capacitance up to 200 pF
Time constant resistor setting Long, about 1014
setting Medium, about 1011
setting Short 109
Time constant, = Rg Cg setting Long s >1’000…>100’000
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setting Medium s 1 …5’000
setting Short s 0’01…50
Voltage output, unlimited short circuit proof
Full scale output (**) V ±10
Output current mA ±5
Output impendance 100±5%
Open circuit saturation voltage V >±12..< ±15
Cable noise signal, due to input capacitance pCrms/pF <3 10-5
Hum and noise, input shielded (***) mVrms <0,3/<2
Zero offset during reset, over 10 hrs. (***) mV <±1 / <±5
Zero error, during reset, due to supply
Voltage variations±20% (***) mV <±1 / <±10
Thermal zero shift, during reset
Due to temperature changes (***) mV/°C <±0,5 / <±5
Drift, due to leakage current of input pC/s <±0,03
MOSFET, at 20°C
Adjustment range for zero offset, input stage mV ±200
Output stage mV ±250
(*) M.U. = mechanical unit, e.g. Bar, N, g.
(**) FSO = full scale output
(***) Dial for transducer sensitivity adjustment set to 10-00 resp. 1-00
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APPENDIX 8
ELECTRONIC BALANCE
Make : SHIMADZU, Japan
Model : AY62
Weighing capacity : 62 g
Minimum display : 0.1 mg
Standard deviation ( ) : mg
Linearity : ± 0.2 mg
External weight value for : 60 g
Calibration
Pan diameter : Ø 80 mm
Stability of sensitivity : ± 2 ppm / °C
(10°C to 30°C)
Operating temperature : ± 5 to 40°C
Range
Power supply : Input 100 – 250 VAC
APPENDIX 9
TACHOMETERMake : FUJI, Japan
Type : MECHANICAL
Range : 0 – 10,000 rpm
Resolution : 20 rpm
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APPENDIX 10
HOT AIR OVEN
Name : SRICO electric hot air oven with digital temperature
Controller
Power supply : 220 V, 50 Hz.
Temperature range : 50 – 250 C
Accuracy : 1 C
Mode of control : Auto-digital controller
Mode of heating : Imported BDG 80 / 20 nickel wire
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APPENDIX 11
ERROR AND UNCERTAINTY ANALYSIS
Error is associated with various primary experimental measurements and
the calculations of performance parameters. Errors and uncertainties in the
experiments can arise from instrument selection, condition, calibration,
environment, observation, reading and test planning. Uncertainty analysis is
needed to prove the accuracy of the experiments. The percentage uncertainties
of various parameters like load and brake thermal efficiency were calculated
using the percentage uncertainties of various instruments given in Table 3.2.
An uncertainly analysis was performed using the equation
Total percentage uncertainty
= Square root of{(uncertainty of TFC)2 +(uncertainty of load)2 +
(uncertainty of brake thermal efficiency)2 + (uncertainty of CO)2 + (uncertainty
of unburned HC)2 + (uncertainty of NOx)2 + (uncertainty of smoke number)2 +
(uncertainty of exhaust gas temperature)2 + (uncertainty of pressure pickup)2}
= square root of {(1) 2 + (0.2) 2 + (1) 2+ (0.2) 2+ (0.2) 2 + (0.2) 2+ (1) 2+
(0.15) 2+ (1)2}
= ± 2.28 %
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The errors associated with various measurements and in calculations of
performance parameters are computed in this section. The maximum possible
errors in various measured parameters namely temperature, pressure, exhaust
gas emissions, time and speed estimated from the minimum values of output
and accuracy of the instrument are calculated using this method. This method is
based on careful specification of the uncertainties in the various experimental
measurements.
If an estimated quantity, R depends on independent variable like(x1, x2, x3…….
xn) then the error in the value of “R” is given by
R = f (x1, x2, ................... xn) (A 11.1)
with `R’ as the computed result function of the independent measured variables
x1, x2, x3, ..................... xn, as per the relation.
x1, ± x1, x2 ± x2, ......................., xa ± xa
as the error limits for the measured variables or parameters
and the error limits for the computed result as R ± R
To get the realistic error limits for the computed result, the principle of
root-mean square method was used to get the magnitude of error given by
Holman 1973
2/122
22
2
11
.................. nn
xxRx
xRx
xRR
(A11.2)
Using equation A11.2 the uncertainty in the computed values such as
load, brake thermal efficiency and fuel flow measurements were estimated. The
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measured values such as speed, fuel time, voltage and current were estimated
from their respective uncertainties based on the Gaussian distribution. The
uncertainties in the measured parameters, voltage ( V) and current ( I),
estimated by the Gaussian method, are ± 3 V and ± 0.14 A respectively. For
fuel time ( tr) and fuel volume ( t), the uncertainties are taken as ± 0.2 sec and
± 0.1 sec respectively.
A sample calculation is given below
Example:
Speed N = 1500 rpm
Voltage V = 230 volts
Current I = 14 A
Fuel volume fx = 10 cc
Brake power BP = 3.74 kW
1. Brake power
kW1000 x
VIBPg
BP = f(V,I)
0.016279)(0.86x1000
14)(0.86x1000
IVBP
0.267441)(0.86x1000
230)(0.86x1000
VI
BP
2BP
2BP
BP IVIV (A11.3)
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22 14.0267441.03016279.0 xx
= 0037868.0
= 0.061536 kW
Therefore, the uncertainty in the brake power from equation A11.3 is
± 0.061536 kW and the uncertainty limits in the calculation of B.P are 3.74 ±
0.061536 kW.
2. Total fuel consumption (TFC)
1000)(t x0.85 x3600 x10TFC
hkg /1.044371000) x(29.3
0.85 x3600 x10TFC
TFC = f(t)
1000 xt0.85) x3600 x(10
Ttfc
2
035643.01000 x(29.3)
0.85) x3600 x(10Ttfc
2 kg/h
2
ttxt
TFCTFC (A11.4)
2)2.0035643.0( x
= 0.0071286 kg/h
The uncertainty in the TFC from equation A11.4 is 0.0071286 kg/h and
the limits of uncertainty are (1.04437) ± (0.0071286) kg/h.
3. Brake thermal efficiency ( )
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CV xTFC100 x3600 xBP
= f (BP, TFC)
%98135.2943000 x1.04437
100 x3600 x3.74
43000xTFC100) x(3600
BP
016405.843000) x(1.04437100 x3600
43000 x(TFC)100) x3600 x(BP
TFC 2
43000 x(1.04437)100) x3600 x(3.74
2
= 28.70 %
2
TFCxTFC
BPxBP
(A11.5)
22 )0071286.070.28()061536.0016405.8( xx
= 0.53403 %
The uncertainty in the brake thermal efficiency from equation A11.5 is
± 0.53403 % and the limits of uncertainty are 29.98135 ± 0.53403 %
4. Exhaust Gas Temperature Measurement
Al/Cr K-type thermocouple is used to measure the exhaust gas
temperature. Digital temperature indicator displays the temperature measured
by thermocouple. The maximum possible error in the case of temperature
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measurement is calculated from the minimum values of the temperature
measured and accuracy of the instrument (thermocouple with temperature
indicator) the errors in the temperature measurement are:
T/T)EGT = (( Tk-Type/ Tk-Type)2 + ( Tindi/ Tindi )2)1/2
T/T)EGT = ((0.48/160)2 + ( 0.468/ 160 )2)1/2
T/T)EGT = 0.0041 =0.41%
5. Combustion chamber pressure measurement
The combustion chamber pressure was measured by using pressure
transducer and charge amplifier.
P/P)Exp = (( q charge / qcharge)2 + ( VPT/ VPT )2)1/2
P/P)Exp = ((0.16/ 100)2 + (0.15/ 100)2)1/2 = 0.002193= 0.22%
6. Percentage of uncertainty for the measurement of speed, mass flow rate
of air, mass flow rate of diesel, NOx, hydrocarbon and smoke is given below:
i) Speed : 1.1
ii) Mass flow rate of air : 1.3
iii) Mass flow rate of diesel : 1.0
iv) NOX : 1.1
v) Hydrocarbon : 0.01
vi) CO : 0.8
vii) CO2 : 1.2
vi) Smoke : 2.0
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APPENDIX 12
HEAT RELEASE ANALYSIS
The details about combustion stages and events can be determined
by analyzing the heat release rates determined from cylinder pressure
measurements. Analysis of heat release can help to study the combustion
behaviour of the engine. The analysis for the heat release rate is based on the
application of first law of thermodynamics for an open system. It is assumed
that the cylinder contents are homogeneous mixture of air and combustion
products and are at uniform temperature and pressure during the combustion
process. The first law for such a system is written as
dQhr = dU + dW + dQht (A12.1)
where,
dQhr = Instantaneous heat release modeled as heat transfer to the working
fluid
dU = Change in internal energy of the working fluid
dW = Work done by the working fluid
dQht = Heat transmitted away from the working fluid (to the combustion
chamber walls)
Change in internal energy is written as,
dU = Cv/R (pdV+Vdp) (A12.2)
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Work done by the working fluid dW = pdV
Heat transfer rate to the wall is written as dQht/dt = h A (Tg-Tw) (A12.3)
where R = Gas constant
T,P,V are Temperature, Pressure and Volume respectively.
Cv = Specific heat at constant volume
h = Heat transfer co efficient
Tw = Temperature of the wall: 400 K
8.055.08.02.026.3 wTpBh
Where
B (bore) = 0.080 m
P(cylinder pressure) = 29.327 bar
T (gas temperature) = 2100 K
w is average gas velocity in m/s which is calculated from the equation
)(21 mcc
cdp pp
VpTV
CSCw (A12.4)
Where
SP is the mean piston speed in m/s, Vd is the displaced volume in m3
Tc, pc, Vc are temperature, pressure and volume respectively during combustion
p is the cylinder pressure during combustion
pm is the pressure in motorized condition
C1 is 2.28 and C2 is 3.24x10-3 during combustion
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From the equation, the first law of thermodynamics can be written as
follows with suitable assumptions:
ddt)TwTg(hA
ddp
11V
ddVP
1dQ sht (A12.5)
Where is the crank angle in degrees
is the ratio of specific heats of the fuel and air
As is the area in m2 through which heat transfer from gas to combustion
chamber walls takes place.
The pressure value is obtained from the cylinder pressure data at
corresponding crank angle. Equation (A12.1) makes it possible to calculate the
heat release rate. The calculated heat release rate is as follows with the given
values
Clearance volume = 3.68x10-5 m3 , Swept volume = 0.00055392 m3
=1.3, Crank radius = 0.055m
Stroke = 0.11 m, Compression ratio = 16.5
At 350O CA the pressure is 31.327 bar and at 351O CA the pressure is 31.614
bar. The heat release rate is
ddt)TwTg(hA
ddp
11V
ddVP
1dQ sht
018.61
2078013.1
1000297128.01
00000480.0293270013.1
3.1htdQ
)018.658106.2000016.61(htdQ
6.87htdQ Joules/ºCA