APPENDIX 1 TECHNICAL DATA OF TEST ENGINE

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1 156 APPENDIX 1 TECHNICAL DATA OF TEST ENGINE Type Four-stroke Direct Injection Diesel Engine Engine make Kirloskar No. of cylinder One Type of cooling Air cooling Bore 87.5 mm Stroke 110 mm Displacement volume 661 cc Piston (Standard) Hemispherical Compression ratio 17.5:1 Rated power 4.4 kw ( rpm Injection timing 3 o btdc Nozzle opening pressure 00 bar Fuel oil Commercial High Speed Diesel Type of governor Mechanical Centrifugal type Lubrication system Forced Feed Valve Timing Inlet valve opening 5 o CA btdc Inlet valve closing 35 o CA abdc Exhaust valve opening 35 o CA bbdc Exhaust valve closing 5 o CA atdc

2 157 APPENDIX EXHAUST GAS ANALYSER AND SMOKE METER EXHAUST GAS ANALYSER Automotive exhaust gas analyzer Measuring item Measuring Method Model QRO 40 Make: QROTECH CO LTD., Korea Measuring range Resolution CO (%) NDIR HC (ppm) NDIR CO (%) NDIR NOx (ppm) Electrochemical SMOKE METER Type and make : TI diesel tune, 114 smoke density testers TI Tran service Piston displacement : 330 cc Stabilisation time : minutes Range : 0 10 Bosch smoke number Minimum time period : 30 seconds Calibrated reading :

3 158 APPENDIX 3 PRESSURE TRANSDUCER AND CHARGE AMPLIFIER PRESSURE TRANSDUCER Model : KISTLER, Switzerland. 601 A, water cooled. Range : 0 50 bar Sensitivity : pc/ bar Linearity : 0.1 < ± % FSO Acceleration sensitivity : <0.001 bar/g Capacitance : 5 pf Weight : 1.7 g Connector, Teflon insulator : M CHARGE AMPLIFIER Make : KISTLER Instruments, AG Switzerland Measuring ranges : stages graded pc± ::5 and steeples 1 to 10 Transducer sensitivity : 5 decades, pc/m.u Of two most sensitive range (%) : <± 3 Of other range stages (%) : <±1 Linearity of transducer Sensitivity (%) : <±0.5 Calibration input, sensitivity pc/mv : 1±0.5

4 159 APPENDIX 4 ERROR ANALYSIS AND UNCERTAINTY All measurements of physical quantities are subject to uncertainties. Uncertainty analysis is needed to prove the accuracy of the experiments. In order to have reasonable limits of uncertainty for a computed value an expression is derived as follows: Let `R be the computed result function of the independent measured variables x 1, x, x 3,... x n, as per the relation. R = f (x 1, x,... x n ) (A4.1) and let error limits for the measured variables or parameters be x 1, ± n 1, x ± n,..., x a ± x a and the error limits for the computed result be R ± R Hence to get the realistic error limits for the computed result the principle of root mean square method is used to get the magnitude of error given by Holman (1973) as R R R R x1 x... x n x1 x x n 1/ (A4.) Using Equation (A4.) the uncertainty in the computed values such as brake power, brake thermal efficiency and fuel flow measurements were estimated. The measured values such as speed, fuel time, voltage and current

5 160 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 Voltage and ± 0.16 Ampere respectively. For fuel time t and fuel volume (t), the uncertainties are taken as ± 0. sec and ± 0.1 sec respectively. A sample calculation is given below: Example: Speed N ~ 1500 rpm Voltage V = 30 volts Current I = 16 Ampere Brake power B.P = 4.4 kw VI 1. BP kw x 1000 g BP = f (V,I) BP I V (0.85x1000) (0.85x1000) BP V I (0.85x1000) (0.85x1000) BP BP BP V xi V I (A4.3) = kw

6 161 Therefore, the uncertainty in the brake power from Equation (A4.3) is ± kw and the uncertainty limits in the calculation of BP are 4.4 ± kw.. Total fuel consumption (TFC) TFC 10 x 3600 x 0.83 (t x 1000) TFC TFC = f (t) 10 x 3600x 0.83 (3x1000) 1.33 kg/h tfc (10 x 3600 x 0.83) T t x 1000 TFC t (10 x 3600x 0.83) (3) x kg/h TFC TFC t x tt (A4.4) (0.0564x0.) = kg/h The uncertainty in the TFC from equation (A4.4) kg/h and the limits of uncertainty are (1.33) ± (0.011) kg/h. 3. Brake thermal efficiency () BP x 3600 x100 TFC x CV

7 16 = f (BP, TFC) 4.4 x3600 x x 4500 (3600 x 100) BP TFC x x100 (1.33 x 4500) 8.08 % TFC TFC (BP x 3600 x100) (TFC) x 4500 (BP x 3600 x100) (TFC) x 4500 (4.4 x3600 x100) (1.33) x 4500 = xp xc (A4.5) BP TFC ( 6.368*0.0711) ( 1.069x0.011) = 0.51 % The uncertainty in the brake thermal efficiency from Equation (A4.5) is ± 0.51 % and the limits of uncertainty are ± 0.51%. 4. Temperature Measurement Uncertainty in the temperature is: ± 1% (T > 150 C) ± % (150 C < T < 50 C) ± 3% (T < 50 C)

8 163 APPENDIX 5 HEAT RELEASE RATE ANALYSIS The heat release rate is a quantitative description of the burning pattern in the engine. An understanding of the effects of heat release rate on cycle efficiency can help to study the engine combustion behavior. The pressure-crank angle variation is the net result of many effects like combustion, change in cylinder volume and heat transfer from the gases in the engine cylinder. In order to get the effect of only the combustion process, it is necessary to relate each of the above processes to the cylinder pressure and thereby separate the effect of the combustion process alone. The method by which this is done is known as the heat release analysis. The heat release data provides a good insight into the combustion process that takes place in the engine. Based on the first Law of thermodynamics the apparent heat release rate is expressed as follows: dq hr = du + dw + dq ht (A5.1) where, dq hr - Instantaneous heat release modeled as heat transfer to the working fluid du dw - Change in internal energy of the working fluid - Work done by the working fluid dq ht - Heat transmitted away from the working fluid (to the combustion chamber walls)

9 164 Change in internal energy can be written as, du = Cv / R (PdV + VdP) (A5.) Work done by the working fluid dw = PdV (A5.3) Heat transfer rate to the wall can be written as, dq ht / dt = ha (T g T w ) (A5.4) where R - Gas Constant T, P, V are Temperature, Pressure and Volume respectively Cv - Specific heat at constant volume h - Heat transfer coefficient A T w - Instantaneous heat transfer surface area - Temperature of the wall. T g - Temperature of the exhaust gas From Equation (A5.1), the first law of thermodynamics can be written as follows with suitable assumptions during the period when the valves are closed. dqhr dv 1 dp dt P V has(tg Tw) dq 1 d 1 d d (A5.5) where is crank angle in degrees, is the ratio of specific heats of the fuel and air. A s is the area in m through which heat transfer from gas to combustion chamber walls take place. Pressure value is obtained from the cylinder pressure data at corresponding crank angle.

10 165 If the engine is air cooled then the equation is: dv 1 dp dqht P V 1 d 1 d (A5.6) This relation makes it possible to calculate the heat release rate. All the quantities on the right hand side are known or can be easily derived once the pressure time history is recorded.

11 166 APPENDIX 6 EMISSION VALUES CONVERSION All measured emission values are converted to g/kwh in order to quantify the emissions with respect to brake power. The following are the formulas used and sample calculation for the conversion of respective emission parameters: Values for TMI technique at full load for the acetylene flow rate of 90 g/h. Mass of diesel m diesel = 0.88 kg/h Mass of acetylene m gas = 0.9 kg/h Mass of fuel m fuel = 1.17 kg/h Mass of air m air = 4.94 kg/h NO x emission = 1460 ppm UHC emission = 3 ppm CO emission = % CO emission = 7.40 % Brake power BP = 4.4 kw 1. NO x emission NO x (g / kwh) (m air mfuel ) NOx (ppm) BP (A6.1) NO x (g / kwh) (ppm) g / kwh

12 167. Unburned hydrocarbon emission UHC (g / kwh) (m air mfuel ) UHC (ppm) BP (A6.) UHC (g / kwh) (ppm) g / kwh 3. Carbon monoxide emission CO (g / kwh) CO (g / kwh) (mair mfuel ) 10 CO (%) 8 (A6.3) 9 BP (%) g / kwh 4. Carbon dioxide emission (mair mfuel ) 10 CO (%) 44 CO (g / kwh) (A6.4) 9 BP CO (g / kwh) (%) g / kwh

13 168 APPENDIX 7 OPERATIONAL COST ANALYSIS FOR ACETYLENE DIESEL DUAL FUEL OPERATION The use of alternate fuels in internal combustion engines depends on the technical feasibility and economic viability. Although many alternative fuels are technically feasible they are not used in internal combustion engines due to their higher cost. From the consumer s point of view, fuel cost is a predominant factor than the other factors such as availability, production methods, transportation and energy equivalent to petroleum products. The fuel economics of acetylene diesel dual fuel mode are calculated and compared with diesel fuel as given below. Fuel cost analysis for neat diesel fuel operation at full load Cost of the Diesel fuel for 1 litre (i.e. 830 kg/m 3 ) USD = Rs Cost of 1 kg of diesel (USD) fuel = Rs Diesel fuel consumed per hour = 1.33 kg Brake Specific Fuel Consumption = 1.33/4.4 = 0.30 kg/kwh Cost for one unit of power Produced = = Rs 14.50

14 169 Fuel cost analysis for acetylene diesel dual fuel operation cost diesel Diesel consumed per hour in dual fuel mode = 0.88 kg/h Acetylene consumed hour in dual fuel = kg/h operation 1 kg cost of acetylene = Rs Total fuel cost in dual fuel mode for = cost of diesel + cost of one unit acetylene = 0.88 x x 89 = Rs Dual fuel cost per kwh = /4.4 = Rs 17.54/ kwh Cost of dual fuel mode is higher by = 17.54/14.50 = 1.0 times The cost of acetylene diesel dual fuel operation is higher by 1.0 % times than that of diesel fuel for producing one unit of power output per one hour.

APPEFNDIX 1 SPECIFICATIONS OF THE TEST ENGINE

168 APPEFNDIX 1 SPECIFICATIONS OF THE TEST ENGINE Make and Model General details Number of cylinders Bore X Stroke Swept volume Clearance volume Rated output Compression ratio Rated speed Nozzle opening