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 pressure Fuel injection timing Type of combustion chamber Fuel and cycle : Kirloskar, TV1 Make : Four stroke, compression ignition, Constant speed vertical, Water cooled, Direct injection, Variable compression ratio : One : 87.5 mm X 110 mm : 661 cc : 38.35 cc : 5. kw : 17.5: 1 (Standard engine) & 15:1 18:1(VCR) : 1500 rpm : 10 bar : 3 0 CA btdc : Hemispherical open combustion chamber : Diesel & Diesel Lubricating oil : SAE 40 Connecting rod length Valve diameter Maximum valve lift Fuel injection pump : 38 mm : 34. mm : 10.1 mm : MICO inline, with mechanical governor and Flange mounted.
169 APPENDIX SPECIFICATIONS OF THE DYNAMOMETER Make : SAJ Test Plant pvt. Ltd., Type : Eddy current Model : AG-0 Power : Max. 0 kw @ 450 rpm Speed : 10000 rpm Effective radius of arm : 0.195 m
170 APPENDIX 3 SPECIFICATIONS OF THE COMBUSTION ANALYSER Make : AVL Combustion Analyser Type : 619 Indimeter Hardware Indwin Software version. TECHNICAL DATA General For indoor use Soiling level Mains connection : 85 65 V, 50 60 Hz, 60 VA 1 fuse 3.15 A slow-blow, Fuse holder on rear panel The internal power supply unit fuse may only be replaced by a service engineer. Temperature range: + 5 C to + C, once the system reaches its operating temperature after a initial warm-up period, it can be used at temperatures down to 10 C. Maximum relative humidity 80 % for temperatures up to 31 C, following a linear decrease to 50 % relative humidity at 40 C, non-condensing Dimensions: Approx. 44 mm 58mm 370 mm depth incl. cable, Connectors : 500 mm Weight: approx. 8 kg
171 Analog Part 4 (Standard), 6 or 8 differential voltage inputs 10 V, input resistance 100 Input low-pass filter fg 100 khz Simultaneous sample & hold input ADC 1 bit Digital Part Digital signal processor RAM 8 MB Measurement resolution: 0.1, 0., 0.5, 1 degree CA Input CDM, Trigger: TTL signal (necessary input for LOW approx. 7 ma) Entire data transfer rate: Max. 1 MHz PC interface: parallel port, Link interface (option)
17 Charge Amplifier Data Input type Input insulation impedance : 10 14 : Unbalanced, high insulation (approx. 10 14 connection of piezoelectric measurement transducers ) for Connector : BNC sockets at front and rear (parallel connection) Overload protection : Input protected against excessive electrostatic voltages or charges occurring during operation or handling. Output type : Unbalanced, output ground electrically isolated from protective ground and input ground via a differential amplifier Ground loop problems are appreciable reduced due to the use of two electrically isolated 15 V sources. Connection : 13 a to 13 c on the 64-pin connector Voltage : 0 10 V at load 0.5 k Current : Max 18 ma Output impedance : < 0.01 Quiescent potential : Zero or + 1 V, selectable by slide switch (RESET state) adjustable by 0.7 V with potentiometer ZERO Temperature drift : RESET, TRANSSENS. (10.00PC/bar): 1 mv/ C
173 APPENDIX 4 SPECIFICATIONS OF THE SMOKE METER Make : AVL 437 Smoke meter Type : IP 5 Accuracy and reproducibility : 1 % full scale reading Measuring range : 0 to 100 opacity in % 0 to 99.99 absorption m -1 Measurement chamber : Effective length 0.430 m 0.005m Heating time : 0 V approximately 0 min. Light source : Halogen bulb 1 V / 5W Maximum smoke temperature : 50 C Power supply : 190 40 V AC, 50 Hz,.5 A Dimensions : 570mm 500mm 150mm
174 APPENDIX 5 SPECIFICATIONS OF AVL DI-GAS ANALYSER Make : AVL Type : AVL Di-Gas 444 Power supply : 11. voltage 5 W Warm up time : 7 min. Connector gas in : 180 I/h, max. overpressure 450 hpa Response time : T 95 15s Operating temperature : 5-45 C Storage temperature : 0 to 50 C Relative humidity : 95%, non-condensing Inclination : 0-90 Dimension (w x d x h) : 70 mm x 30 mm x 85 mm Weight : 4.5 kg net weight without accessories Interfaces : RS 3 C, Pick up, Oil temperature probe.
175 APPENDIX 6 ERROR ANALYSIS AND UNCERTAINITY ANANLYSIS The physical quantities of the equipment are subject to uncertainties. Hence the uncertainly analysis is needed to prove the accuracy of the experiments. In order to have reasonable limits of uncertainly for a computed value an expression is derived which is 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..., x,... 1 xn (A6.1) and let error limits for the measured variables or parameters be x 1, n1, n,......, x a x a (A6.) 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 1 R R R R x1 x... xn (A6.3) x x x n 1/
176 Using equation (A6.3) the uncertainty in the compound values such as brake thermal efficiency and fuel flow measurements were estimated. The measured values such as speed, fuel time, voltage and current are estimated from their respective uncertainties based on the Gaussian distribution. For fuel time ( t r ) and fuel volume ( t), the uncertainties are takes as 0. sec and 0.1 sec respectively. A sample calculation is given below. Example: Speed N 1500rpm Fuel volume fx 10cc Brake power BP 5.Kw 1. Total fuel consumption (TFC) TFC 10 3600 0.83 t 1000 TFC 10 3600 0.83 4.15 1000 1.37 kg / h TFC f(t) tfc T tfc T 10 10 t 4.15 3600 0.83 1000 3600 0.83 1000-0.051 kg/h TFC TFC t t 1 (A6.4) 0.04949 0. 0.010 kg/h.
177 The uncertainty in the TFC from equation (A6.4) 0.010 kg/h and the limits of uncertainty are (1.37) (0.010) kg/h.. Brake thermal efficiency ( ) BP 3600 100 TFC CV f (BP,TFC) 5. 3600 100 1.8 4700 34.5% BP 3600 100 TFC 4700 3600 100 1.8 4700 6.85 TFC BP 3600 100 TFC 4700 5. 3600 100 1.8 4700 6.75% BP p TFC C (A6.5) 6.85* 0.199.64* 0.0104 1.4 % The uncertainty in the brake thermal efficiency from equation (A6.5) is 1. 4 % and the limits of uncertainty are 34.5 1.4%.
178 3. Temperature Measurements Uncertainty in temperature is 1% (T 150 C) % (150 C T 50 C) 3% (T 50 C) 4. Percentage of uncertainty for the measurements of speed, mass flow rate, NO x, Hydrocarbon, Smoke and pressure are given below: (i) Speed : 1. (ii) Mass flow rate of air : 1.3 (iii) Mass flow rate of diesel : 1.3 (iv) NO X :.4 (v) Hydrocarbon :.3 (vi) Smoke :.1 (vii) Pressure : 1.0