1. POWERING OF A SPARK IGNITION GENERATOR (4 STROKE) USING A LOCALLY MADE PROPANE VENTURI MIXER BY Erameh Andrew, Adingwupu Anthony, Nwabuisi Alphonsus and Olisah Erick

2. INTRODUCTION

3. Cont’d

4. Cont’d

5. Cont’d

6. METHODOLOGY-MATERIALS USED
Mild steel cylindrical pipe.
Butterfly valve.
Hose.
Clips.
Propane gas.
Gasket
Gasoline generator firman1900dx.
Number of cylinders 1
Number of strokes 4
Volumetric displacement cc or 5litres
Starting system Recoil
Frequency Hz
Voltage rated V
Rated output KW
Maximum output KW
Manifold diameter mm
Phase Single
Volumetric Efficiency 70%
Engine speed rpm
Engine specifications and parameters Values

7. METHODOLOGY-DESIGN OF THE VENTURI MIXER.
Air flow rate requirement of engine Q is given by
𝑸= 𝝅 𝑫 𝟐 𝑳 𝜼 𝒗 𝑵 𝟒×𝟔𝟎
D = Bore of engine= 0.05m
L = Stroke of engine= 0.49m
𝜼 𝒗 =Volumetric efficiency of engine=70%,
N = Speed of rotation of Engine =1500rpm

8. DESIGN OF THE VENTURI MIXER Cont’d
Inlet Air velocity
The velocity of air at inlet is given by
𝑽 𝟏 = 𝑸 𝑨 𝒊𝒏
Velocity of air at throat
𝑽 𝟐 = 𝑸 𝑪 𝒅 𝑨 𝟐
Air Pressure at throat
Assuming steady, one dimensional, incompressible, isentropic flow; the Bernoulli’s theorem at section 1 and 2
𝑷 𝟐 = 𝑷 𝟏 + 𝝆 𝒂 𝟐 𝑽 𝟏 𝟐 − 𝑽 𝟐 𝟐

9. DESIGN OF THE VENTURI MIXER Cont’d
Velocity of gas at throat
The gas velocity at throat at which it enters the engine is given by (Arali and Kulkarni, 2013)
𝑽 𝟐𝒈 = 𝑲 𝒗 × 𝟐 𝝆 𝒈 × 𝑷 𝟏𝒈 − 𝑷 𝟐𝒈
Mass of air at throat
The mass of air at throat is given by equation (3.7) as seen in Baylar (2007)
𝒎 𝒂 = 𝝆 𝒂 × 𝑽 𝟐 × 𝑨 𝟐
Mass of gas at throat
The mass of fuel at throat is determined using
𝒎 𝒈 = 𝒎 𝒂 𝑨𝑭𝑹
AFR = stoichiometric air fuel ratio for a propane gas in a spark ignition engine =15.67:1 (Danardono1, 2011)

10. DESIGN OF THE VENTURI MIXER Cont’d
Diameter of gas supply pipe
The area of gas entrance at throat is given by
𝒅 𝒈 = 𝟒× 𝒎 𝒈 𝝆 𝒈 ×𝒏×𝝅× 𝑽 𝟐𝒈
MATLAB code was developed with the above equations varying the diameter of air inlet pipe from 0 to 0.08m to determine corresponding diameter of gas supply pipe that will give AFR of 15.67, also corresponding pressure drop and velocity of the mixed gas were determined from the code.

11. RESULTS- DETERMINATION OF DIAMETER OF INLET AIR PIPE

12. RESULTS- DETERMINATION OF THE DIAMETER OF INLET GAS PIPE

13. SUMMARY OF CALCULATED PARAMETERS
Specifications
Size
Diameter of air inlet pipe
25.4mm (1 Inch)
Length of air inlet pipe
200mm
Diameter of gas inlet pipe
10mm
Length of biogas inlet pipe
20mm
Diameter of outlet throat pipe(manifold)
19mm
Number of holes for gas entrance 1
Thickness of mild steel sheet and pipe
2mm

15. Bill of Engineering Materials and Evaluation (BEME)
Quantity
Cost (#)
Mild steel sheet metal 300mm by 300mm 1
1,000
Mild steel cylindrical pipe (1 inch)
1 inch butterfly valve
150
Labour
2,000
Finishing
500
Miscellaneous Expenses
Total
5,650

16. Performance analysis of the Venturi Mixer - PROPANE AND PETROL ENGINE VOLTAGE OUTPUT CAPACITY

17. Performance Analysis of the Venturi Mixer-Exhaust Emission

18. Performance analysis of the Venturi Mixer-FUEL CONSUMPTION RATE TEST

19. CONCLUSION
A MATLAB code was developed base on the models derived from Bernoulli’s principle of flow in pipes to simulate the best inlet pipe diameters of air and gas that will give the highest pressure drop and velocity at the throat of the mixer not neglecting the stoichiometric air fuel ratio of the fuel used.
Performance test was carried out using the fabricated venture mixer to determine the Load bearing capacity base on voltage output using voltmeter readings, exhaust emission and fuel consumption rate tests using petrol and propane as fuel.
From the results analysis, it can be concluded that using propane as fuel with the help of the fabricated venturi mixer using locally available materials gave better results compared to petrol.

20. THANK YOU ALL