Investigation of Alcohol Sprays


We aimed to test the spraying features being very important for the utilisation of alcohol fuels. So we built a test plant in order to examine the spray pattern and the injection dose.

The build of the test equipment: the fuel pump placed under the liquid level pumped the fuel into the pressure governor. The fuel pressure and temperature was measured before the pressure governor. The fuel entered the spray nozzle from the branch under governed pressure. The supply-voltage was measured at the driving unit of the spray nozzle. The injection time (t3) could be controlled by 0,1 us definition. The weight was measured by a 1 mg-definition scale. The injected dose was tested as a function of the fuel pressure, temperature, density and viscosity.  For the measurement we applied a tank where evaporation could be excluded during the test. During the measurement significant change in the controlled pressure was not found, however the temperature increased by 4-6°C, probably due to the fuel pump operation in the liquid.

 
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For the analysis of the spray pattern a LASER curtain was applied with timed flashes.  The LASER could be switched on an off in us definition after starting time of the injection. The width of enlightened strip is 1mm in the centre of the spray nozzle. The injection process can be decomposed into steps as many as required by modification of timing (t1) of the lightening and the injection' cone angle can be measured.
 

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Ethanole Spray

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Reference Benzin Spray

The density and the viscidity is a variable, but interfacial tension too can affect the angle of spray cone and pattern. Now we research how we can measure exactly this property of injection. It seems the alcohols are not well atomize fuels, because the spray pattern more narrow, and collapse like the gasoline at this injector. The next time we change the measure system, and made variable pressure regulator to change the fuel pressure.

Brüller Péter - Dr. Meggyes Attila - Dr. Bereczky Ákos: Examination of Spraying Characteristics in case of Methanol Fuel, XXXVI. Combined Conference on Heavy Vehicles (BusTruck 2005), Budapest, Hungary, Paper No. E-07., 2005