Florin MMARIAŞIU, Bogdan VARGA, Teodora Deac, N. CORDOS
To reduce emissions caused by SI engines, gasoline-ethanol blends (bioethanol) represents not only an alternative as well as an immediate response to current and future policies related to reducing pollution. There are numerous scientific studies have shown that bioethanol-gasoline blends has several disadvantages. Functional parameters such as engine power, torque and BSFC are much inferior to the use of gasoline (in particular the use of fuel blends containing a higher volume of bioethanol 20%). One way to reduce these major drawbacks is the conditioning (reforming) of biofuels by external energy intake in the form of direct ultrasonic, which represents an original approach in the biofuels research domain.  The purpose of the experiments is to improve the energetic possibilities of biofuels, to can be use in a great proportion as blended fuel with fossil fuels. The paper presents the experimental results and data’s obtained studying the influence of ultrasonic irradiation process on BE5-BE20 bioethanol-gasoline blends. To determine the influence of external energy on functional parameters of a spark ignition (SI) engine fueled with gasoline and ethanol blends was use an experimental stand equipped, developed and adjusted in accordance with the methodology of research in the field. Parameters considered in carrying out the experimental research are effective power, effective engine torque and brake specific fuel consumption. Experiments show possibilities in improving the energetic potentials of bioethanol-gasoline blends fuels for use in SI engines. Improvements exist for all considered parameters (power, torque and BSFC) for the entire range of engine speeds. For a full understanding of the phenomena that occur during the process of ultrasonic irradiation, future research is needed to determine the chemical transformations that may occur in the frame of this process. Possibilities to appear new class of peroxide compounds during ultrasonic irradiation process (due to the existence of OH radical in the molecular structure of bioethanol) may worsen the long-term storage properties of this class of fuels. Studies are also needed to establish the existence of an optimal-frequency and intensity of radiation to establish the optimum point, linked directly with the economic aspect in the development and application possibilities of such devices on SI engines.
ultrasonic irradiation, bioethanol, SI engine, power, torque, BSFC
Presentation: oral