Main conditions and effectiveness of gas fuel use for powering of dual fuel IC self-ignition engine

Abstract

11# Summary. Internal combustion engines are fuelled mostly with liquid fuels (gasoline, diesel). Nowadays the gaseous fuels are applied as driving fuel of combustion engines. In case of spark ignition engines the liquid fuel (petrol) can be totally replaced by the gas fuels. This possibility in case of compression engines is essentially restricted through the higher self-ignition temperatures of the combustible gases in comparison to classical diesel oil. Solution if this problem can be achieved by using of the dual fuel system, where for ignition of the prepared fuel gas -air mixture a specified amount of the liquid fuel (diesel oil) should be additionally injected into the combustion chamber. For assurance that the combustion process proceeds without mistakes and completely, some basic conditions should be satisfied. In the frame of this work, three main aspects of this problem are taken into account: a. filling efficiency of the engine, b. stoichiometry of the combustion, c. performance of mechanical parameters (torque, power). A complex analysis of these conditions has been done and some achieved important results are presented in the paper.

Combined use of coal mine gases for efficient energy generation

“…The real combustion process takes place at a certain excess of the air (so also the oxygen O 2 ), which is expressed by the air excess ratio λ ≥ 1 [6,7]. Therefore, the actual specific amount of air supplied is…”

“…The gas air-methane mixture with a slightly higher content of methane CH 4 , it means at z M > z M,max can also be ignited (it is also usually a serious mine explosion hazard); however, a combustible mixture by more than stoichiometric participation of methane should not be directly used [7,8] for fueling of different energy plants (e.g., boilers, gas turbines, internal combustion engines).…”

“…Serious difficulties in this area (e.g. using them as the fuel for internal combustion (IC) engine) occur mainly in relation to the ventilation gas, whereas the gas from demethanation of coal deposits can be used directly as the fuel for IC engines [6][7][8].…”

“…A different situation is characterized by utilization of the gas from demethanation of coal deposits; the main combustible component methane occurs in relative stoichiometric excess, which means that for the full and complete combustion of this gas an additional amount of oxidant (air, oxygen O 2 ) should be supplied into the combustion chamber [2,9]. In view of the above it was noted, that it is possible to prepare the good gas combustible mixture (mainly in the aspect of the appropriate oxygen excess ratio, λ [7,8]) -by adequate mixing of the ventilation gas stream with the gas stream from demethanation of coal deposits.…”

The Use of Denoising and Analysis of the Acoustic Signal Entropy in Diagnosing Engine Valve Clearance

“…Vibroacoustic signals were also used in [19,20], where excessive clearance between the piston and the cylinder sleeve of the engine was detected. Another interesting study was described in [21][22][23][24][25][26], where vibroacoustic signals were used for analyzing the influence of the type of fuel supplied to the engine on its work characteristics. Another issue analysed during this research was the impact of various types of mixtures, such as gasoline, LPG (Liquefied Petroleum Gas) and mixtures with the addition of hydrogen, on the generated vibroacoustic signals.…”