Research of combustion in older generation spark-ignition engines in the condition of use leaded and unleaded petrol

This paper analyzes the potential problems in the exploitation of the older generation of spark-ignition engines with higher octane number of petrol (unleaded petrol BMB 95) than required (leaded petrol MB 86). Within the experimental tests on two different engines (STEYR-PUCH model 712 and GAZ 41) by applying piezoelectric pressure sensors integrated with the engine spark plugs, acceleration sensors and special electronic block connected with distributor, show that the cumulative first and second theoretical phase of combustion when petrol of higher octane number (BMB 95) is used lasts slightly longer than when the low-octane petrol MB 86 is used. For new petrol (BMB 95) higher optimal angles of pre-ignition have been determined by which better performances of the engine are achieved without a danger of the combustion with detonation (also called knocking)

Research of combustion in older generation spark-ignition engines in the condition of use leaded and unleaded petrol

This paper analyzes the potential problems in the exploitation of the older generation of spark-ignition engines with higher octane number of petrol (unleaded petrol BMB 95) than required (leaded petrol MB 86). Within the experimental tests on two different engines (STEYR-PUCH model 712 and GAZ 41) by applying piezoelectric pressure sensors integrated with the engine spark plugs, acceleration sensors and special electronic block connected with distributor, show that the cumulative first and second theoretical phase of combustion when petrol of higher octane number (BMB 95) is used lasts slightly longer than when the low-octane petrol MB 86 is used. For new petrol (BMB 95) higher optimal angles of pre-ignition have been determined by which better performances of the engine are achieved without a danger of the combustion with detonation (also called knocking)

Research of combustion in older generation spark-ignition engines in the condition of use leaded and unleaded petrol

This paper analyzes the potential problems in the exploitation of the older generation of spark-ignition engines with higher octane number of petrol (unleaded petrol BMB 95) than required (leaded petrol MB 86). Within the experimental tests on two different engines (STEYR-PUCH model 712 and GAZ 41) by applying piezoelectric pressure sensors integrated with the engine spark plugs, acceleration sensors (accelerometers) and special electronic block connected with distributor, show that the cumulative first and second theoretical phase of combustion when petrol of higher octane number (BMB 95) is used lasts slightly longer than when the low-octane petrol MB 86 is used. For new petrol (BMB 95) higher optimal angles of pre-ignition have been determined by which better performances of the engine are achieved without a danger of the combustion with detonation (also called knocking)

A quick, simplified approach to the evaluation of combustion rate from an internal combustion engine indicator diagram

In this paper a simplified procedure of an internal combustion engine in-cylinder pressure record analysis has been presented The method is very easy for programming and provides quick evaluation of the gas temperature and the rate of combustion. It is based on the consideration proposed by Hohenberg and Killman, but enhances the approach by involving the rate of heat transferred to the walls that was omitted in the original approach. It enables the evaluation of the complete rate Of heat released by combustion (often designated as gross heat release rate or fuel chemical energy release rate), not only the rate of heat transferred to the gas (which is often designated as net heat release rate). The accuracy of the method has been also analyzed and it is shown that the errors caused by the simplifications in the model are very small, particularly if the crank angle step is also small A several practical applications on recorded pressure diagrams taken from both spark ignition and compression ignition engine are presented as well

The galena flotation in function of grindability

This paper presents the results of industrial research of influence of grinding fineness on the results of galena mineral flotation from the ore of the mine "Rudnik." Based on these results, it has been concluded that with one-stage grinding and one-stage classification of complex Pb-Zn-Cu ore galena is the most easily grinded mineral within the ore

Fleas and flea control

Fleas as hemeatophagous arthropodes take part in the spreading of certain diseases such as bubonic plague, murine typhus, tick-borne typhus tularaemia, or can be transitory hosts for certain species of cestodes for dogs and cats. Depending on the type of host on which fleas persist and the habitat, measures that can be taken to control them can be only sanitary-hygiene, individual, or treatment of the habitat. Sanitary-hygiene measures mostly consist of regular cleaning. Individual protection implies the use of insecticides for re-impregnating clothing, spraying clothing and the use of repellents. Treatment of habitats comprises the use of insecticides of the group of organophosphates, metyl-carbamates, pyrethroids and organo-chlorine compounds, instruments for dusting and spraying. In addition to these compounds, preparations based on imidaclopride, fipronyl and inhibitors of insect growth (IGRs) and development (IDIs) are also used. Flea control in household pets is implemented using measures of individual protection and treatment of their habitats

Dekontaminacija alkidno-karbamidnih boja na metalu kontaminiranih visokotoksičnim jedinjenjima

The paper investigates rates of sorption and desorption of 2,2'-dichlordi-ethylsulphide (sulphur yperite), 1,2,2-trimethylpropyl-methylfluorophosphonate (soman), soman viscous recipe and O-ethyl-S-(2-diisopropyIamino-ethyl) of methyltiophosphonate (VX) on protective alkyd-carbamide paints on metals. Decontamination rates of metal surfaces covered with alkyd-carbamide paint and contaminated by cited contaminants have been..Ispitane su brzine sorpcije i desorpcije 2.2'-dihlordietilsulfida (sunipornog iperita), 1,2,2-trimetilpropil-metil-fluorofosfonata (somana), viskozne recepture somana, 0-etil-S-(2-diizopropilaminoetil) metiltiofosfonata (VX) na zaštitnim bojama alkidno-karbamidnog tipa na metalu. Određene su brzine dekontaminacije metalnih površina obojenih alkidno-karbamidnom bojom i kontaminiranih navedenim kontaminantima. Kao dekontaminanti korišćeni su rastvori: natrijum-hidroksid, kalcijum-hipohlorit u vodi, natrijum-etilat u etanolu i rastvori za dekontaminaciju DS-2 i TD-A. Nađene su optimalne koncentracije aktivnih materija u vodenim rastvorima za dekontaminaciju. Određeni su uticaji temperature dekontaminacionih rastvora na brzinu i efikasnost dekontaminacije

A quick, simplified approach to the evaluation of combustion rate from an internal combustion engine indicator diagram

In this paper a simplified procedure of an internal combustion engine in-cylinder pressure record analysis has been presented. The method is very easy for programming and provides quick evaluation of the gas temperature and the rate of combustion. It is based on the consideration proposed by Hohenberg and Killman, but enhances the approach by involving the rate of heat transferred to the walls that was omitted in the original approach. It enables the evaluation of the complete rate of heat released by combustion (often designated as “gross heat release rate” or “fuel chemical energy release rate”), not only the rate of heat transferred to the gas (which is often designated as “net heat release rate”). The accuracy of the method has been also analyzed and it is shown that the errors caused by the simplifications in the model are very small, particularly if the crank angle step is also small. A several practical applications on recorded pressure diagrams taken from both spark ignition and compression ignition engine are presented as well