Zoran Lulic | University of Zagreb (original) (raw)
Papers by Zoran Lulic
Sustainability, 2022
Greenhouse emissions and air pollutants pose a global threat to the environment and human health.... more Greenhouse emissions and air pollutants pose a global threat to the environment and human health. Emission inventories are a valuable tool in understanding emission sources and their overall impact on the environment. Most cities and countries do not include non-road mobile machinery (NRMM) when compiling emission inventories. Furthermore, little effort has been made to understand better the impact of this source of emissions on the environment. For these reasons, this research examines the data from the existing NRMM emission inventories and other studies concerning NRMM emissions. After careful literature review, three main problems in creating a national NRMM emission inventory are identified and reviewed: lack of a comprehensive list of NRMM and their activity data, lack of emission factor data, and lack of research. The data from the existing inventories show that compared to some emissions, NRMM has a three times larger proportion of emissions compared to the proportion of ene...
U radu se opisuju osnovna pravila i povijest natjecanja Formule Student, rađanje tog projekta na ... more U radu se opisuju osnovna pravila i povijest natjecanja Formule Student, rađanje tog projekta na Fakultetu strojarstva i brodogradnje te FSB Racing Team od osnivanja do danas. Također je prikazan prvi, jos nedovrseni hrvatski bolid Formule Student, njegova konstrukcija, odabir komponenti i razrada detalja u svrhu optimiranja performansi. Pokazano je da su studenti uz odgovarajucu podrsku sposobni samostalno izraditi kompletno vozilo te da se može ocekivati i njihov uspjesan nastup i promocija Fakulteta na natjecanju u Velikoj Britaniji.
PROMET - Traffic&Transportation, 2019
Mileage data collected via surveys based on self-estimation, reports from garages and other sourc... more Mileage data collected via surveys based on self-estimation, reports from garages and other sources which use estimations are rough estimates and differ greatly from the actual mileage. Vehicle mileage is a major factor in emission calculations and needs to be as accurate as possible to obtain reliable emission models. Odometer readings are collected annually at the periodic technical inspection in Croatia. Average mileage data were analyzed for vehicles up to 20 years of age in 2017. Vehicles were classified by curb weight and fuel type. Such classification proved to follow driver behavior and the intended purpose of the vehicle. For each vehicle class, the model was applied using the vehicle age and its population size as inputs for calculating average mileage. Real data shows that vehicles in Croatia considerably exceed the estimated mileage in the years following the first registration of the vehicle and that they cannot be compared to data collected in other studies based on es...
Energy Conversion and Management, 2018
Transactions of FAMENA, 2017
U radu je opisano ispitivanje utjecaja primjene biodizela na eksploatacijske parametre i trajnost... more U radu je opisano ispitivanje utjecaja primjene biodizela na eksploatacijske parametre i trajnost motora osobnog vozila. Za potrebe ispitivanja nabavljeno je 1000 litara biodizela te osobno vozilo pokretano Dieselovim motorom. Prije pocetka pogona biodizelom, a s ciljem definiranja pocetnog stanja motora, izmjereni su snaga i moment motora u ovisnosti o brzini vrtnje motora. Nakon toga vozilo je koristeno na uobicajeni nacin pri cemu je za pogon koristen biodizel (B100). Tijekom ispitivanja vođena je detaljna evidencija o utrosenom gorivu, glavnim prijeđenim relacijama te nacinu eksploatacije, a sve s ciljem sto preciznijeg određivanja potrosnje goriva u pojedinim vremenskim periodima i uvjetima. Po zavrsetku ispitnog perioda ponovljeno je ispitivanje snage motora, te su rezultati uspoređeni s onima na pocetku ispitivanja. Također, prije pocetka ispitivanja uzeti su uzorci ulja za podmazivanje motora kao i nakon pogona biodizelom te su njihovom analizom utvrđene promjene svojstava ulja za podmazivanje motora kao posljedica primjene biodizela.
To stay competitive, the companies have to respond quickly to the changing demands of customers. ... more To stay competitive, the companies have to respond quickly to the changing demands of customers. At the same time, the products become more and more complex, including more complex functionalities, and enterprises now have to deal with concurrent multi-disciplinary environments if they want to optimize their products globally. This would come with the development of in-process simulations, but new methods and new tools are needed in order to enable a bridge between the development domains. An important approach is Digital Mock-up (DMU), which provides a robust development method to enable the spatial integration in concurrent environment. In the past decade the DMU has been implemented as a mandatory development method ensuring good project progress within distributed collaborative development. Nevertheless, there is a strong need to pursue the product development by additional methods, which progress beyond DMU. The development of mechatronic systems involves many disciplines, whic...
As a result of the latest trends in the automotive industry that have put stringent requirements ... more As a result of the latest trends in the automotive industry that have put stringent requirements on the fuel consumption and exhaust gas emission, the engine research has been directed towards optimization of the combustion process and application of the variety of cleaner fuels. In that context the use of natural gas as a partial supplement for the liquid Diesel fuel has attracted a lot of attention. This paper presents the literature review of recent research on dual fuel Diesel-natural gas operation. It presents the benefits and drawbacks of dual fuel Diesel-natural gas operation as well as the means and methods to circumvent these drawbacks. The use of natural gas as a partial supplement for Diesel liquid fuel has been suggested due to its cleaner nature of combustion, its worldwide availability and its potential to reduce both global (CO2) and local (NOx, soot) exhaust gas emissions from conventional Diesel engines. As natural gas is consisted primarily of methane (CH4), it has high H/C ratio thus having the theoretical potential to reduce the CO2 emission by nearly 25% compared to conventional Diesel fuel. What makes dual fuel operation possible is the flammability limit between the two fuels and it exploits the advantages of each one. Diesel fuel pilot is used as a high energy ignition device (Diesel fuel pilot releases 10000 times more energy compared to the energy delivered by spark the in spark-ignition engine) while natural gas is used as a primary fuel in the operation. Several dual fuel combustion strategies have been proposed ; (a) conventional dual fuel combustion that operates with premixed natural gas which is ignited by the Diesel fuel pilot ; (b) direct injected dual fuel combustion, where both natural gas and Diesel pilot fuel are directly injected into the cylinder at the end of the compression stroke ; (c) HCCI like combustion (PCCI, RCCI) where combustion is primarily controlled by the natural gas/Diesel fuel ratio. Although dual fuel combustion has shown significant potential it still faces some challenges, among which HC and CO emission at low load and preignition and knock at high load are the major ones.
Sustainability, 2022
Greenhouse emissions and air pollutants pose a global threat to the environment and human health.... more Greenhouse emissions and air pollutants pose a global threat to the environment and human health. Emission inventories are a valuable tool in understanding emission sources and their overall impact on the environment. Most cities and countries do not include non-road mobile machinery (NRMM) when compiling emission inventories. Furthermore, little effort has been made to understand better the impact of this source of emissions on the environment. For these reasons, this research examines the data from the existing NRMM emission inventories and other studies concerning NRMM emissions. After careful literature review, three main problems in creating a national NRMM emission inventory are identified and reviewed: lack of a comprehensive list of NRMM and their activity data, lack of emission factor data, and lack of research. The data from the existing inventories show that compared to some emissions, NRMM has a three times larger proportion of emissions compared to the proportion of ene...
U radu se opisuju osnovna pravila i povijest natjecanja Formule Student, rađanje tog projekta na ... more U radu se opisuju osnovna pravila i povijest natjecanja Formule Student, rađanje tog projekta na Fakultetu strojarstva i brodogradnje te FSB Racing Team od osnivanja do danas. Također je prikazan prvi, jos nedovrseni hrvatski bolid Formule Student, njegova konstrukcija, odabir komponenti i razrada detalja u svrhu optimiranja performansi. Pokazano je da su studenti uz odgovarajucu podrsku sposobni samostalno izraditi kompletno vozilo te da se može ocekivati i njihov uspjesan nastup i promocija Fakulteta na natjecanju u Velikoj Britaniji.
PROMET - Traffic&Transportation, 2019
Mileage data collected via surveys based on self-estimation, reports from garages and other sourc... more Mileage data collected via surveys based on self-estimation, reports from garages and other sources which use estimations are rough estimates and differ greatly from the actual mileage. Vehicle mileage is a major factor in emission calculations and needs to be as accurate as possible to obtain reliable emission models. Odometer readings are collected annually at the periodic technical inspection in Croatia. Average mileage data were analyzed for vehicles up to 20 years of age in 2017. Vehicles were classified by curb weight and fuel type. Such classification proved to follow driver behavior and the intended purpose of the vehicle. For each vehicle class, the model was applied using the vehicle age and its population size as inputs for calculating average mileage. Real data shows that vehicles in Croatia considerably exceed the estimated mileage in the years following the first registration of the vehicle and that they cannot be compared to data collected in other studies based on es...
Energy Conversion and Management, 2018
Transactions of FAMENA, 2017
U radu je opisano ispitivanje utjecaja primjene biodizela na eksploatacijske parametre i trajnost... more U radu je opisano ispitivanje utjecaja primjene biodizela na eksploatacijske parametre i trajnost motora osobnog vozila. Za potrebe ispitivanja nabavljeno je 1000 litara biodizela te osobno vozilo pokretano Dieselovim motorom. Prije pocetka pogona biodizelom, a s ciljem definiranja pocetnog stanja motora, izmjereni su snaga i moment motora u ovisnosti o brzini vrtnje motora. Nakon toga vozilo je koristeno na uobicajeni nacin pri cemu je za pogon koristen biodizel (B100). Tijekom ispitivanja vođena je detaljna evidencija o utrosenom gorivu, glavnim prijeđenim relacijama te nacinu eksploatacije, a sve s ciljem sto preciznijeg određivanja potrosnje goriva u pojedinim vremenskim periodima i uvjetima. Po zavrsetku ispitnog perioda ponovljeno je ispitivanje snage motora, te su rezultati uspoređeni s onima na pocetku ispitivanja. Također, prije pocetka ispitivanja uzeti su uzorci ulja za podmazivanje motora kao i nakon pogona biodizelom te su njihovom analizom utvrđene promjene svojstava ulja za podmazivanje motora kao posljedica primjene biodizela.
To stay competitive, the companies have to respond quickly to the changing demands of customers. ... more To stay competitive, the companies have to respond quickly to the changing demands of customers. At the same time, the products become more and more complex, including more complex functionalities, and enterprises now have to deal with concurrent multi-disciplinary environments if they want to optimize their products globally. This would come with the development of in-process simulations, but new methods and new tools are needed in order to enable a bridge between the development domains. An important approach is Digital Mock-up (DMU), which provides a robust development method to enable the spatial integration in concurrent environment. In the past decade the DMU has been implemented as a mandatory development method ensuring good project progress within distributed collaborative development. Nevertheless, there is a strong need to pursue the product development by additional methods, which progress beyond DMU. The development of mechatronic systems involves many disciplines, whic...
As a result of the latest trends in the automotive industry that have put stringent requirements ... more As a result of the latest trends in the automotive industry that have put stringent requirements on the fuel consumption and exhaust gas emission, the engine research has been directed towards optimization of the combustion process and application of the variety of cleaner fuels. In that context the use of natural gas as a partial supplement for the liquid Diesel fuel has attracted a lot of attention. This paper presents the literature review of recent research on dual fuel Diesel-natural gas operation. It presents the benefits and drawbacks of dual fuel Diesel-natural gas operation as well as the means and methods to circumvent these drawbacks. The use of natural gas as a partial supplement for Diesel liquid fuel has been suggested due to its cleaner nature of combustion, its worldwide availability and its potential to reduce both global (CO2) and local (NOx, soot) exhaust gas emissions from conventional Diesel engines. As natural gas is consisted primarily of methane (CH4), it has high H/C ratio thus having the theoretical potential to reduce the CO2 emission by nearly 25% compared to conventional Diesel fuel. What makes dual fuel operation possible is the flammability limit between the two fuels and it exploits the advantages of each one. Diesel fuel pilot is used as a high energy ignition device (Diesel fuel pilot releases 10000 times more energy compared to the energy delivered by spark the in spark-ignition engine) while natural gas is used as a primary fuel in the operation. Several dual fuel combustion strategies have been proposed ; (a) conventional dual fuel combustion that operates with premixed natural gas which is ignited by the Diesel fuel pilot ; (b) direct injected dual fuel combustion, where both natural gas and Diesel pilot fuel are directly injected into the cylinder at the end of the compression stroke ; (c) HCCI like combustion (PCCI, RCCI) where combustion is primarily controlled by the natural gas/Diesel fuel ratio. Although dual fuel combustion has shown significant potential it still faces some challenges, among which HC and CO emission at low load and preignition and knock at high load are the major ones.