International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Damage to the turbocharger of the 8400kW diesel engine, which had operated about 66 640 running hours, has caused off hire of the vessel for 10 days and the turbocharger repair had cost more than half a million euros. The study performed on this work consi sts of evaluating the consequences of the low turbocharger performance on the fuel oil consumption and the reasons for this. Specific data were collected and analysed in order to create an appropriate mathematical model between the studied parameters. Measurements and data collected were performed a month before turbocharger damage and after the TC overhaul (with new cartridge). As results can be concluded that losses in turbocharger performance is very important for the efficient operation of the main engine, they must be monitored and analysed.

The paper presents numerical analysis of air after turbocharger cooling process and its influences on the gasoline engine operating parameters. Analysis was performed with numerical 0D (zero-dimensional) simulation model by using two sets of simulations – for gasoline turbocharged engine without air cooler and for the same engine with air cooler included. Between engine rotational speeds of 1000 rpm and 5000 rpm, air cooling process increases analyzed engine developed power and engine torque up to 20.67%, increases cylinder maximum pressure up to 17.03%, increases engine volumetric efficiency up to 23.65% and reduces brake specific fuel consumption up to 1.32% when compared with the same engine without air cooler. At the highest engine rotational speeds (between 5000 rpm and 6000 rpm) it was observed that selected air cooler does not offer the required and expected performance, so air cooling process in this engine operating area can and should be improved.

Numerical investigation of naturally aspirated gasoline engine main operating parameters and engine upgrade with a turbocharger is presented in this paper. Analysis is performed by using numerical 0D (zero-dimensional) simulation model. Turbocharging process with a selected turbocharger increases engine maximum torque for 62.58 % and also increases maximum engine effective power for 58.82 %. One of the main reasons of turbocharging process usage is reduction of engine brake specific fuel consumption. The highest decrease in brake specific fuel consumption for a turbocharged engine, in comparison with naturally aspirated one, is obtained at 4000 rpm and amounts 8.83 g/kWh (from 239.01 g/kWh for naturally aspirated engine to 230.18 g/kWh for a turbocharged engine). Turbocharging process brings several useful benefits to the analyzed gasoline engine, which is also a valid conclusion for internal combustion engines in general.

A change in essential operating parameters of a high speed direct injection turbocharged diesel engine MAN D0826 LOH15 during the injected fuel mass flow variation was presented. Based on two measurement sets, performed with standard diesel fuel, several operating parameters were calculated: engine torque, effective power, excess air ratio, specific effective fuel consumption and heat released per engine process. All of the calculated parameters are presented for a wide engine operating range. Along with calculated, several important parameters were measured, in addition to those presented in measurement sets. Additional measured parameters were lubrication oil temperature and exhaust gas temperature before and after the turbocharger turbine. Those calculated and measured parameters allow deep insight not just into the engine process, but also in the process of turbocharging, which is very important in the analyzed diesel engine operation.