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Increasing the efficiency of IC engines is a frequently discussed topic, and one of the approaches taken is to modify the thermodynamic work cycle of the engine so that it resembles the ideal cycle more closely. This paper attempts to achieve that by altering the kinematics of the piston-crank mechanism by introducing an epicyclic non-circular gear train between the crank and the flywheel. The addition of the non-circular gears alters the work cycle by introducing a state of dwell during key points of the cycle. Possible gear shape solutions were calculated using a known, periodic function to express the gear transmission ratio. The final result was an epicyclic non-circular gear train that has a noticeable effect on the kinematics of the piston-crank mechanism resulting in an increase of the engines work cycle efficiency.

Despite significant achievements in the diesel engines starting characteristics improvement, there are still problems associated with unstable ignition, poor combustion of fuel during start-up and subsequent warm-up. For the conditions of a diesel engine’s cold start, the characteristics of the fuel burnout, heat generation, and thermal management are determined. The inaccuracy in the cylinder pressure measuring was calculated. The patterns of fuel burnup, obtained on the basis of the experimental pressure diagrams analysis, make it possible to obtain a good agreement between the calculated and experimental results. The influence of the start-up conditions, including the increase in the intake air temperature, on the magnitude of the kinetic indicators of combustion characteristics and the completeness of combustion of fuel is established.

Recently, “Maximum Achievable Control Technology” (MACT) floor regulations have been implemented in the US for total fugitive particulates from aluminium smelter potlines; similar regulations also now apply in Canada and the EU. These highlight the challenge that smelters face in meeting increasingly stringent air quality limits. For any pollutant, the first step in establishing an effective mitigation strategy is understanding the key sources of emissions. Here we report the results of a time-resolved study that examined the response of fugitive dust emissions to operations in the potroom over an entire work cycle. Identical sets of real-time dust monitors were located at both the potroom roof and floor level between cells. This built upon an earlier study on the composition of potroom dust, involving several prebake point-fed technology smelters. Similar to fugitive HF, it was found that the changing of prebaked anodes was a major contributor to fugitive dust in the potroom. At this potline, other contributors to fugitive roof dust include metal tapping, loading of cover material and mechanical sweeper vehicle movements. As expected, operations related to solids handling/transport were found to release only fugitive dust, with minimal HF emission.

Indian plastic processing industry comprises of Micro, Small and Medium Enterprises (MSMEs). Manual labor and locally designed workplace fixtures are observed in shop-floor workstations. Aim of present research was to identify incidence of musculoskeletal ailments and awkward working postures among workers in the granulator workstation and propose design modifications from physical ergonomics perspective. Combination of research techniques comprising of questionnaire study, postural assessment tools, statistical analysis, digital human modeling and method study were utilized to accomplish the stated objective. Significant occurrence of body part discomfort was observed. Workstation accessories designs were not in accordance with recommended guidelines. Workstation design and work methods were found incompatible with worker’s anthropometry and thus led to the prevalence of awkward working postures. Redesign of workstation accessories and subsequent modification of work methods, enabled improvement of working postures and reduction of work elements. Research methodology demonstrated in present study may be adopted by engineers/managers/supervisors in MSMEs towards implementing context specific human centric production systems.

The paper presents a new approach of wall conveyor engines diagnosis. A wall conveyor is an essential device in coal mines. Its work is usually represented by three time series of current values of three conveyor engines. The startup of the conveyor is the phase with the maximal observed load during its work cycle. In the research, each startup is described with almost twenty variables. On the basis of 1000 real monitored startups, a set of association rules was inducted. On the basis of the further rules analysis and interpretation, a set of almost 50 rules was selected to the diagnosis system. The proposed diagnosis system compares the quality (precision) of each association rule from a selected subset—the precision evaluated on the representative data—with the precision of the same rule, evaluated on newly detected startups.