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In the cylinders of a marine diesel engine, self-ignition occurs in a very short time after the fuel injection into the combustion chamber. Therefore, this paper aims to develop a model of diesel fuel spray for the early stage of fuel spray in the marine diesel engine. The main technical aspects such as nozzle diameter of the marine engine injector and backpressure in the combustion chamber were taken into consideration.

In this paper, laboratory experimental studies were carried out to determine parameters of fuel spray in an early stage of injection in the marine diesel engine. The optical measuring Mie scattering technique was used to record the fuel injection process. The working space was a constant volume chamber. The backpressure parameters in the constant volume chamber were the same as during the operation of the marine diesel engine. Based on the experimental studies and important Hiroyasu and Arai models of fuel spray presented in literature was proposed new model of fuel spray parameters for marine diesel injectors.

In this paper, the proposed new model of the two main parameters described fuel spray evolution”: new model of spray tip penetration (STP) and spray cone angle (SCA). New model propagation of fuel STP in time was included the influence of nozzle diameter and backpressure. The proposed model has a lower error, about 15%–34%, than the model of Hiroyasu and Arai. Moreover, a new model of the evolution over time of the SCA is developed.

In the future research of fuel spray process must be taken influence of the fuel temperature. Diesel fuel has a different density and viscosity in dependence of fuel temperature. Therefore are predicted of the expansion about influence of fuel temperature, new model of fuel spray for a marine diesel engine. The main limitations occurring in the research are not possible to carry out the research while real operation marine diesel engine.

An experimental test was carried out for a real fuel injector of a marine diesel engine. Design parameters and fuel injection parameters were selected on the basis of the actual one. In the literature, SCA is defined as a constant parameter for the specific preliminary data. A new model for the early stage of fuel spray of SCA propagation in time has been proposed. The early stage of fuel spray is especially important, because in this time comes in there to fuel self-ignition.

This paper aims to gain an understanding of the behaviour of iron ore when melted by a laser beam in a continuous manner. This fundamental knowledge is essential to further develop additive manufacturing routes such as production of low cost parts and in-situ reduction of the ore during processing.

Blown powder directed energy deposition was used as the processing method. The process was observed through high-speed imaging, and computed tomography was used to analyse the specimens.

The experimental trials give preliminary results showing potential for the processability of iron ore for additive manufacturing. A large and stable melt pool is formed in spite of the inhomogeneous material used. Single and multilayer tracks could be deposited. Although smooth and even on the surface, the single layer tracks displayed porosity. In case of multilayered tracks, delamination from the substrate material and deformation can be seen. High-speed videos of the process reveal various process phenomena such as melting of ore powder during feeding, cloud formation, melt pool size, melt flow and spatter formation.

Very little literature is available that studies the possible use of ore in additive manufacturing. Although the process studied here is not industrially useable as is, it is a step towards processing cheap unprocessed material with a laser beam.

This paper aims to focus on time-constrained interactions involving industry and public actors, mainly universities, conducting research. This kind of interaction has become increasingly important to develop new pharmaceuticals, especially antibiotics. The proposed theoretical frame relies on industrial marketing and purchasing’s interactive perspective on inter-organizational relationships and especially the activities, resource, actors model, combined with key concepts on temporary organizing and project management. This study identifies the temporality and time constraints imposed by this project on public–private interactions, specific coordination tools used to create such temporality and time constraints and their consequences, including positive and negative effects for the interacting parties.

The study builds on a single in-depth qualitative case study of a major antibiotics R&D collaboration project called ENABLE.

For negative consequences, this model includes the need for constantly rebuilding trust due to fast turnover of actors, difficulties in combining resources as efficiently as possible, resource constraints, bottlenecks and neglect of some activities, such as publishing, which are normally pivotal for universities. Despite these problematic consequences of temporality, resources are rapidly made available and new competencies learned quickly. Another positive effect is the possibility to achieve complex adaptations of resources and activities even in short time frames. Importantly, projects can act as a springboard for the parties to continue collaboration and in the long term develop a continuous business relationship.

Based on the findings the authors develop a model of time-constrained inter-organizational interaction between public and private organizations.

The purpose of this study is to investigate the transport phenomena of smoke flow in a semi-open vertical shaft.

The large eddy simulation (LES) method was used to model the movement of fire-induced thermal flow in a full-scale vertical shaft. With this model, different fire locations and heat release rates (HRRs) were considered simultaneously.

It was determined that the burning intensity of the fire is enhanced when the fire attaches to the sidewall, resulting in a larger continuous flame region in the compartment and higher temperatures of the spill plume in the shaft compared to a center fire. In the initial stage of the fire with a small HRR, the buoyancy-driven spill plumes incline toward the side of the shaft opposite the window. Meanwhile, the thermal plumes are also directed away from the center of the shaft by the entrained airflow, but the inclination diminishes as HRR increases. This is because a greater HRR produces higher temperatures, resulting in a stronger buoyancy to drive smoke movement evenly in the shaft. In addition, a dimensionless equation was proposed to predict the rise-time of the smoke plume front in the shaft.

The results need to be verified with experiments.

The results could be applied for design and assessment of semi-open shafts.

This study shows the transport phenomena of smoke flow in a vertical shaft with one open side.

The purpose of this study is to determine how sonic logo’s acoustic features (intensity, pitch and pace) based on melodic tunes with no voice orient the response of consumers, attract attention, elicit levels of pleasantness and calmness and transmit brand personality traits.

A within-subject experimental factorial design is applied to measure emotional arousal (indexed as electrodermal activity) and enhancement on perceptual processing (indexed as heart rate), as well as self-reported factors, namely, calmness/excitement, pleasantness and brand personality scales.

Results show a significant increase on electrodermal activity associated with fast-paced sonic logos and a decrease in heart rate in slow-paced long sonic logos. Also, fade-up, pitch-ascending fast sonic logos are defined as more exciting and descending-pitch sonic logos as more pleasant.

The use of sonic logos with no voice does limit its implications. Besides, the use of three variables simultaneously with 18 versions of sonic logos in a laboratory setting may have driven participants to fatigue; hence, findings should be cautiously applied.

First, sonic logos are best processed in a fade-up form. Second, fast pace is recommended to orient response, whereas slow pace is recommended to transmit calmness. Practitioners may opt for fast-paced sonic logos if the design is new or played in a noisy environment and opt for slow-paced sonic logos in already highly recognized sound designs.

To the best of authors’ knowledge, this study is the first to combine psychophysiological measures and self-reported scales in a laboratory experiment on how sonic logo’s acoustic features orient response, transmit emotions and personality traits.