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Simulation of polymer injection molding: A new practical approach to improve computation Accuracy

Narowski P., Wilczynski K.

Challenges of Modern Technology

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2016

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Vol. 7, no. 3

25--28

EN

Simulation of injection molding of polymeric materials is still a series scientific and engineering problem. The quality of the input data is crucial for computation accuracy. The original, relatively simple tool has been designed to validate simulations. This allows a fast identification of the critical input data, and next their proper adjustment to computations. FEM simulations have been compared with directly registered pictures of cavity filling process in a special injection mold with a sight-glass.

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Methodology for generating stable concentrations of nano-objects

Kaczorowska B.

Challenges of Modern Technology

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2016

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Vol. 7, no. 3

20--24

EN

With an increasing number of companies using and producing nanomaterials, also the number of workers who are exposed to nano-objects is increasing. Nano-objects, because of their very small size, can very easily overcome the human systemic barrier and rapidly penetrate into the body, settling mainly in the lungs. It is important to establish standards for nanomaterials, because of the health and safety of workers who are exposed to nanomaterials in their workplace. During the exposure evaluation, it is important to determine the parameters of nano-objects in real-time and thus it is necessary to validate the measuring apparatus used during researches. The purpose of the project is to provide the possibility of obtaining stable concentrations of the nano-objects to validate the measuring apparatus for real-time testing of parameters of the nano-objects. The literature review [1-4] on methodology for generating nano-objects using techniques of nucleation and spark discharge was made. After analyzing different models, which were found in the literature [1-4], an experimental set-up was created. The experimental set-up is composed of: an aerosol generator, an aerosol neutralizer, a high-temperature furnace, a heat exchanger, a dilution system and a sampling chamber. Our set-up has many advantages: –– it can generate different types of nano-objects (carbon, cooper and silver nano-objects) with stable concentration; –– it can generate nano-objects with different concentration; –– it allows to take four samples at the same time and measure their parameters by using various measurement apparatus. Thanks to the built set-up, it will be possible to validate measuring apparatus for testing parameters of nano-objects in real-time using an ELPI+ (Dekati) as a reference apparatus.

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The influence of RME on mass and number concentration of nano PM in exhaust gases from a diesel engine

Cisek J.

Journal of KONES

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2014

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Vol. 21, No. 2

53--60

EN

Transport is a major source of the particle pollution (PM). Combustion engine particulate emissions have the potential cause adverse health effects. These effects include cancer and other pulmonary and cardiovascular diseases. A substantial proportion of the number of particles, but not the mass, is ultrafine. For example – one million particles of 100 nanometers size with a unit density of 1 g/cm3 have a mass of approximately 0.0005 g. The paper includes research results of mass and number concentration of nanoPM for 1.9 TDI VW exhaust gases fuelled by standard diesel. The measurements were performed for ambient air and 3 different point of engine work (idle speed, low and high load at 2000 rpm). For nanoPM measurements was used Electrical Low Pressure Impactor ELPI from DECATI, was found, among other things, that the biggest mass concentration was at 0.1-10 μm of PM diameter but the biggest number concentration was at 0,01 – 0,1 μm and thus for the size of solid particles of at least an order of magnitude smaller than the mass concentration. The biggest the negative differences in the mass concentration occur in the exhaust gases of the RME fuelled engine (in comparison with diesel fuel) at engine idling when the smallest injection pressure and temperature inside the engine cylinder exist and the oxygen availability is also the lowest (because of the small charging pressure and high EGR rate). Such measurements are important not only in terms of utilitarian but also in cognitive sense – for determining the effect of the engine construction parameters and/or regulating the engine (or the fuel composition) on the mass and the number of nanoparticles emitted in the exhaust gases.