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orthotropic functionally graded materials using Jk-integral,Int J Solids Struct, 47 (2010) 3480-3488. [28] Yildirim B., Erdogan F., Edge crack problems in homogeneous and functionally graded materials under thermal barrier coatings under uniform thermal loading,J. Therm. Stresses, 27(4) (2004) 311-329. [29] Kosker S., Dag S., Yildirim B., Three Dimensional Modeling of Inclined Surface Cracks in FGM Coatings, Mater Sci Forum, 631-632 (2010) 109-114. [30] Dag S., Thermal fracture analysis of orthotropic functionally graded materials using an equivalent domain integral

Abstract

In this article, the static response of the functionally graded piezoelectric (FGP) plates with piezoelectric layers (sandwich FGPM) is studied based on the first order shear deformation plate theory. The plate is under mechanical, electrical and thermal loadings and finite element method is employed to obtain the solution of the equation. All mechanical, thermal and piezoelectric properties, except Poisson ratio, obey the power law distribution through the thickness. By solving the governing equation, optimum value of power law index is investigated in each type of loading. The effects of different volume fraction index, layer arrangements, various boundary conditions and different loading types, are studied on the deflection of FGPM plate. It is inferred that, the correlations between the deflection, power law index and layer arrangement are completely different in the mechanical and thermal loading and the optimum value of the power law index should be selected in each case separately. This optimum values can be used as a design criterion to build a reliable sensors and actuators in thermal environments.

Abstract

Paper presents research results of jet fuels thermal degradation exposed to different thermal loads. This problem is especially important as it influences safety of aircraft operation. Jet fuel in modern engines is used in heat transfer and cooling of different construction elements. Together with new engines’ construction and materials used thermal loads affecting jet fuel become more severe, and thus in aircraft fuel system not well understood phenomena occur, resulting with plugging injectors, valves and affecting elastomers. They affect engine operation and should be well and carefully described and understood to prevent them. Research results presented here are the first data in Poland dealing with jet fuels’ thermal degradation problem. Article is aimed to present the mechanism of jet fuel thermal degradation under different temperatures. The project has been funded by National Science Centre granted with decision no. DEC-2011/01/D/ST8/06567.

Abstract

For technical applications, a physical model capable of predicting the particle evolution in the burning process along its trajectory through the furnace is very useful. There are two major demands: all the thermo-dynamic processes that describe the particle burning process must be accounted and the model must be written in such equation terms to allow the intervention for parameter settings and particle definition. The computations were performed for the following parameters: furnace average temperature between 700 and 1200 °C, size of the sawdust particle from 4 to 6 mm and fix carbon ignition between 500 and 900 °C. The values obtained for the characteristic parameters of the burning process ranged from 30 to 60 [kg/(h·m3)] for the gravimetrical burning speed WGh and from 150 to 280 [kW/m3] for the volumetric thermal load of the furnace QV. The main conclusion was that the calculus results are in good agreement with the experimental data from the pilot installations and the real-case measurements in the sawdust working boiler furnaces or pre-burning chambers. Another very important conclusion is that the process speed variation, when the furnace temperature changes, confirms the thermo-kinetic predictions, namely that the burning process speed decreases when the furnace temperature increases.

Abstract

The paper presents results of research of the essential characteristics of two kinds of advanced coatings applied by HVOF technology. One studied coating: WB-WC-Co (60-30-10%) contains two types of hard particles (WC and WB), the second coating is eco-friendly alternative to the previously used WC-based coatings, called “green carbides” with the composition WC-FeCrAl (85-15%). In green carbides coating the heavy metals (Co, Ni, NiCr) forming the binding matrix in conventional wear-resistant coatings are replaced by more environmentally friendly matrix based on FeCrAl alloy. On the coatings was carried out: metallographic analysis, measurement of thickness, micro-hardness, adhesion, resistance to thermal cyclic loading and adhesive wear resistance (pin-on-disk test). One thermal cycle consisted of heating the coatings to 600°C, dwell for 10 minutes, and subsequently cooling on the still air. The number of thermal cycles: 10. The base material was stainless steel AISI 316L, pretreatment prior to application of the coating: blasting with white corundum, application device JP-5000.

thermal stresses in the friction discs of a multidisc wet clutch, Wear, Vol. 101, 255-271. 24. Zagrodzki P. (1990), Analysis of thermomechanical phenomena in multidisc clutches and brakes, Wear, Vol. 140, No. 2, 291-308. 25. Zhao S., Hilmas G.E., Dharani L.R. (2008), Behavior of a composite multidisk clutch subjected to mechanical and frictionally excited thermal load, Wear, Vol. 264, 1059-1068.

possible applications of annular plates: aerospace industry, mechanical and nuclear engineering, civil engineering or miniature mechanical systems the observation of their behaviours under mechanical or thermal loading is practically essential. The investigations of layered annular plates are performed for many years. The specific analyses have been carried out for the axisymmetrical case of plates in dynamic or stability issues [ 1 , 2 ]. The solution have been widened on the plate responses including the asymmetric plate modes. As the example the following works [ 3

maintain the temperature of the PV cells under 40 °C for 80 min, with a PCM RT25 that have a melt temperature of 32°C, then considering the low thermal conductivity of RT25 0.18 W.m −1 .K −1 , an internal fins in Aluminum used to transport the thermal load into the PCM in order to reduce the temperature rise on PV. In other hand Huang et al [ 8 , 9 , 10 , 11 ] investigated the use of inner fins in BIPV to enhance the heat transfer in PCM losing the excess heat in PCM. They have studied the effect of internal fins spacing on BIPV thermal regulation and PCM behavior

., Dokumentacja ruchowa i oprogramowanie stanowiska badawczego do badań procesu degradacji termicznej paliw lotniczych , Report No. 2/55/2014, AFIT. [20] Sarnecki, J., Innowacyjne stanowisko badawcze do określania stabilności termicznej paliw lotniczych , Journal of Konbin, no 1(29), pp. 15-22, 2014. [21] Sarnecki, J., Jet fuels degradation under severe thermal loads , Journal of KONBIN, no 3 (31), pp. 31-40, 2014. [22] Spychała, J., Kułaszka, A., Giewoń, J., Report No. 1/AŁ-21F3/34/2011. [23] Zurek, J., Jankowski, A., Experimental and Numerical Modelling of Combustion

REFERENCES 1. Bansal A., Ramaswamy A. (2002), FE analysis of piezo-laminate composites under thermal loads, J. Intell. Mater. Syst. Struct. , 13, 291–301. 2. Beheshti-Aval S.B., Lezgy-Nazargah M., Vidal P., Polit O. (2011), A Refined Sinus Finite Element Model for the Analysis of Piezoelectric-Laminated Beams, A Refined Sinus Finite Element Model for the Analysis of Piezoelectric-Laminated Beams, J. Intell. Mater. Syst. Struct. , 22, 203–219, https://doi.org/10.1177/1045389X10396955 . 3. Bendine K., Boukhoulda F.B., Nouari M., Satla Z. (2016), Active