Optimization of a storage water heater construction

W artykule przedstawiono optymalizację elementów konstrukcji pojemnościowego ogrzewacza wody. Kryteria optymalizacji to minimalizacja zużycia energii oraz kosztów materiałowych elementów konstrukcyjnych ogrzewacza, decydujących o zużyciu energii. Rozwiązania Pareto-optymalne przedstawione są w postaci punktów, które decydują o wartościach pięciu zmiennych decyzyjnych. Przedstawiony algorytm optymalizacyjny może posłużyć do wspomagania konstruowania optymalnych w sensie kosztów wytworzenia i energooszczędności pojemnościowych urządzeń grzewczych.The paper presents optimization of elements in a storage water heater construction. Two optimization criteria are taken into account: energy saving and minimum costs of materials, used in the construction of a water heater. The construction elements used in a heater have significant influence on the value of energy consumption. Basic construction elements of the storage water heater are shortly described. Fundamental physical and mechanical properties of selected materials used in a thermal insulation of the heaters are shown. The optimization task is delineated and an object of the optimization is also schematically presented. Additionally, the paper contains a mathematical model of the optimization and a range of decision variables. The Pareto-optimal solution points are calculated. These points decide on the values of five decision variables. When designing the storage water heater appliances, these optimization algorithms can be used to get the optimal material costs and energy saving. The paper is strictly focused on the cost of the materials used, not the cost of the heater manufacturing itself. Additional costs can be added by processing the considered material, for example polyurethane foam or by performing foamed polystyrene molders - properly to heater dimensions. The scale of additional costs surely depends on an output volume and technical capacities of a manufacturing plant - for example the size of machine park. Additional costs related to specific construction materials can be analyzed in other, individual consideration

Parametric identification of storage water heater model

W pracy przedstawiono analizę modelu fizycznego i matematycznego pojemnościowego ogrzewacza wody. Rozwiązanie modelu matematycznego zostało porównane z wynikami badań eksperymentalnych. Za pomocą aproksymacji wyników badań eksperymentalnych otrzymano wartości współczynników przenikania ciepła dla ogrzewaczy o dwu różnych pojemnościach. Badania tego typu pozwalają na określenie efektywności energetycznej dowolnego ogrzewacza pojemnościowego, gdyż wartość współczynnika przenikania ciepła stanowi o jakości termoizolacji zbiornika z ciepłą wodą użytkową.The paper presents physical and mathematical model of a storage water heater. Typical structure of storage water heater is also included in the article (Chapter 2, Fig.1). The analytical solution of mathematical model was compared with results of an experimental research. With the help of an approximation of experimental results, values of heat transmission coefficients for two different size storage water heaters were received. Such investigations allow to specify the energy effectiveness for any storage water system, because the heat transmission coefficient value determines the thermal insulation quality of a tank filled with a warm drinking water. Due to growing a global power demand, it is necessary to select such devices, which losses of energy are as low as possible. Nevertheless, the proposed methodology can't be used for evaluating the heat transmission coefficient of any storage water system only in the basis of the computer simulation results. Many structures of the storage water systems are characterized by different system parameters, such as: the thickness of isolation layer, the material of isolation layer, the thickness and material of chamber walls, the material of storage water enclosure, etc. Therefore the numerical investigations have to be performed together with the experimental researches in order to identify the system parameters for different structures of the storage water systems

The GnRH analogues affect novel neuropeptide SMIM20/phoenixin and GPR173 receptor expressions in the female rat hypothalamic–pituitary–gonadal (HPG) axis

The recently discovered peptide phoenixin (PNX) and its receptor GPR173 are novel factors that exhibit a large spectrum of regulatory activity, especially when considered as a central modulator of GnRH-related hormonal control of reproductive processes. It has been already proven that GnRH agonists and antagonists can modulate peptidergic signalling in the HPG axis. Despite these findings, there is so far no information regarding the influence of treatment with GnRH analogues on SMIM20/phoenixin signalling in the hypothalamic–pituitary–gonadal axis. In the current study, SMIM20/phoenixin and GPR173 mRNA levels were measured in the hypothalamus, pituitary and ovaries of female rats in the dioestrus phase following treatment with GnRH-R agonist (buserelin) and antagonist (cetrorelix) using quantitative real-time PCR. The serum PNX concentrations were also estimated with ELISA technique. The hypothalamic, hypophyseal and especially ovarian levels of SMIM20 mRNA were increased after both buserelin and cetrorelix administration. The GPR173 expressions were in turn decreased in the hypothalamus and pituitary. Treatment with the GnRH analogues led to the modulation of SMIM20/phoenixin and GPR173 mRNA expression in the female rat hypothalamic–pituitary–gonadal axis. By identifying buserelin and cetrorelix as novel modulators of phoenixin signalling in the animal HPG axis, these results cast new light on the GnRH analogues mode of action and contribute to a better understanding of the mechanisms responsible for the hormonal control of reproduction. © 2019 John Wiley & Sons Australia, Lt

Novel ureidopropanamide based N-formyl peptide receptor 2 (FPR2) agonists with potential application for central nervous system disorders characterized by neuroinflammation

Formyl peptide receptor2 (FPR2) is a G-protein coupled receptor that plays critical roles in inflammatory reactions. FPR2-specific interaction can be possibly used to facilitate the resolution of pathological inflammatory responses by enhancing endogenous anti-inflammation systems. Starting from our lead agonist 5, we designed new ureidopropanamides derivatives able to activate FPR2 in transfected cells and human neutrophils. The new FPR2 agonists showed good stability towards oxidative metabolism in vitro. Moreover, selected compounds showed anti-inflammatory properties in LPS-stimulated rat primary microglial cells. (S)-3-(4-Cyanophenyl)-N-[[1-(3-chloro-4-fluorophenyl)cyclopropyl]methyl]-2-[3-(4-fluorophenyl)ureido]propanamide ((S)-17) emerged as prospective pharmacological tool to study the effects of FPR2 activation in the central nervous system (CNS) being able to reduce IL-1β and TNF-α levels in LPS-stimulated microglial cells and showing good permeation rate in hCMEC/D3 cells, an in vitro model of blood brain barrier. These results are very promising and can open new therapeutic perspectives in the treatment of CNS disorders characterized by neuroinflammation