The development of technology and design of light management systems remains dynamic. Among all the benefits offered by these systems, the most valuable might definitely be the possibility of saving energy consumption. Knowing the value of energy savings is the key factor that users need to know before deciding to use a lighting management system (the type of light management system). For this purpose, it is useful to simulate the operation of the lighting control system, for example in the DIALux program. Such simulation helps evaluate potential savings in electricity consumption using the proposed lighting control system. In the DIALux program, it is possible to change the luminous flux value of luminaires. In such a case, it becomes possible to semi-simulate the light management system’s operation as we don’t receive actual information on reducing installed power of the lighting system during reduction of the luminous flux value of luminaires. This article shows what type of technical data are important to use for the DIALux program to properly and accurately simulate light management systems and to receive accurate data on energy saving. It also presents the results of photometrical and electric parameter measurements (Φ – luminous flux, P – power, PF – power factor, THDi – total harmonic distortion of current). The article discusses the power control characteristics obtained on the basis of these measurements and explores the source of differences between simulation of energy saving calculations and real measured energy savings. An existing lighting control system installed in an office reception area was used to compare calculations with the real value of energy consumption reduction. The impact of electronic power and control systems on electrical network parameters is also an important problem mentioned in this article. It also explores the effect of power regulation of LED luminaires and LED modules on the value of the power factor and total harmonic distortion (current) value (THDi).
Ice-cored moraines are the only accumulation forms of Antarctic ice-sheet in the contact zone with Bunger Hills. Their longiness ranges from 3.5 km to 250 m, they are from 300 m to 30 m wide and their elevation oscillates between 10 and 5 m. A thickness of moraimc cover which lags the ice-core is changeable in the limit of 1 m. A process of decay of ice-cores, leading to deformations of their moraines, plays a small part up to now. It is caused a dry climate, probably, which was not favorable for the release and the work of melted waters in a large scale. The weak separation of ice-cored moraines results from a small amount of morainic material transported to the front of ice-sheet, probably as the ice-sheet is almost motionless. The granulometric analysis of morainic sediments shows their bad segregation.
The article deals with the process of restoring life into the Elblag’s waterfront – located in the heart of the city, which is the Old Town with still forgotten Granary Island, both damaged by the second world war. The conclusions are inspired by publications about Elblag deriving from various periods, as well by international or students’ workshops. The author describes various considerations how to bring Granary Island into cultivation simultaneously with rebuilding Elblag’s Old Town, that derive from the conservation concept based on a new method named retroversion, how to create new panorama of the waterfront and what is the best way to integrate it with The Old Town, using Elblag River.
The authors presented problems related to utilization of exhaust gases of the gas turbine unit for production of electricity in an Organic Rankine Cycle (ORC) power plant. The study shows that the thermal coupling of ORC cycle with a gas turbine unit improves the efficiency of the system. The undertaken analysis concerned four the so called "dry" organic fluids: benzene, cyclohexane, decane and toluene. The paper also presents the way how to improve thermal efficiency of Clausius-Rankine cycle in ORC power plant. This method depends on applying heat regeneration in ORC cycle, which involves pre-heating the organic fluid via vapour leaving the ORC turbine. As calculations showed this solution allows to considerably raise the thermal efficiency of Clausius-Rankine cycle.
The paper presents studies of mathematical modelling in transonic flow through the first stage rotor of the axial compressor of homogenous and heterogeneous condensation. The condensation phenomena implemented into a commercial software is based on the classical theory of nucleation and molecular-kinetic droplet growth model. Model is validated against experimental studies available in the literature regarding the flow through the first stage of turbine compressor, i.e. the rotor37 transonic compressor benchmark test. The impact of air humidity and air contamination on the condensation process for different flow conditions is examined. The influence of latent heat release due to condensation exerts a significant impact on the flow structure, thus the analysis of the air humidity and contamination influence on the condensation is presented. The results presented indicate the non-negligible influence of air humidity on the flow structure in the transonic flow regime, thus it is recommended to take condensation phenomenon under consideration in high-velocity airflow simulations.