Biomass usage in CHP units

This article deals with overview of biomass usage in combined heat and power units (CHP). The aim of the paper is to explain fundamentals of CHP units and heat and power generation with these units. Article deals also with basic requirements for connecting these blocks into power grid and differences in operation between decentralised CHP units and centralised power plants. In beginning of article the authors devote about basic principles of extraction fuel from biomass and with processing of biomass

ВИКОРИСТАННЯ ТЕХНІКИ ВІЗУАЛІЗАЦІЇ ЗВУКУ ДЛЯ ВИЯВЛЕННЯ ТА АНАЛІЗУ ДЖЕРЕЛ ШУМУ ТРАНСПОРТНОГО ЗАСОБУ

Urgency of the research. The use of continuous measurement on the roads and highways with noise visualization techniques can in the future lead to increasing road safety. Central computer system could for example, evaluate the information continuously and the feedback would have warned drivers, through their mobile phones or GPS, to replace tires in the nearest dealer or car service. Vehicles fault diagnosis is currently carried out by different devices in car services. In terms of increasing the efficiency, diagnostic methods can be extended for noise visualization techniques.Target setting. Using of measuring devices (for noise visualization) in car services for faster detection of faults and damaged parts as well as based on the measured values of noise pressure level, could be evaluated, if the tires are still safe or not.Actual scientific researches and issues analysis. Acoustic cameras and various noise visualization techniques are implemented to manufacturing process of passenger car manufacturers. Their use is for detecting errors and for reduction of engine noise and its parts as well as car interior.Uninvestigated parts of general matters defining. This article provides only partial research and conclusions. Philosophy, to use this noise visualization technique in many cases is different.The research objective. The aim of this study was to demonstrate the differences in sound levels between two vehicles Skoda Octavia at different speeds at the same road. Partial output is a frequency analysis and identification of dominant sound sources in the engine space of VW Golf 1.4 vehicle.The statement of basic materials. The methods of dynamic visualization of noise are used all around the world. In our case, we used the acoustic camera to visualize and identify the sound sources of moving vehicle as well sources of noise in the engine space.Conclusions. It has been found that vibration from the engine are transmit by chassis to the interior of vehicle and cause uncomfortable noise. In the future, we expect the use of such measuring devices in car services for faster detection of faults and damaged parts. When passing vehicles and higher speeds, the biggest noise, the pressure wave in the contact tire-road is causing. Differences in noise pressure levels are mainly due to weight, quality of tires, aerodynamics and the shape and size of the tread.В данной статье рассматривается метод динамической визуализации шума, используя акустическую камеру. Использование акустической камеры дает возможность визуализировать и идентифицировать источники звука движущейся техники, а так же источники шума в моторном отсеке. Для того чтобы лучше диагностировать дефекты, можно данные измерения совмещать с измерениями вибрационных сенсоров. Результат исследования показал разницу в уровне звуков между двумя машинами Skoda Octavia на одной и той же дороге при разных скоростях. Частичный вывод – это анализ частоты и идентификация доминирующих источников звука в моторном отсеке VW Golf с объемом двигателя 1,4 л.У цій статті розглянуто метод динамічної візуалізації шуму, використовуючи акустичну камеру. Використання акустичної камери дає можливість візуалізувати й ідентифікувати джерела звуку рухомої техніки, а так само джерела шуму в моторному відсіку. Для того щоб краще діагностувати дефекти, можна дані вимірювання поєднувати з вимірами вібраційних сенсорів. Результат дослідження показав різницю у рівні звуків між двома машинами Skoda Octavia на тій самій дорозі при різних швидкостях. Частковий висновок – це аналіз частоти та ідентифікація домінуючих джерел звуку в моторному відсіку VW Golf з об’ємом двигуна 1,4 л

Economic evaluation of biogas plant

This paper deals with problematic of biogas plants. Economical evaluation of biogas plant will be described

РОЗРАХУНОК ЕФЕКТИВНОСТІ ЕКРАНІЗУВАННЯ БУДІВЕЛЬНИХ МАТЕРІАЛІВ НА ОСНОВІ МОДЕЛЮВАННЯ РОЗКЛАДУ ЕЛЕКТРОМАГНІТНОГО ПОЛЯ

This paper deals with modelling the penetration and absorption of high frequency electromagnetic field through the building material. It is focused on distribution of electromagnetic field in frequency range from 1.5 to 5.0 GHz, penetrating through the building material of different thickness. Nowadays in some domestic appliances and wide area exists a lot of electric and electronic devices, which are the sources of electromagnetic interference. To protect against electromagnetic interference in first case is important design concept of the devices, and some additional protection can be represented by construction works of rooms or building. For this reason, the article sets out to evaluate the shielding effectiveness and absorption of specific building materials in term of their harmful effect on the human body. Simulation of the penetration of HF electromagnetic field is created in the ANSYS HFSS.Рассмотрено моделирование проникания и поглощения высокочастотного электромагнитного поля строительными материалами. Основное внимание уделяется распределению электромагнитного поля, проникающего через строительные материалы разных свойств в частотном диапазоне од 1,5 до 5 ГГц. В настоящее время существует целый ряд электрического и электронного оборудования, которое является источником электромагнитных помех. Чтобы свести к минимуму помехи, при разработке этого оборудования очень важно правильно спроектировать конструкцию, причем дополнительную защиту можно обеспечить с помощью достаточного экранирования отдельных частей оборудования. С учетом вышеизложенного, проведена оценка эффективности экранирования определенных строительных материалов и их комбинаций с целью повышения его эффективности. Симуляции были произведены на программном комплексе ANSYS HFSS.Розглянуто моделювання проникнення і поглинання високочастотного електромагнітного поля будівельними матеріалами. Основна увага зосереджена на поширенні електромагнітного поля, що проникає через будівельні матеріали з різними характеристиками в діапазоні частот від 1,5 до 5 ГГц. Нині є багато електричного і електронного обладнання, яке є джерелом електромагнітних завад. Щоб звести до мінімуму це втручання, дуже важливо правильно спроектувати конструкцію, причому додатковий захист можна забезпечити зо допомогою екранування окремих частин обладнання. З урахуванням вищевикладеного, проведено оцінювання ефективності екранування на певних будівельних матеріалах і їх комбінацій з метою підвищення ефективності екранування. Розрахунки проводилися у програмному комплексі ANSYS HFSS

Overview of biomass usage in combined heat and power units

This article deals with overview of biomass usage in combined heat and power units (CHP). The aim of the paper is to explain fundamentals and basic properties of these units and heat and power generation with these units. Article deals also with basic requirements for connecting these blocks into power grid and differences in operation between decentralised CHP units and centralised power plants. In beginning of article the authors devote about basic principles of extraction fuel from biomass and with processing of biomass. Decentralised units are introduced also on examples of onsite solutions of these units

Renewable energy sources - biogas plants

This paper deals with problematic of biogas plants.Biogas plants are an appropriate decentralized resource in light of the stability of electricity supply and feedback effects on the power system. Combined production heat and power can compete conventional sources in terms of the cost effectiveness of investment and thus to ensure a sustainable low-carbon energy

Measuring of Shielding Effectiveness of Electromagnetic Field of Polystyrene in the Frequency Range from 1 GHz to 9 GHz

This paper deals with measurement of the shielding effectiveness against the electromagnetic field. Shielding effectiveness against the electromagnetic field characterizes property of material to penetrate the electromagnetic field. Measuring of shielding effectiveness was performed in the frequency range from 1 GHz to 9 GHz with a step of 0.2 GHz. Measurement was performed in non-reflection chamber. Measured objects were the construction materials: Styrodur polystyrene with thickness of 50 mm, Styrodur polystyrene with thickness of 25mm and their combination. The result of measurement is comparation of shielding effectiveness of shielding objects.

Operation of hydropower plants in Slovakia

This paper deals about hydropower plants in Slovakia. Hydropower is the most used renewable energy source for electricity in the Slovak Republic. Hydro potential of rivers is used to generate electrical energy, which is permanently renewing and inexhaustible primary energy source

ASSESSMENT OF THE WASHING MACHINES SOUND QUALITY BY THE BINAURAL MEASUREMENT SYSTEMS

The target and goal of psychoacoustics is to understand how people perceive and experience different sounds. Psychoacoustic is joining the field of acoustic and psychology. Sound quality is a perceptual reaction to the sound that reflects the listener’s reaction

Impact of the renewable energy sources on long-term dynamic in the Slovak power system

This paper discuss about long-term dynamics simplified model of the power system. This model represents Slovak power system connected trough inter-tie line to interconnected power system – ENTSO-E. The Slovak power system itself is represented by node SEPS. To this node conventional and renewable energy sources are connected. The significant growth of installed power capacity of renewable energy sources (RES) in the last few years may cause incidental disturbance of power balance in the power system. This problem is typical for photovoltaic power stations. It is very hard to predict photovoltaic (PV) power production especially during cloudy weather conditions. Because of this fact it is very important to determine maximum share of RES in each power system. This paper deals with impact of PV in power system