scholarly journals Influence of Selected Factors on the Duration and Energy Efficiency of Autoclave Steaming Regimes of Non-Frozen Prisms for Veneer Production

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 7433
Author(s):  
Nencho Deliiski ◽  
Ladislav Dzurenda ◽  
Dimitar Angelski ◽  
Natalia Tumbarkova
Keyword(s):  
Energy Efficiency ◽  
Moisture Content ◽  
Cross Section ◽  
Steam Generator ◽  
Atmospheric Pressure ◽  
Energy Efficient ◽  
Initial Temperature ◽  
Heat Power ◽  
Wood Moisture ◽  
Loading Level

This paper puts forward a methodology for calculating the duration and energy efficiency of regimes for autoclave steaming of wooden prisms for veneer production at limited heat power of the steam generator, depending on the dimensions of the prism’s cross section, wood moisture content, and loading level of the autoclave. The methodology is based on the use of two personal mathematical models: the 2D non-linear model of the temperature distribution in non-frozen wooden prisms subjected to steaming and subsequent conditioning in an air medium, and the model of the non-stationary heat balance of autoclaves for steaming wood materials. Using the suggested methodology, the calculation and research into the duration and energy efficiency of regimes for heating of beech prisms have been carried out. The variables used were an initial temperature of 0 °C, cross-section dimensions 0.3 × 0.3 m, 0.4 × 0.4 m, and 0.5 × 0.5 m, moisture content of 0.4, 0.6, and 0.8 kg·kg−1, during their steaming in an autoclave with a diameter of 2.4 m, length of 9.0 m and loading level of 40, 50, and 60% at a limited heat power of the steam generator, equal to 500 kW. It has been determined that the duration of the autoclave steaming regimes, at a loading level of 50% being most often used in the practice beech prisms with moisture of 0.6 kg·kg−1, does not exceed 9 h, 13 h, and 20 h for prisms with cross-section 0.3 × 0.3 m, 0.4 × 0.4 m, and 0.5 × 0.5 m, respectively. This duration is less than half of the corresponding duration of the steaming regimes at atmospheric pressure. The energy needed for warming up such prisms themselves does not exceed 60, 65, and 69 kWh·m−3, respectively, and the energy consumption of the whole autoclave then is equal to about 90, 99, and 105 kWh·m−3, respectively. The energy efficiency of the autoclave steaming regimes changes between 62.2% and 68.8% for the studied ranges of the influencing factors and it turns out to be more than 2–3 times larger in comparison with the efficiency of the steaming at atmospheric pressure. The methodology can be used for various calculations with ANSYS and to create the software for systems used for computing and model-based automatic realization of energy-efficient regimes for autoclave steaming of different wood materials from various species. This could be useful in developing similar methodologies in different areas of thermal treatment at increased pressure of various capillary-porous materials of plant or technical origin.

scholarly journals Computing the heat flux required for warming up of frozen wooden prisms for veneer production in the beginning of their autoclave steaming

2021 ◽  
Vol 1208 (1) ◽  
pp. 012021
Author(s):  
Nencho Deliiski ◽  
Dimitar Angelski
Keyword(s):  
Heat Flux ◽  
Moisture Content ◽  
Steam Generator ◽  
Heat Fluxes ◽  
Heat Power ◽  
Wood Moisture ◽  
Medium Temperature ◽  
Suggested Approach ◽  
Loading Level ◽  
In The Beginning

Abstract An approach for computing the heat flux required for warming up of frozen wooden prisms in the regimes for their autoclave steaming at limited heat power of the steam generator, depending on the dimensions of the prisms cross section, wood moisture content, and loading level of the autoclave has been suggested. The approach is based on the use of two personal mathematical models: 2D non-linear model of the temperature distribution in subjected to steaming frozen wooden prisms and model of the non-stationary heat balance of autoclaves for steaming wood materials. For numerical solving of the models and practical application of the suggested approach, a software program was prepared in the calculation environment of Visual FORTRAN Professional developed by Microsoft. Using this program computation and research of the non-stationary change of the processing medium temperature and heat fluxes in an autoclave with a diameter of 2.4 m, length of 9.0 m and loading level of 50% at a limited heat power of the steam generator, equal to 500 kW during the initial part of the steaming in it of frozen beech prisms with different moisture content have been carried out. The suggested approach can be used for computing and model based automatic realization of energy efficient optimized regimes for autoclave steaming of different wood materials.

Electric resistivity tomography shows radial variation of electrolytes in Quercus robur

2010 ◽  
Vol 40 (6) ◽  
pp. 1189-1193 ◽  
Author(s):  
Dirk Bieker ◽  
Steffen Rust
Keyword(s):  
Moisture Content ◽  
Cross Section ◽  
Cross Sections ◽  
Quercus Robur ◽  
Distinct Pattern ◽  
Electric Resistivity ◽  
Wood Moisture Content ◽  
Wood Moisture ◽  
Resistivity Tomography ◽  
English Oak

Electric resistivity tomograms of English oak ( Quercus robur L.) show a very distinct pattern of electric resistivity that has not been found in any other tree species yet and that cannot be related to the distribution of wood moisture content over the stem cross section. To reveal the factors underlying this two-dimensional pattern of electric resistivity, the variation of specific gravity and wood moisture content was analyzed in 18 cross sections of six roadside English oak trees after electric resistivity tomography. pH and electrolyte content were analyzed in two representative cross sections. Results show that electric resistivity correlates neither with wood moisture content nor density. The steep increase in electric resistivity at the sapwood–heartwood boundary correlates well with decreasing pH, potassium, and magnesium. The decreasing electric resistivity within the heartwood of English oak correlates with potassium and magnesium, increasing from the sapwood–heartwood boundary to the pith. More research is needed to identify species-specific electric resistivity patterns and their main factors if the method is to be used to detect wood fungal decay, historical ground water contamination, or other influences that may change the pattern of electric resistivity in the stem cross section.

scholarly journals Moisture distribution over tree trunk cross-section in bilberry spruce forests

2021 ◽  
Vol 25 (2) ◽  
pp. 35-40
Author(s):  
P.A. Feklistov ◽  
◽  
A.V. Gryazkin ◽  
I.N. Bolotov ◽  
O.N. Tyukavina ◽  
...  
Keyword(s):  
Moisture Content ◽  
Water Supply ◽  
Cross Section ◽  
Wood Moisture Content ◽  
Moisture Distribution ◽  
Age Classes ◽  
Wood Moisture ◽  
Spruce Forests ◽  
Significant Difference ◽  
The Cross

The article considers the change in the moisture content in the wood along the cross-section of spruce trunks, it also analyzes the influence of the trees age and the diameter of the trunk on the wood moisture content. The research was carried out in the Arkhangelsk Forestry in the bilberry spruce forests of different age classes (from IV to VIII). 10 trial plots were laid in clear stands or with a small mixture of birch and pine. To study the moisture content of spruce trunks, 15 sample trees (150 in total) were selected for each trial plot. The wood moisture content was determined on cores sequentially divided into 5-millimeter segments. Wood samples were weighed on a VT-500 torsion balance and dried in a drying cabinet at a temperature of 105 °C to a completely dry state. The relative moisture of wood was calculated. As a result of the conducted studies, the moisture of sapwood (from 44,8 to 45,9 %) and heartwood (from 32,2 to 36,1 %) was established. Two models of changes in the amount of water at different distances from the cambium were identified. The majority of trees (78–98 %) are characterized by a well-defined water supply zone, the moisture content of which is maximum at a distance of up to 25 mm from the cambium, after which it decreases sharply. The water supply zone is represented by approximately 40...50 outer annual rings. The second model is characterized by a gradual decrease in wood moisture along the radius from the periphery to the center of the trunk. Such a model of changes in the moisture content of wood in the cross-section of the trunk is rare, mainly in young trees. As the trunk diameter increases, the moisture content of sapwood decreases. There was no significant difference in the sapwood moisture of spruce trunks of different age classes. The sapwood moisture decreases from the root neck to 1.5 m in height of the trunk, varying from 52...53 % to 49,0...49,5 %.

Examination of moisture content variation within an operational wet deck

TAPPI Journal ◽  
2013 ◽  
Vol 12 (1) ◽  
pp. 45-50 ◽  
Author(s):  
LAURENCE SCHIMLECK ◽  
KIM LOVE-MYERS ◽  
JOE SANDERS ◽  
HEATH RAYBON ◽  
RICHARD DANIELS ◽  
...  
Keyword(s):  
Moisture Content ◽  
Southeastern United States ◽  
Forest Products ◽  
Time Domain Reflectometry ◽  
Water Application ◽  
Wood Moisture ◽  
International Paper ◽  
Content Variation ◽  
Moisture Variation

Many forest products companies in the southeastern United States store large volumes of roundwood under wet storage. Log quality depends on maintaining a high and constant wood moisture content; however, limited knowledge exists regarding moisture variation within individual logs, and within wet decks as a whole, making it impossible to recommend appropriate water application strategies. To better understand moisture variation within a wet deck, time domain reflectometry (TDR) was used to monitor the moisture variation of 30 southern pine logs over an 11-week period for a wet deck at the International Paper McBean woodyard. Three 125 mm long TDR probes were inserted into each log (before the deck was built) at 3, 4.5, and 7.5 m from the butt. The position of each log within the stack was also recorded. Mixed-effects analysis of variance (ANOVA) was used to examine moisture variation over the study period. Moisture content varied within the log, while position within the stack was generally not significant. The performance of the TDR probes was consistent throughout the study, indicating that they would be suitable for long term (e.g., 12 months) monitoring.

Analysis Criteria for Choosing Energy Efficient High-Quality Light Sources and Luminaires

2018 ◽  
pp. 113-119
Author(s):  
Gennady Ya. Vagin ◽  
Eugene B. Solntsev ◽  
Oleg Yu. Malafeev
Keyword(s):  
Energy Efficiency ◽  
Energy Efficient ◽  
National Standards ◽  
Light Sources ◽  
The European Union ◽  
High Quality ◽  
Eu Directive ◽  
The World ◽  
A New Technique ◽  
Energy Labelling

The article analyses critera applying to the choice of energy efficient high quality light sources and luminaires, which are used in Russian domestic and international practice. It is found that national standards GOST P 54993–2012 and GOST P 54992– 2012 contain outdated criteria for determining indices and classes of energy efficiency of light sources and luminaires. They are taken from the 1998 EU Directive #98/11/EU “Electric lamps”, in which LED light sources and discharge lamps of high intensity were not included. A new Regulation of the European Union #874/2012/EU on energy labelling of electric lamps and luminaires, in which these light sources are taken into consideration, contains a new technique of determining classes of energy efficiency and new, higher classes are added. The article has carried out a comparison of calculations of the energy efficiency classes in accordance with GOST P 54993 and with Regulation #874/2012/EU, and it is found out that a calculation using GOST P 54993 gives underrated energy efficiency classes. This can lead to interdiction of export for certain light sources and luminaires, can discredit Russian domestic manufacturer light sources and does not correspond to the rules of the World Trade Organization (WTO).

Performance Analysis of TBC-ACO Routing Protocol with Existing Routing Protocols of Wireless Sensor Networks

2017 ◽  
Vol 7 (8) ◽  
pp. 169
Author(s):  
A. Radhika ◽  
D. Haritha
Keyword(s):  
Energy Efficiency ◽  
Wireless Sensor Networks ◽  
Sensor Networks ◽  
Swarm Intelligence ◽  
Routing Protocol ◽  
Routing Protocols ◽  
Energy Efficient ◽  
Sensor Nodes ◽  
Wireless Sensor ◽  
Congestion Aware

Wireless Sensor Networks, have witnessed significant amount of improvement in research across various areas like Routing, Security, Localization, Deployment and above all Energy Efficiency. Congestion is a problem of  importance in resource constrained Wireless Sensor Networks, especially for large networks, where the traffic loads exceed the available capacity of the resources . Sensor nodes are prone to failure and the misbehaviour of these faulty nodes creates further congestion. The resulting effect is a degradation in network performance, additional computation and increased energy consumption, which in turn decreases network lifetime. Hence, the data packet routing algorithm should consider congestion as one of the parameters, in addition to the role of the faulty nodes and not merely energy efficient protocols .Nowadays, the main central point of attraction is the concept of Swarm Intelligence based techniques integration in WSN.  Swarm Intelligence based Computational Swarm Intelligence Techniques have improvised WSN in terms of efficiency, Performance, robustness and scalability. The main objective of this research paper is to propose congestion aware , energy efficient, routing approach that utilizes Ant Colony Optimization, in which faulty nodes are isolated by means of the concept of trust further we compare the performance of various existing routing protocols like AODV, DSDV and DSR routing protocols, ACO Based Routing Protocol  with Trust Based Congestion aware ACO Based Routing in terms of End to End Delay, Packet Delivery Rate, Routing Overhead, Throughput and Energy Efficiency. Simulation based results and data analysis shows that overall TBC-ACO is 150% more efficient in terms of overall performance as compared to other existing routing protocols for Wireless Sensor Networks.

MANUFACTURING OF ENERGY EFFICIENT SOLAR PANELS

2020 ◽  
Author(s):  
Андрей Дмитриевич Бухтеев ◽  
Виктория Буянтуевна Бальжиева ◽  
Анна Романовна Тарасова ◽  
Фидан Гасанова ◽  
Светлана Викторовна Агасиева
Keyword(s):  
Energy Efficiency ◽  
Solar Cells ◽  
Energy Efficient ◽  
Solar Panels

В данном обзоре приведены проблемы при использовании солнечных элементов и существующие решения этих проблем по повышению энергоэффективности фотоэлементов. Также сравнивается КПД этих солнечных элементов и рассматриваются их особенности. Одним из самых эффективных способов стало применение нанотехнологий. This review presents the problems of using solar cells and existing solutions to these problems to improve the energy efficiency of solar cells. The efficiency of these solar cells is also compared and their features are considered. One of the most effective methods was the use of nanotechnology.

Energy efficient biomorphic pulse information coding in electronic neurons for the entrance unit of the neuroprocessor

2019 ◽  
Vol 5 (3) ◽  
pp. 186-212 ◽  
Author(s):  
Alexander D. Pisarev
Keyword(s):  
Neural Networks ◽  
Energy Efficiency ◽  
Energy Efficient ◽  
Information Transfer ◽  
Biological Systems ◽  
Technological Parameters ◽  
Input Unit ◽  
Efficient Operation ◽  
Electric Circuits ◽  
Electronic Neuron

This article studies the implementation of some well-known principles of information work of biological systems in the input unit of the neuroprocessor, including spike coding of information used in models of neural networks of the latest generation.<br> The development of modern neural network IT gives rise to a number of urgent tasks at the junction of several scientific disciplines. One of them is to create a hardware platform&nbsp;— a neuroprocessor for energy-efficient operation of neural networks. Recently, the development of nanotechnology of the main units of the neuroprocessor relies on combined memristor super-large logical and storage matrices. The matrix topology is built on the principle of maximum integration of programmable links between nodes. This article describes a method for implementing biomorphic neural functionality based on programmable links of a highly integrated 3D logic matrix.<br> This paper focuses on the problem of achieving energy efficiency of the hardware used to model neural networks. The main part analyzes the known facts of the principles of information transfer and processing in biological systems from the point of view of their implementation in the input unit of the neuroprocessor. The author deals with the scheme of an electronic neuron implemented based on elements of a 3D logical matrix. A pulsed method of encoding input information is presented, which most realistically reflects the principle of operation of a sensory biological neural system. The model of an electronic neuron for selecting ranges of technological parameters in a real 3D logic matrix scheme is analyzed. The implementation of disjunctively normal forms is shown, using the logic function in the input unit of a neuroprocessor as an example. The results of modeling fragments of electric circuits with memristors of a 3D logical matrix in programming mode are presented.<br> The author concludes that biomorphic pulse coding of standard digital signals allows achieving a high degree of energy efficiency of the logic elements of the neuroprocessor by reducing the number of valve operations. Energy efficiency makes it possible to overcome the thermal limitation of the scalable technology of three-dimensional layout of elements in memristor crossbars.

scholarly journals Determinants of Consumers’ Intentions towards the Purchase of Energy Efficient Appliances in Pakistan: An Extended Model of the Theory of Planned Behavior

2021 ◽  
Vol 13 (2) ◽  
pp. 565
Author(s):  
Muhammad Rizwan Ali ◽  
Muhammad Shafiq ◽  
Murad Andejany
Keyword(s):  
Energy Efficiency ◽  
Theory Of Planned Behavior ◽  
Planned Behavior ◽  
Energy Efficient ◽  
Behavioral Intentions ◽  
Partial Least Square ◽  
Least Square ◽  
Policy Implications ◽  
Extended Model ◽  
Awareness Campaigns

Amplified energy demand due to technologically advanced electrical and electronic appliances has accentuated the importance of energy efficiency to overcome energy shortage and environmental concerns. As adoption of energy efficient appliances depends on perception of the consumers, this study focuses on behavioral exploration of the consumers’ intentions towards the purchase of energy efficient appliances using an extended model of the theory of planned behavior (TPB). The study is based on a survey comprising 289 respondents. Partial least square (PLS) method is used to analyze the data. The results show that the attitude, perceived behavioral control, policy information campaigns, and past-purchase experiences significantly impact behavioral intentions of the consumers, whereas subjective and moral norms are insignificant in shaping behavioral intentions. Based on analyses, policy implications emphasizing (i) strong awareness campaigns, (ii) energy efficiency incentives, and (iii) replacement initiatives are proposed to help policy makers and administrators in achieving required goals of energy efficiency and conservation. The proposed research model and policy initiatives are a blueprint for synergies among policymakers, practitioners, and researchers in understanding and shaping consumers’ behaviors towards the purchase of energy efficient products, particularly, in developing countries.

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