Dynamic synchronization of the unbalanced rotors for the excitation of longitudinal traveling waves

The problem about the synchronization of the unbalanced rotors for the excitation of the longitudinal traveling waves in the elastic system of a bar type is examined. The steady-state regimes of motion are investigated, the conditions of their existence and stability are obtaine

Dynamic orientation of systems for excitation of transverse and longitudinal waves

A theoretical and numerical analysis of dynamic systems for excitation of longitudinal and transverse waves with a self-direction is carried out. Formulas for definition of excitation frequency and a difference of phases depending on system parameters are obtained. Conditions for existence and stability of the steady-state motion regimes are define

Evaluation of potential biogas production in Sicily

The aim of the present work is to predict the Sicilian potential biogas production, using the below unmarketable raw materials. The statistical data about OFMSW, the number of animals bred on medium and large farms and the amounts of by-products of food processing industries have been evaluated, in order to compute the potential biogas production and energy in the nine provinces of Sicily. In Sicily (Italy) 5.05 million inhabitants (2012), living in nine provinces, could produce 0.8 million tons of the Organic Fraction of Municipal Solid Waste (OFMSW) per year. At present only 0.07 million tons (3.17 % ca. of MSW) are actually treated (2010). This fraction would be one of the raw materials inside the mixture usable for biogas production, in a region where no co-digestion plant is nowadays available. About 1.7 million tons of animal manure might be used for biogas production on medium and big farms. From food industry about 350 thousand tons of organic by-products might be collected. The total potential of biogas production in Sicily is 156.9 millions of m3 that is equal to 941.4 GWh of energy per year. Contribution from animal manure is 402 GWh, from OFMSW - 303 GWh and food industry - 236 GWh. The best possibilities for biogas production are in the provinces of Palermo, Messina and Ragusa, having a potential energy production of 177 GWh, 133.2 GWh and 132 GWh, respectively

Investigation of Oil - Water Ultrasound Emulsifier

Diesel fuel and water emulsifier designed for diesel fuel contaminated with water mixing to improve fuel combustion properties, it could also be used as mixing device for water and diesel fuel mixture. Examined literature describing the oil and water mixture emulsifiers. Analyzed the experiments related to diesel fuel and water emulsion combustion and distribution of its water volume. It has been developed and described principle emulsifier scheme. Calculated and modeled piezoelectric ultrasonic vibration actuator, which causes cavitations in mixing chamber. Ultrasonic vibration actuator is designed for the cavitation emulsion processing. Comparing experimental data with calculations obtained less than 10% deviation from the theoretical resonance frequency values. Performed experimental testing of ultrasonic vibration actuator to determine its resonance values. It also performed test of the distribution of water drops in diesel fuel using a microscope. Diesel fuel combustion effluents is one of the major problems stopping air pollution, especially in more populated areas

Optimization of the Parameters of Solar Water Heating System

In order to investigate the possibility to increase the efficiency of a flat-plate solar collector the mathematical model of the collector has been worked out. By solving the Laplace heat transfer equation at the boundary conditions accordingly to the construction of the collector, the obtained solution gives possibility to simulate on a computer the construction of the collector in dependence on physical, thermal and economic values of materials used for the construction. The computed results by theoretical formulas with experimental results obtained on special laboratory equipment have been compared and good concurrence acquired

Mechanism of generation of the flexural vibrations in an ultrasonic waveguide

This article deals with the problem of transfer of ultrasonic vibrations on flexible hub-waveguide system and is a continuation of research in this field [1-3]. The main field of application of flexible hub-waveguides-minimally invasive surgery for treatment of vascular diseases, where they are used to restore patency of blood vessels by destroying blood clots and tromboèmbolov. Thanks to the possibility of elastic deformation of flexible hub-waveguides, they can be delivered through a catheter system to the most remote places of the blood vessels, producing ultrasonic processing of affected sites with minimal surgical intervention. It should be borne in mind that during the work of the PA system can change its own hub-frequency waveguides and frequency generator, and this can lead to beating frequencies, formation of flexural vibrations of a working part, etc. This article therefore tasked to define the conditions of formation of low-frequency oscillations of a bend when passing ultrasonic vibrations of flexible waveguide system

Continuous quantum measurement of a Bose-Einstein condensate: a stochastic Gross-Pitaevskii equation

We analyze the dynamics of a Bose-Einstein condensate undergoing a continuous dispersive imaging by using a Lindblad operator formalism. Continuous strong measurements drive the condensate out of the coherent state description assumed within the Gross-Pitaevskii mean-field approach. Continuous weak measurements allow instead to replace, for timescales short enough, the exact problem with its mean-field approximation through a stochastic analogue of the Gross-Pitaevskii equation. The latter is used to show the unwinding of a dark soliton undergoing a continuous imaging.Comment: 13 pages, 10 figure

Sicilian potential biogas production

This study is aimed at predicting the Sicilian potential biogas production, using the Organic Fraction of Municipal Solid Waste (OFMSW), animal manure and food industry by-products, in a region where only one biogas plant using MSW and one co-digestion plant are nowadays available. The statistical data about OFMSW, the number of animals bred in medium and large farms and the amounts of by-products of food processing industries were evaluated, in order to compute the Sicilian potential biogas and energy production. The OFMSW produced in Sicily, that is 0.8 million tons ca. per year (37% of MSW), could be used in a bio-reactor, together with other raw materials, for Anaerobic Digestion (AD) process, producing biogas and \u201cdigestate\u201d. Moreover, 3.03 million tons ca. of manure, collected in medium and large animal husbandry farms (where cows, pigs and poultry are bred), and 350 thousand tons ca. of by-products, collected in food processing industries (pomace from olive oil mills and grape marc from wineries), might be used for AD process. The Sicilian potential biogas production from the AD of the above raw materials is 170.2 millions of m3, that is equal to 1023.4 GWh of energy per year, of which 484 GWh from animal manure, 303 GWh from OFMSW and 236.4 GWh from food industry by-products. The highest biogas production is in the province of Palermo (35.6 millions of m3), Ragusa (30.8 millions of m3) and Catania (22.8 millions of m3), having a potential energy production of 213.8, 185 and 137 GWh, respectively

Dynamic synchronization of the unbalanced rotors for the excitation of longitudinal traveling waves

The problem about the synchronization of the unbalanced rotors for the excitation of the longitudinal traveling waves in the elastic system of a bar type is examined. The steady-state regimes of motion are investigated, the conditions of their existence and stability are obtaine

Dynamic orientation of systems for excitation of transverse and longitudinal waves

A theoretical and numerical analysis of dynamic systems for excitation of longitudinal and transverse waves with a self-direction is carried out. Formulas for definition of excitation frequency and a difference of phases depending on system parameters are obtained. Conditions for existence and stability of the steady-state motion regimes are define