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Ingeaua M.,Polytechnic University of Bucharest | Prisecaru T.,Polytechnic University of Bucharest | Pirna I.,INMA Bucharest | Sorica C.,INMA Bucharest
UPB Scientific Bulletin, Series D: Mechanical Engineering | Year: 2016

Dehydration is an energy intensive process, a very large portion of the energy used in all industrial processes being used by this process. Between 15 to 20% of the total industrial energy consumption worldwide is used for dehydration, therefore optimization of the design and selection of equipment, process control and rational logistics are important factors for improving this process, thus reducing pollution and increasing the economic throughput. In this we paper analyze a portion of the convective dehydration of apples in order to identify opportunities for process optimization through monitoring and control of essential parameters (temperature, relative humidity and air velocity), as well as providing some automatic control algorithms for the dehydration process.

Toncea I.,National Agricultural Research and Development Institute | Necseriu D.,Suisse trail srl | Prisecaru T.,Polytechnic University of Bucharest | Balint L.N.,ICA Research and Development srl | And 2 more authors.
Romanian Biotechnological Letters | Year: 2013

Variability in camelina (Camelina sativa, L. Crantz) seeds and oil composition could be expected between cropping year, sowing time, cultivar and genetic x environment's interactions, as well farming systems. The objectives of the present study were to determine the seeds and oil composition variability due by organic and low input farming systems, cropping year, sowing time and cultivar, as well as, organic seeds, fats and meal (cake) elemental composition and calorific power values of Camelia, first Romanian camelina (Camelina sativa, L. Crantz) cultivar. Between 2004 - 2013 different field experiments with camelina were carried out at NARDI Fundulea, including five years (2009-2013) yield trial in organic farming, and a three year (2008-2010) yield trial in low input farming established that camelina Camelia seeds contain, mainly, 4,25 - 5,24% ash, 11,06 - 15,24% cellulose, 18,87- 21,97% proteins, 30,1 - 49,7% fats, and 25,83 - 28,21 mg/100 g vitamin E, as well as minerals - 0,18% Calcium (Ca), 0,53 % Phosphorus (P), 0,49% Cooper (Cu), 1,39 % Manganese (Mn), 4,47 % Iron (Fe) and 2,56 % Zinc (Zn). In organic yield trial, the best years for Camelia fats(oil) content were 2009 (43,9%) and 2012 (44,2%) and the bad year was 2010 (31,4%). Also, the sowing time effect on fats(oil) content ranged between 29,3 - 46,3% in late autumn and 33,4 - 49,6% in early spring. There appears to be some variation for fats(oil) content among the years and cultivars tested: 31.1 - 45,8% at Camelia, 31,9 - 44,8% at Calena and 30,7 - 43,6% at Lindo. In low input farming system, the fats(oil) content of cultivars studied ranged between 32,7 - 35,9% at Camelia and 29,5 - 33,8% at Lindo. The organic seeds and cold oil of Camelia contained two essential fatty acid types: ω-3 (31,9 - 53,4%) and ω-6 (18,6 - 21,61%), as well nonessential ω-9 (17,4 - 36,6%). The fatty acids in Camelia seeds and cold oil are principally unsaturated (85,3- 89,4%), with only 9,1 - 11,2% being saturated. More than 55% of the fatty acids are polyunsaturated, primarily linoleic (18:2) and a-linolenic (18:3), and 32% are monounsaturated, primarily oleic (18:1), eicosenoic/gadoleic (20:1), and erucic acid (22:1). Camelia a-linolenic fatty acid was higher in late autumn sowing time seeds and oil samples when was compared to that of Camelia seeds and cold oil spring sowing time samples. The average ω-6 to ω-3 ratio in Camelia seeds and cold oil was 1: 1,5 - 2,87 and inverse to the ideal ratio: 3 - 3:1 to 5:1. The Camelia cold oil was susceptible to auto oxidation, thus giving it a shorter shelf life. Also, the fatty acids composition of Camelia seeds and cold oil was not significant different. The calorific power values of the Camelia main commercial products, classified the Camelia seeds besides Anthracite coal, the Camelia meal(cake) besides Bituminous coal, and Camelia cold oil besides Jatropha based biodiesel and fuel oil. © 2013 University of Bucharest.

Fechete Tutunaru L.V.,Technical University of Cluj Napoca | Nagy E.M.,INMA Bucharest | Cota C.-T.,INMA Bucharest
INMATEH - Agricultural Engineering | Year: 2014

The geometry of the cutting edge or of the surface contour is of great importance in minimizing the energy required for the mechanical processing operations. The vast majority of the research conducted so far in the soil processing field focuses on macro geometry of the tools without taking into account the geometry of the cutting edge. This paper presents the results of experimental research regarding the influence of the modification by wear of the constructive parameters of the cutting edge corresponding to the tillage tool on the economic indicators in the working process. Thus was established a mathematical model that highlights the correlation between the processed surface and the linear wear of tools, with which the average area that a tool can process until it reaches a wear limit value, can be determined.

The working capacity of conventional cereal combine harvesters is mainly determined by the working capacity of tangential threshing system. This depends on the technical and functional characteristics of the threshing system itself, the characteristics of the harvested vegetal matter and the characteristics of the feeding threshing system with vegetal matter. The feeding threshing system is made of the feeder house which is composed of a conveyor with chains and slats. The objective of this study is to develop a mathematical model for feeding threshing system with vegetal matter in order to determine the technical and functional characteristics of the conveyor with chains and slats of the feederhouse. Theoretical research in this area did not fully complete the mathematical model.

Bracacescu C.,INMA Bucharest | Sorica C.,INMA Bucharest | Manea D.,INMA Bucharest | Guanxin Y.,Along Agriculture RandD Technology and Management Consulting Co. | Constantin G.A.,Polytechnic University of Bucharest
INMATEH - Agricultural Engineering | Year: 2014

The paper presents the scheme of dynamic calculation of vibrating separator endowed with free vibrating plate and the author contributions concerning the determination of the movement of an intensive cleaner separator endowed with non balanced vibration generating systems. Also there are mentioned the advantages of electrical motovibrators utilisation for driving the vibrating sieves of technical equipment used for cereal cleaning in view of their processing.

The researches whose results are presented in this article aim to theoretically optimize the agricultural machines designed to prepare the germinating bed. For ploughing machinery, an optimization method has been known since 1970-1980. The movement resistance force of ploughing machines was expressed in relation with the forward speed by a formula known since the middle of past century. By means of this formula, the method of optimizing the working regime of ploughing machines was achieved. For the machines designed to preparing the germinating bed, the formula giving the calculation of movement resistance does not depend explicitely on speed, and the constant expressing the soil action in contact with working parts is a global one- a resistance density per machine working width. This constant should be experimentally determined. Our researches have aimed to modify this formula of calculation of movement resistance similarly with that of plowing machines and solve the optimizing problem taking into account the method already used. The researches frame within a scientific unifying current in the field of agricultural mechanics, which purpose is to reduce the diversity of expression by other procedures and generalization. Renouncing to use special formulae lead to large opportunities in conceiving, designing and testing agricultural machines, the agricultural mechanics formulae taking its roots in modern science base.

Popescu C.,Science HOFIGAL Export Import S.A. | Voicea I.,INMA Bucharest | Vladut V.,INMA Bucharest
Romanian Biotechnological Letters | Year: 2015

After harvesting, medicinal and aromatic plants are processed, in order to obtain different products with a wide range of utilizations and this requires complex technological processes ready to be done in a limited period, so the plants active principles are maximally capitalized. For obtaining these active principles (bioactive substances) raw material percolated by extractive solvents. Prior to extraction, breakage operations are needed in order to increase the bioactive substances yield. Following the experimental research achieved by means of suitable technical equipment (breakage machine, percolator, etc), the medicinal plants optimum breakage size have been determined for maximize the extraction efficiency of bioactive substances. The extraction processes and yield optimisation of bioactive substances interest has been determined supported by specific laboratory instruments (TIMATIC, UV-VIS).

The working capacity of conventional cereal harvesting combines is mainly determined by the working capacity of tangential threshing system. This depends on the technical and functional characteristics of the threshing system itself and the biological characteristics of the harvested vegetal mass. Portion of material driven by one bar of threshing cylinder is laminated in to the threshing space and under the action of the friction and centrifugal forces it is produced the combing of material and the seeds separation. The paper presents the kinematic study of threshing process along threshing space and the conditions for optimization of process.

Matache M.G.,INMA Bucharest | Voicu G.,Polytechnic University of Bucharest | Cardei P.,INMA Bucharest | Persu C.,INMA Bucharest
UPB Scientific Bulletin, Series D: Mechanical Engineering | Year: 2016

The paper presents the synthetizing algorithm for an accelerated testing program within laboratory of the MAS65 deep soil loosening machine resistance structure, based on real loads at which it is subjected. We determined the real stress for the MAS65 deep soil loosening machine working organ, through measurements performed in the field. By applying an original counting algorithm on the real signal and synthesizing a blocks testing signal from those cycles, we obtained the accelerated testing program within laboratory.

Cujbescu D.,INMA Bucharest | Vladut V.,INMA Bucharest | Voicu G.,Polytechnic University of Bucharest | Ungureanu N.,Polytechnic University of Bucharest
Engineering for Rural Development | Year: 2016

The paper presents the experimental research conducted on a stand and in the field for a precision seeder, separately or simultaneously with applying liquid herbicides or insecticides. In order to increase the precision degree for the measurements, the compaction wheels were moved sideways by 20 cm, so that they do not cross the seed row. The experiments were performed for three different working speeds, placing one or two corn seeds in each pocket.

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