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[en] The article considers experimental studies of the hydrodynamic characteristics of the active section of the self-draining solar loop of a heating system. This element is designed as a flow constrictor referred to as Ventury tube, with a high degree of flow constriction of 2–5 in the region with strong viscous resistance. The experimental data are processed in a criteria form, the general type of which is obtained by dimensional technique and compared with data from other authors. The obtained criteria dependences can be used to calculate the hydrodynamic characteristics of the active section of the self-draining solar loop of a heating system.
[en] The stability of α-, (β+γ)- and δ-tocopherols present in rice bran oil at different heating temperatures has been evaluated. For this purpose, samples of rice bran oil from chemical and physical refining processes in Brazilian industries were studied. The oils were submitted to cabinet drying without air circulation in the absence of light at 100 ºC, 140 ºC and 180 ºC. The samples were taken before heating and after 48, 144, 240, 336, 432, 576, 768, 1008 and 1368h of heating. The analyses of tocopherols were made by high performance liquid chromatography, with a fluorescence detector. It was determined that α-tocopherol was the compound with the fastest degradation rate at the three heating temperatures. The highest degradation rate of tocopherols in both oils occurred at 180 ºC. Among the tocopherols studied, α tocopherol presented the lowest stability, followed by (β+γ)- and δ-tocopherols.
[es]La estabilidad de los tocoferoles α-, (β + γ) - y δ presentes en los aceites de salvado de arroz a diferentes temperaturas de calentamiento fueron evaluadas. Para ello, se utilizaron muestras de aceite de salvado de arroz proveniente de los procesos de refinación química y física de industrias brasileñas. Los aceites fueron sometidos a 100 ºC, 140 ºC y 180 ºC, en cabinas de secado sin circulación de aire, bajo ausencia de luz. Las muestras fueron tomadas antes de la calefacción y después de 48, 144, 240, 336, 432, 576, 768, 1008 y 1368 h de calentamiento. El análisis de tocoferoles fue realizado por cromatografía líquida de alta eficacia, con detector de fluorescencia. Se observó que el α-tocoferol fue el compuesto con degradación más rápida en las tres temperaturas de calentamiento. La mayor tasa de degradación de los tocoferoles, en ambos aceites, ocurrió a la temperatura de 180 ºC. Entre los tocoferoles analizados, α-tocoferol presentó menor estabilidad, seguido por los (β + γ) - y δ-tocoferoles
[en] In this paper, experimental investigation of the molten metal jet's colliding and spreading behaviors on the flat steel surface covered with water layer was carried out. High-frequency induction heating system was utilized to produce the molten metal sample and it was released to the wet surface from a fixed elevation. As the molten metal collides against the surface, it rapidly goes through solidification while spreading on the wet surface. High-speed thermo-camera was utilized to measure the molten metal's surface temperature during the spreading transient. Once the molten metal completely solidifies, molten metal's spread area and thickness were measured. From the obtained database, a dimensional analysis was conducted to investigate the key parameters responsible for the molten metal spreading on the wet surface. Based on the key non-dimensional parameters identified in the current analysis, the new empirical correlation was proposed. Its predictive capability was found to be 18.9% in mean absolute relative deviation.
[en] Cyclotron CS-30 is a charged particle accelerator owned by BATAN. One of the requirements for the operation is moisture condition (humidity) in the Cyclotron Cave which should be below 55 %. Damage of the heating system (duct heater) makes the humidity rises above the limit value. To overcome these problems modifications have been made to the duct heater control with the aim of reviving the heating system and maintaining the reliability of the heating system so that stability of humidity can be achieved. The methodology used here is by to utilizing the incoming air flow of the VAC system as an indication to control the operation of the heating system. Therefore an air flow-based control unit has been built that can operate the heating system so that the stability of the humidity in the Cyclotron Cave can be achieved. (author)
[en] The presence of flavored olive oils (FOO) on the market represents an answer to an increasing consumer demand for novel and healthy food. This work aims to compare the sensory acceptability and the thermal stability of FOO prepared by mixing different flavors (lemon, onion, garlic, paprika) to an extra virgin olive oil (EVOO) also used as the control sample. 96 Tunisian citizens were involved in a consumer test and the lemon flavored oil was the most liked whereas the least liked was the oil with onion. Samples were subjected to different heat treatments (60 °C, 100 °C, 200 °C for 1, 2, 4, 8 hours) and the flavor addition did not influence the EVOO stability when samples were heated at 60 °C, whereas at 200 °C the FOO with onion and garlic showed higher oxidative stability. The thermo-oxidation process at 60 °C and at 100 °C of the FOOs was not detrimental for the volatile compound markers but the effect was noticeable for all these markers at 200 °C.
[es]La presencia de aceites de oliva con sabor (FOO) en el mercado representa una respuesta a la demanda cada vez mayor de los consumidores de alimentos novedosos y saludables. Este trabajo tiene como objetivo comparar la aceptabilidad sensorial y la estabilidad térmica de FOO preparado mediante la mezcla de diferentes sabores (limón, cebolla, ajo, pimentón) a un aceite de oliva virgen extra (AOVE), utilizado como muestra de control. 96 ciudadanos tunecinos participaron en una prueba de consumo: el aceite con sabor a limón fue el que más gustó, mientras que el que menos gustó fue el de la cebolla. Las muestras se sometieron a diferentes tratamientos térmicos (60 °C, 100 °C y 200 °C durante 1, 2, 4, 8 horas). La adición de saborizantes no influyó en la estabilidad del AOVE cuando las muestras se calentaron a 60 ° C mientras que a 200 °C el FOO con cebolla y ajo mostraron una mayor estabilidad oxidativa. El proceso de termooxidación a 60 °C y a 100 °C de los FOO no fue perjudicial para el marcador de compuestos volátiles, en oposición al efecto a 200 °C que resultó notable para todos estos marcadores.
[en] The technique for calculating the start and end times and the direct sunlight illumination period is described. The cumulative solar radiation (SR) falling on the front surface of translucent enclosures (TE) of heated premise (HP) is found. The final design results are based on processing 4-year generalized data from the Parkent weather station.
[en] Highlights: • Test of three ESPs at old residential wood combustion systems over two heating seasons. • Collection of a huge set of plant operation data during a continuous 2 year monitoring. • Comprehensive evaluation of the plant monitoring data to analyse the ESP operation. • Data from two dedicated emission measurement campaigns per heating season and ESP. • Comprehensive data on ESP operation, availability and emission reduction efficiency. - Abstract: To assess the applicability of electrostatic precipitators (ESP) for particulate matter (PM) emission reduction in old residential wood heating appliances comprehensive field tests with accompanying ESP operation monitoring and dedicated emission measurement campaigns have been performed in the region of Graz (AT). Three OekoTube ESPs were thereby tested during the heating seasons 2014/2015 and 2015/2016 at different sites with rather old respectively high-PM-emission wood burning devices. Before installing the ESPs at the field testing sites they were checked in the lab regarding functionality and precipitation efficiency. The evaluation of the plant monitoring data collected during the field tests revealed high seasonal ESP availabilities between 80.2% and 97.7%. Dedicated test runs with emission measurements at the different testing sites showed high precipitation efficiencies which were well comparable with those gained during preceding lab-tests. Based on these results it can be concluded, that ESP models like the OekoTube are suitable as retrofit units in old appliances and have due to their high availability and particle precipitation efficiency the potential to contribute to a significant reduction of particulate matter emissions from old residential wood burning systems.
[en] Full text: In order to achieve thermonuclear-relevant plasma parameters in ITER, the auxiliary heating systems have to provide 50 MW, out of which 33 MW by two neutral beam injectors (NBI), each designed to operate at 1 MV, 40 A for one hour. The unprecedented parameters and the complexity of the NBI systems have led to recognize the need of a dedicated test facility to carry out an international R&D programme aimed at realizing, testing and optimizing the prototype of the NBI and to assist ITER during its operation. This facility is under construction in Padova Italy at Consorzio RFX premises and hosts two experiments: MITICA, a 1 MeV full-size prototype of the ITER NBI, and SPIDER, a full-size prototype of the ion source for ITER NBI. The realization of the two experiments is carried out with the main contribution of the European Union, channelled through the Joint Undertaking for ITER (F4E), the ITER Organization and Consorzio RFX, with the Japanese and the Indian ITER Domestic Agencies (JADA and INDA) and European laboratories, such as IPP-Garching among others. The realization of MITICA and SPIDER progresses in parallel; presently, the installation phase of SPIDER is proceeding in good agreement with the general plan. This paper mainly focusses on the integration issues and complementary research toward the SPIDER first operation, expected for next year. This is a very crucial phase, evolving along three main parallel paths: integration and testing of SPIDER components, completion and implementation of diagnostics and preparation of operation and research plan. The most interesting aspects of the wide set of activities, studies and further developments, all concurrent to determine the success of the SPIDER start of operation and exploitation will be described and discussed. (author)
[en] The article presents the results of experimental and numerical tests of a surface heating flow control system consisting of a distribution rail along with the fixed valve. The components were measured, their solid models were prepared and used to make a flow model. In a flow model geometry the measurements of the test stand elements were considered in order to compare the results. (paper)
[en] The Prototype-Material Plasma Exposure eXperiment (Proto-MPEX) linear plasma device is a test bed for exploring and developing plasma source concepts to be employed in the future steady-state linear device Material Plasma Exposure eXperiment (MPEX) that will study plasma-material interactions for the nuclear fusion program. The concept foresees using a helicon plasma source supplemented with electron and ion heating systems to reach necessary plasma conditions. Here in this paper, we discuss ion temperature measurements obtained from Doppler broadening of spectral lines from argon ion test particles. Plasmas produced with helicon heating alone have average ion temperatures downstream of the Helicon antenna in the range of 3 ± 1 eV; ion temperature increases to 10 ± 3 eV are observed with the addition of ion cyclotron heating (ICH). The temperatures are higher at the edge than the center of the plasma either with or without ICH. This type of profile is observed with electrons as well. Finally, a one-dimensional RF antenna model is used to show where heating of the plasma is expected.