STUDY OF EFFICIENCY OF DRUM DRYERS OF METALLURGICAL PRODUCTIONS USING PERFORATED PIPES WITH LOCALIZATION OF HEAT FLOWS

2020 ◽  
pp. 31-40
Author(s):  
V. N. Kokorin ◽  
P. V. Yemeniev ◽  
O. G. Duyun ◽  
O. G. Krupennikov
Keyword(s):  
Risk Factors ◽  
Heat Fluxes ◽  
Heat Flows ◽  
Processed Material ◽  
Temperature Heat ◽  
Dispersed Material ◽  
Horizontal Drum ◽  
Perforated Pipe ◽  
Perforated Tube ◽  
Boiling Zone

The article presents the design of a drum furnace, providing for the provision of differentiated heat flows through the use of an internal perforated pipe. The design of the presented horizontal drum dryer with a perforated tube having openings is designed to eliminate such technological risk factors as the ignition of the oil component of the processed material, and the metal dispersed material itself having pyrophoric properties. As a result of the numerical simulation using the LS–DYNA program, the temperature and heat fluxes in the quasi-boiling zone of the drained oil-containing dispersed material were determined. The calculations made it possible to establish the dependence of the temperature in the quasi-boiling zone on the number of holes of the perforated pipe. Analysis of the obtained graphs allows us to conclude that the gradient of temperature (heat) flows in fixed sections of the furnace of the quasi-boiling zone.

scholarly journals Transformation Thermodynamics with Arbitrarily Shaped Non-Conformal Objects and Coatings

2018 ◽  
Vol 186 ◽  
pp. 01007
Author(s):  
Qingxiang Ji ◽  
Guodong Fang ◽  
Jun Liang
Keyword(s):  
Thermal Protection ◽  
Small Region ◽  
Heat Fluxes ◽  
Temperature Fields ◽  
Heat Flows ◽  
Thermal Protection Systems ◽  
Thermal Fields ◽  
Design Flexibility ◽  
Protection Systems ◽  
Concentrate Heat

In this paper we apply transformation optics theory to thermodynamics and design thermal cloaks and concentrators with arbitrarily shaped non-conformal objects and coatings. Expressions of the required material parameters are derived analytically and then validated by numerical simulations. We apply this method to design a thermal cloak which can guide the heat flow around the inner domain without perturbation to external thermal fields. In this way, the object inside the inner domain is protected from the invasion of external heat fluxes. In contrast, a concentrator is designed to concentrate heat flows into a small region without disturbing outside temperature fields, which can considerably enhance the heat density in the designed domain. The proposed method extends the design flexibility in manipulating heat flux and will find wide applications in thermal protection systems, solar cells and so on.

scholarly journals Characterization of stovetop cooking oil fires

2018 ◽  
Vol 36 (3) ◽  
pp. 224-239 ◽  
Author(s):  
Anthony Hamins ◽  
Sung Chan Kim ◽  
Daniel Madrzykowski
Keyword(s):  
Heat Release ◽  
Room Temperature ◽  
Corn Oil ◽  
Fire Suppression ◽  
Heat Fluxes ◽  
Release Rates ◽  
Free Standing ◽  
Cooking Oil ◽  
Temperature Heat

A series of cooking fire experiments were conducted by the National Institute of Standards and Technology to examine the hazard associated with cooking oil fires. First, a series of 12 experiments were conducted on a free-standing stove situated in the open. The experiments were based on scenarios outlined in the draft UL 300A standard for fire suppression apparatus. Both the gas and electric ranges were tested. The amount of oil and types of cooking pans were varied in the experiments. Oil was heated on a cooktop burner until autoignition took place. Measurements of oil and pan temperatures, heat release rates, and heat fluxes were made to characterize the hazard of the ensuing fires. Next, two experiments were conducted using a full-scale residential kitchen arrangement to examine the hazard associated with the free-burning oil fires situated within a compartment equipped with commercial furnishings, fiberboard cabinets, and countertops. The dimensions of the test room were 3.6 m × 3.4 m × 2.4 m. Corn oil was heated on a cooktop burner until autoignition took place. Measurements of room temperature, heat fluxes, and heat release rates showed that even small cooktop fires spread and grew ultra-fast within the kitchen compartment.

Application of a Discrete Transfer Matrix Method in Analysis of Acoustic Attenuation Performance of Complex Perforated Pipe Mufflers

2013 ◽  
Vol 419 ◽  
pp. 140-144
Author(s):  
Huo Rui ◽  
Meng Bei ◽  
Zhang Lei
Keyword(s):  
Transfer Matrix ◽  
Transmission Loss ◽  
Influential Factors ◽  
Calculation Formula ◽  
Acoustic Attenuation ◽  
Noise Elimination ◽  
Discrete Method ◽  
Factors Analysis ◽  
Perforated Pipe ◽  
Perforated Tube

The article is about an application of a discrete method for analyzing acoustic attenuation performance of perforated tube mufflers. Acoustic transfer matrix of a tiny perforated tube section which contains one single hole is deduced based on basic hydromechanics equations. Then the work is developed into a general formula for resolving sound transmission loss of one perforated silencer unit consisting of multiple parallel perforated pipes. Result of the calculation formula is compared with that of acoustic finite element method. One more example is presented on influential factors analysis for noise elimination performance of a practical complex perforation muffler.

scholarly journals Calculations of Heat Transfer in Furnaces of Steam Boilers under Laws of Radiation of Gas Volumes and Development of Innovative Designs of Furnaces

2020 ◽  
pp. 9-18
Author(s):  
Anatoliy Nikolaevich Makarov
Keyword(s):  
Heat Transfer ◽  
Thermal Radiation ◽  
20Th Century ◽  
Local Information ◽  
Heat Fluxes ◽  
Accurate Data ◽  
Heat Flows ◽  
Methods Of Calculation ◽  
Foreign Countries ◽  
Steam Boilers

The analysis of heat transfer in furnaces of steam boilers is carried out. Throughout the 20th century, due to the lack of precise methods of calculation in Russia and foreign countries, there was incomplete local information about the scope of heat fluxes in furnaces. After the discovery by the author of the laws of thermal radiation of gas volumes, it became possible to obtain accurate data on the distribution of heat flows along with the height and perimeter of the screen surfaces of fire chambers (furnaces). The executed calculations showed essential no uniformity of distribution of heat fluxes, vaporization, and in-pipe deposits on height and perimeter of screen surfaces of fire chambers. Proposed are innovative furnaces, in which the distribution of heat fluxes, vaporization, in-pipe deposits on the screen surfaces are leveled.

Experimental Methodology to Characterize Mechanical Losses in Small Turbochargers

2010 ◽  
Author(s):  
Francisco Payri ◽  
Jose R. Serrano ◽  
Pablo Olmeda ◽  
Arlington Paez ◽  
Fabrice Vidal
Keyword(s):  
Heat Transfer ◽  
Operating Temperature ◽  
Mechanical Efficiency ◽  
Experimental Methodology ◽  
Current Work ◽  
Lubricating Oil ◽  
Heat Flows ◽  
Friction Power ◽  
Wide Range ◽  
Temperature Heat

Turbocharging and turbocharger phenomena have been studied by many authors covering a wide range of subjects. One of these subjects, and objective of this work, is mechanical losses due to friction. Current work presents a methodology to characterize mechanical losses in small size turbochargers. Such methodology is based on low and constant operating temperature values for the turbine, lubricating oil, and compressor. In this way, a quasi-adiabatic operation of the turbocharger is achieved which allows separating friction power from heat transfer. The experiments performed have covered variations in turbocharger speed, lubricating oil pressure and temperature. Heat flows between turbine and compressor has been maintained as reduced as possible by means of the experiment conditions. The results obtained show satisfactory correlation between mechanical efficiency of the studied turbocharger and non-dimensional magnitudes.

scholarly journals Reaction Sequences in Flash Smelting and Converting Furnaces: An In-depth View

2021 ◽  
Author(s):  
Pekka Taskinen ◽  
Ari Jokilaakso
Keyword(s):  
Nickel Sulfide ◽  
Scientific Literature ◽  
Heat Fluxes ◽  
Flash Smelting ◽  
Flow Sheet ◽  
Acid Plant ◽  
Heat Flows ◽  
Unit Operations ◽  
Flash Converting ◽  
Reaction Zones

Abstract Flash smelting and flash converting are mature technologies in copper and nickel sulfide smelting. The sensitivity of operation concerning the furnace design is evident. It is obvious that when two unit operations are carried out in separate spaces in the same furnace, skills related to maintenance of suspension oxidation of fine minerals, fluxing, fluid as well as heat flows and the overall energy balance are required. Despite these fundamental features, the flow-sheet wide understanding of linking the suspension oxidation of sulfides with the subsequent smelting processes in the furnace as well as the chemistry of its off-gas train is largely absent in the scientific literature. This review gives a detailed outlook on the microscale phenomena in flash smelting and flash converting furnaces accumulated during the last decades. It connects their vital features and chemistries with the reaction tendencies and heat fluxes in the different parts and reaction zones of the furnace as well as in the off-gas train from the smelter to the acid plant. Graphic Abstract

Active Heating/Cooling Requirements for Divers in Water at Varying Temperatures

2007 ◽  
Author(s):  
Erik R. Bardy ◽  
Joseph C. Mollendorf ◽  
David R. Pendergast
Keyword(s):  
Heat Flux ◽  
Human Subject ◽  
Heat Fluxes ◽  
Body Temperatures ◽  
Thermal Exchange ◽  
Thermal Limits ◽  
Body Regions ◽  
Temperature Heat ◽  
The Subject ◽  
Skin Temperatures

The active heating/cooling requirements to thermally sustain a human subject submerged in 10, 20, 30 and 40 °C water was measured using a system that circulated water through a zoned tubesuit garment. Water at 30 °C was circulated through the garment at a flow rate of about 0.5 L/min to each of six body regions and the outlet temperatures were measured. In addition, skin and core temperature, heat flux, and oxygen consumption was measured. The subject wore either a 6.5 mm or a 3 mm foam neoprene wetsuit. Body temperatures and heat fluxes reached steady state after 30–90 minutes and the immersions lasted 2–4 hours and core and skin temperatures remained within set thermal limits. In both wetsuits there was a linear correlation between the thermal exchange of the tubesuit and water temperature. While in the 6.5 mm wetsuit −214 to 242 W of heating (−) or cooling (+) was necessary in 10 to 40 °C water, respectively. While wearing the 3 mm wetsuit −462 to 342 W was necessary in 10 to 40 °C water, respectively. It was therefore concluded that a subject can be kept in thermal balance and comfort in 10–40 °C water with active heating/cooling.

scholarly journals ENERGY SAVING OF MODULAR BUILDINGS WITH THE HELP OF BIOGAS TECHNOLOGIES

2021 ◽  
Vol 2021 (2) ◽  
pp. 82-94
Author(s):  
Vasyl Zhelykh ◽  
◽  
Yurij Furdas ◽  
Stepan Shapoval ◽  
Olena Savchenko ◽  
...  
Keyword(s):  
Anaerobic Fermentation ◽  
Biogas Production ◽  
Raw Materials ◽  
Heat Fluxes ◽  
Raw Material ◽  
Methane Formation ◽  
Land Resources ◽  
Heat Flows ◽  
Main Factors ◽  
Fallen Leaves

Ukraine has significant land resources for agriculture and is able to provide its population not only with food but also with raw materials for bioenergy. The article presents a graph of heat capacities and the distribution of heat flows in a bioreactor. The dependences for determining the heat fluxes of flat and cylindrical surfaces are presented. The article outlines the present state of utilization of fallen leaves of trees. The method of utilization by anaerobic fermentation is proposed. The design of bioreactors and the main factors influencing the methane formation process are considered. The methodology for calculating the biogas production process is presented. The productivity of the bioreactor has been determined, depending on the temperature of the raw material and the time of hydraulic resistance

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