Improvement of the tube mold to ensure uniform primary cooling of the ingot

2021 ◽  
Vol 77 (3) ◽  
pp. 288-294
Author(s):  
A. S. Smolyakov ◽  
S. I. Shakhov ◽  
B. A. Sivak
Keyword(s):  
Cross Section ◽  
Cooling Water ◽  
Heat Removal ◽  
Quality Parameters ◽  
Uniform Thickness ◽  
Uniform Heat ◽  
Annular Gap ◽  
Cooling Jacket ◽  
The Difference ◽  
Almost All

For centering the cooling jackets of CCM tube molds relative to the tube, bolts twisted into the jacket are used. The adjustment is made manually, as a result the annular gap between the sleeve and the jacket can have a significant deviation from the specified values. The gap function is to cool the structure by passing water. Taking into account that almost all the modern CCMs for casting long, bloom and round billets are equipped with tube molds, creating a mold design in which the gap between the tube and the cooling jacket is formed with a high degree of accuracy, ensuring uniform heat removal from the walls of the tube is an urgent task. This is necessary to ensure a uniform thickness of the shell of the solidifying billet. The conditions were considered for the formation of a uniform shell of a solidifying ingot in a mold and the production of a billet that meets the requirements for its surface and geometric dimensions, the absence of internal and external cracks of thermal origin. It was shown that the violation of the alignment of the cooling jacket and the tube surfaces results in violation of the uniformity of the cooling water flow. The difference in the volume of water flowing in various parts of the gap between the tube and the jacket can reach 40%. When casting billets with diameters of 600 and 550 mm, the difference in heat flows due to misalignment in existing molds can be 30–40% and 25–35% respectively, and with a cross section of 300×400 mm – 13–23%. In order to eliminate these shortcomings, a new design of the tube mold was developed in VNIIMETMASH (Moscow), in which the gap between the sleeve and the cooling jacket is formed with high accuracy, ensuring uniform heat removal from the walls of the tube and obtaining a uniform thickness of the shell of the solidifying ingot. This will ensure that the casted billet meets the requirements for its quality parameters and geometric dimensions. The diagram of the designed mold for the bloom CCM, which produces billets with a cross section of 340×380 mm is presented.

scholarly journals Perasan Daun Pepaya (Carica papaya L.) Sebagai Pengendali Infestasi Argulus Pada Ikan Komet (Carassius auratus auratus) [ Papaya Leaf Juice (Carica papaya L.) For Control Infestation Of Argulus At Comet Fish (Carassius auratus auratus) ]

2019 ◽  
Vol 4 (1) ◽  
pp. 49 ◽  
Author(s):  
Puput Puspitasari, Kismiyati, Laksmi Sulmartiwi
Keyword(s):  
Carassius Auratus ◽  
Carica Papaya ◽  
Fish Farming ◽  
Quality Parameters ◽  
Test Analysis ◽  
Anova Test ◽  
Randomized Design ◽  
The Difference ◽  
Almost All ◽  
Leaf Juice

Abstract Comet fish farming are very popular almost all over Indonesia. Production problems associated with cultivation can not be separated from discussions about the disease that can cause death in fish. One of the parasites known to infect comet fish is Argulus. One alternative to the safe control of ectoparasites is to use papaya leaves. The content of the papaya leaves one of them is an alkaloid carpain. The purpose of this study was to determine which the juice of papaya leaves (Carica papaya L.) can release Argulus that infest comet fish (Carassius auratus auratus) and the concentration of papaya leaf juice is effective as a control Argulus that infest comet fish. The method used is an experimental laboratory with a Completely Randomized Design (CRD) as an experimental design. The treatments used were is the concentration of the difference papaya leaf juice, A (0%), B (20%), C (25%) and D (30%) with five replications. The main parameters of the observed loss of Argulus is attached to the comet fish and behavior of comet fish. Observations include water quality parameters include temperature, pH, and dissolved oxygen. Analysis of data by using ANOVA test (Analysis of Variance),if there is a difference among treatments, followed by Duncan's Multiple range test. The result showed ANOVA test with p <5% indicates that the soaking juice of papaya leaves Argulus infestations affect the comet fish. The best juice of papaya leaves is treatment D (30%) which can move 88% in immersion for 20 minutes.

Numerical Analysis of the Convective Heat Transfer in a Combustor Cooling Jacket

2003 ◽  
Author(s):  
Gustavo Gutierrez ◽  
Tien-Chien Jen ◽  
Tuan-Zhou Yan
Keyword(s):  
Heat Transfer ◽  
Combustion Chamber ◽  
High Efficiency ◽  
Stokes Equations ◽  
Cooling Water ◽  
Heat Removal ◽  
Axial Direction ◽  
Gas Temperature ◽  
Significant Deterioration ◽  
Cooling Jacket

In any combustors and chemical reactos, to achieve high efficiency it is very important to maintain the high gas temperature inside the combustion chamber without significant deterioration of the materials of the walls. Thus, a critical aspect of the design of a combustor or reactor is the development of a method to cool the inner walls of a combustor such that the temperatures on the inner wall are well below the temperature a material can sustain. A typical method to cool a combustor chamber is to use a cooling jacket adjacent to the inner wall of the combustor. In general, the efficiency of this cooling jacket depends on the heat removal capability of the cooling water and the flow channel geometry. It is critically important to control these parameters to enhance the performance of the combustion chamber by decreasing the inner wall temperature below its material limit. This study considers a cylindrical combustor, rotating around its axis. A detailed investigation of the fluid flow and heat transfer processes throughout the cooling jacket is performed. A two-dimensional axial symmetric Navier-Stokes equations and energy equation as a conjugate problem are solved. The flow patterns and temperature distributions of the cooling jacket under the effect of rotation are presented. Also, local friction factor and Nusselt number are calculated along the axial direction.

scholarly journals Apical Extrusion of Debris Produced during Continuous Rotating and Reciprocating Motion

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Giselle Nevares ◽  
Felipe Xavier ◽  
Luciana Gominho ◽  
Flávia Cavalcanti ◽  
Marcely Cassimiro ◽  
...  
Keyword(s):  
Cross Section ◽  
Sodium Hypochlorite ◽  
Reciprocating Motion ◽  
Continuous Motion ◽  
Analytical Balance ◽  
Root Canals ◽  
Apical Extrusion ◽  
Final Weight ◽  
The Difference

This study aimed to analyse and compare apical extrusion of debris in canals instrumented with systems used in reciprocating and continuous motion. Sixty mandibular premolars were randomly divided into 3 groups (n=20): the Reciproc (REC), WaveOne (WO), and HyFlex CM (HYF) groups. One Eppendorf tube per tooth was weighed in advance on an analytical balance. The root canals were instrumented according to the manufacturer’s instructions, and standardised irrigation with 2.5% sodium hypochlorite was performed to a total volume of 9 mL. After instrumentation, the teeth were removed from the Eppendorf tubes and incubated at 37°C for 15 days to evaporate the liquid. The tubes were weighed again, and the difference between the initial and final weight was calculated to determine the weight of the debris. The data were statistically analysed using the Shapiro-Wilk, Wilcoxon, and Mann-Whitney tests (α=5%). All systems resulted in the apical extrusion of debris. Reciproc produced significantly more debris than WaveOne (p<0.05), and both systems produced a greater apical extrusion of debris than HyFlex CM (p<0.001). Cross section and motion influenced the results, despite tip standardization.

Effect of Flaw Dimensions on Ductile Fracture Behavior of Non-Aligned Multiple Flaws in a Plate

2011 ◽  
Author(s):  
Katsumasa Miyazaki ◽  
Kunio Hasegawa ◽  
Koichi Saito
Keyword(s):  
Ductile Fracture ◽  
Flat Plate ◽  
Fracture Behavior ◽  
Maximum Load ◽  
Surface Flaws ◽  
Fracture Tests ◽  
The Difference ◽  
Almost All ◽  
Maximum Minimum

The fitness-for-service codes require the characterization of non-aligned multiple flaws for flaw evaluation, which is performed using a flaw proximity rule. Worldwide, almost all such codes provide their own proximity rule, often with unclear technical bases of the application of proximity rule to ductile or fully plastic fracture. In particular, the effect of flaw dimensions of multiple surface flaws on fully plastic fracture of non-aligned multiple flaws had not been clear. To clarify the effect of the difference of part through-wall and through-wall flaws on the behavior of fully plastic fracture, the fracture tests of flat plate specimens with non-aligned multiple part through-wall flaws were conducted. When the flaw depth a was shallow with 0.4 in ratio of a to thickness t, the maximum load Pmax occurred at penetration of multiple flaws and the effect of vertical distance of non-aligned multiple flaws H on Pmax was not so significant. However, when flaw depth was deep with 0.8 in a/t, Pmax occurred after penetration of flaws and the effect of H on Pmax could be seen clearly. It was judged that the through-wall flaw tests were appropriate for discussion of the effect of H on Pmax and the alignment rule of multiple flaws. In addition, in order to clarify the appropriate length parameter to estimate Pmax of test specimens with dissimilar non-aligned through-wall multiple flaws, the fracture tests of plate specimens were also conducted. The effect of different flaw length on Pmax was discussed with maximum, minimum and averages of dissimilar non-aligned multiple flaw lengths. Experimental results showed that the maximum length lmax would be an appropriate length parameter to estimate Pmax, when the non-aligned multiple through-wall flaws were dissimilar.

A Simulation of a Generalized Thermal Radiating Fin

SIMULATION ◽  
1964 ◽  
Vol 2 (6) ◽  
pp. 19-22
Author(s):  
M.T. Janicke ◽  
L.C. Just
Keyword(s):  
Power Plant ◽  
Cross Section ◽  
Construction Material ◽  
Heat Removal ◽  
Thermodynamic Cycle ◽  
Space Applications ◽  
Maximum Heat ◽  
Electrical Systems ◽  
Extra Weight ◽  
The Relationship

The purpose of this paper is to provide a method for designing radiator fins with maximum heat removal capability per pound of construction material. This problem becomes important when radiators are designed for space applications, since all of the heat from the thermodynamic cycle must be removed by means of radiation. Moreover, space transportation vehicles are seriously limited as to payload, so that weight must be saved in all parts of a power plant. An increase in the output of a space power plant does not change the reactor, turbine, and generator as much as the radiator, with the result that, for megawatt electrical systems, the radiator is the dominant weight contributing component. A radiator could be built of coolant tubes alone, but this increases certain hazards. Meteor punctures can occur, so that the amount of area devoted to coolant tubes should be reduced as much as pos sible. Fins attached between the tubes can perform this function by extending the heat radiating surface. The extra weight of the fins is partly compensated for by a reduction in tubes and coolant. Extra savings can occur if the weight of the fin is minimized; optimum thickness, length, and cross section must be found. This paper studies the relationship between fin cross- section and radiating power.

United Front: Partisans of the Leningrad Region and their connections with the Central Asian Soviet Republics

2021 ◽  
Vol 2021 (02) ◽  
pp. 214-225
Author(s):  
Sergey Kulik ◽  
Аnatoliy Kashevarov ◽  
Zamira Ishankhodjaeva
Keyword(s):  
World War Ii ◽  
Weather Conditions ◽  
Leningrad Region ◽  
World War ◽  
North West ◽  
The North ◽  
Occupied Territory ◽  
Central Asian ◽  
The Difference ◽  
Almost All

During World War II, representatives of almost all the Soviet Republics fought in partisan detachments in the occupied territory of the Leningrad Region. Among them were many representatives of the Central Asian republics: Kazakhstan, Kyrgyzstan and Uzbekistan. Many Leningrad citizens, including relatives of partisans, had been evacuated to Central Asia by that time. However, representatives of Asian workers’ collectives came to meet with the partisans. The huge distance, the difference in cultures and even completely different weather conditions did not become an obstacle to those patriots-Turkestanis who joined the resistance forces in the North-West of Russia.

Theoretical study on photoemission of double-layer AlxGa1−xAs/GaAs nanocone array photocathode

2021 ◽  
Author(s):  
Yan Sun ◽  
Lei Liu ◽  
Zhisheng Lv ◽  
Xingyue Zhangyang ◽  
Feifei Lu ◽  
...  
Keyword(s):  
Cross Section ◽  
Light Trapping ◽  
Spectral Response ◽  
Circular Cross Section ◽  
Geometrical Parameters ◽  
Internal Electric Field ◽  
Surface Emission ◽  
The Difference ◽  
Section Structure ◽  
Light Capture

In the design of photocathode, the internal electric field could be formed due to the graded Al compositional [Formula: see text] nanostructure, which can improve the top surface emission probability of carriers. In this paper, [Formula: see text] nanostructure array photocathode composed of two sub-layers is presented. Based on the finite element method, the influence of graded geometrical parameters on their optoelectronic characteristics is investigated. The results show that when the thickness of the sublayer is equal, the difference of the Al composition between the two sublayers of nanostructure is larger, the sub-layers are less, and the quantum efficiency is higher. The light capture ability of the photocathode can be enhanced by increasing the thickness and the array spacing of the first sublayer. Compared with the hexagonal cross-section structure, the light trapping effect and spectral response of the circular cross-section structure are better.

Monitoring and Assessment of Water Quality in Fuchunjiang and Hangzhou Reaches of Qiantangjiang Estuarine Zone

2013 ◽  
Vol 316-317 ◽  
pp. 711-714
Author(s):  
Zhi Yong Dong ◽  
Yong Gu ◽  
Shuo Shuo Wang ◽  
Ying Biao Shi ◽  
Ruo Hua Li ◽  
...  
Keyword(s):  
Water Quality ◽  
Cross Section ◽  
Cross Sections ◽  
Ph Value ◽  
Flood Plain ◽  
Quality Parameters ◽  
Main Channel ◽  
Water Quality Parameters ◽  
Vertical Line ◽  
Estuarine Zone

This paper presents monitoring investigation of water quality parameters in Fuchunjiang and Hangzhou reaches of Qiantang estuarine zone by YSI 6600 V2-4-M multi-parameter water quality sonde. The 7 monitoring cross-sections were streamwise placed, and the 2 vertical lines respectively located in flood plain and main channel at each cross-section. Surface, intermediate and bed layers were chosen at each vertical line in main channel, and surface and bed layers at each vertical line in flood plain. At each vertical line, the main water quality parameters such as dissolved oxygen, salinity, turbidity, pH value, electrical conductivity and oxidation reduction potential were monitored, variation of these parameters along longitudinal and vertical directions analyzed, and water quality conditions at each monitoring cross-section assessed.

scholarly journals Budidaya ikan mas (Cyprinus carpio) sistem akuaponik dengan padat penebaran berbeda

2019 ◽  
Vol 7 (2) ◽  
Author(s):  
Darwis Darwis ◽  
Joppy D. Mudeng ◽  
Sammy N.J. Londong
Keyword(s):  
Water Quality ◽  
Cyprinus Carpio ◽  
Stocking Density ◽  
Quality Parameters ◽  
Water Volume ◽  
Daily Growth ◽  
Growth And Survival ◽  
Experimental Fish ◽  
The Difference

This research aimed to determine the stocking density that support the best growth and survival rate of carp cultivated in aquaponic systems, and to study the water quality of carp culture with different stocking densities in aquaponic systems. The study used 12 aquaria measuring 40x40x40 cm each (water volume of 50 liters). The experimental fish are carp (Cyprinus carpio) weighing in average of 3.5 g/individual.  The fish were cultivated with different stocking densities as treatment, including A = 4; B = 7; C = 10 and D = 13 individuals/aquarium.  The fish were fed with pellet at 5%/body weight/day with a feeding frequency of two times a day. The study was conducted for 4 weeks. Data consisting of daily growth, survival and water quality parameters (temperature, pH, dissolved oxygen, ammonia, nitrite and nitrate) were measured once a week. The data obtained were analyzed by ANOVA. The results of the study showed that the difference in stocking density had no significant effect on the growth and survival of carp.  Water quality was in a reasonable range to support the growth and survival of carp cultivated with aquaponic systems.Keywords: cultivation, carp, aquaponics, stocking density, growth

Sign in / Sign up

Export Citation Format

Share Document