Furnace Temperature Optimal Setting of the Dispersal Reversing Furnace

2014 ◽  
Vol 692 ◽  
pp. 411-415
Author(s):  
Hui Cheng Jing ◽  
Xiao Qing Liu
Keyword(s):  
Optimal Allocation ◽  
Longitudinal Direction ◽  
Mechanism Analysis ◽  
Furnace Temperature ◽  
Cross Sectional ◽  
Discrete State ◽  
Object Use ◽  
Optimal Setting ◽  
Steady State Heat ◽  
Tolerance Method

This paper is based on the heating furnace of Zhao-feng Steel Works, Chengde, and according to the characteristics of the research object, use the method that the mechanism analysis combining with the discrete state space method to build billet one-dimensional mathematical model of steady-state heat conduction. Setting up the objective function of the minimum fuel consumption, taking billet baked surface temperature, the maximum cross-sectional temperature, heating rate and furnace temperature settings as constraints obtained and using a variable tolerance method to obtain the furnace temperature settings for each segment. When the output is constant, the optimal allocation of heat load along the longitudinal direction can be obtained by this model, which has a good guidance for the actual production.

scholarly journals Scrotal reconstruction with superomedial fasciocutaneous thigh flap

2018 ◽  
Vol 45 (1) ◽  
Author(s):  
DANIEL FRANCISCO MELLO ◽  
AMERICO HELENE JÚNIOR
Keyword(s):  
Surgical Treatment ◽  
Complication Rate ◽  
Longitudinal Direction ◽  
Functional Results ◽  
Fasciocutaneous Flap ◽  
Surgical Time ◽  
Cross Sectional ◽  
Skin Loss ◽  
Scrotal Reconstruction ◽  
The Mean

ABSTRACT Objective: to describe the use of a superomedial fasciocutaneous thigh flap for scrotal reconstruction in open areas secondary to the surgical treatment of perineal necrotizing fasciitis (Fournier’s gangrene). Methods: retrospective analysis of cases treated at the Plastic Surgery Service of Santa Casa de Misericórdia, São Paulo, from 2009 to 2015. Results: fifteen patients underwent scrotal reconstruction using the proposed flap. The mean age was 48.9 years (28 to 66). Skin loss estimates in the scrotal region ranged from 60 to 100%. Definitive reconstruction was performed on average 30.6 days (22 to 44) after the initial surgical treatment. The mean surgical time was 76 minutes (65 to 90) to obtain the flaps, bilateral in all cases. Flap size ranged from 10cm to 13cm in the longitudinal direction and 8cm to 10cm in the cross-sectional direction. The complication rate was 26.6% (four cases), related to the occurrence of segmental and partial dehiscence. Conclusion: the superomedial fasciocutaneous flap of thigh is a reliable and versatile option for the reconstruction of open areas in the scrotal region, showing adequate esthetic and functional results.

scholarly journals Investigation of Complex Structural Designing of Mobile Facilities for Shipbuilding in Lithuanian Sea Region

Mechanika ◽  
2021 ◽  
Vol 27 (3) ◽  
pp. 237-243
Author(s):  
Tadas ASTRAUSKAS ◽  
Michail SAMOFALOV
Keyword(s):  
Dynamic Analysis ◽  
Longitudinal Direction ◽  
Cross Sectional ◽  
Climatological Data ◽  
Second Stage ◽  
Third Stage ◽  
Calculation Results ◽  
Complex Structural ◽  
Mobile Facilities

In the paper, it is proposed to cover by a mobile moving facility the shipyard open site, in Klaipeda, Lithuania (the EU). The facility of 40 m span consists of transversal frames, which are arranged by the step of 6.0 m, and a system of braces. Two types of steel frames have been considered: trussed and continuous. The actions are specified according to the design codes (Eurocode 3) and climatological data. In dynamic analysis, the longitudinal direction is defined for an inertia action, simulating braking. For calculating, a special algorithm of three stages has been prepared. At the first stage, three calculation schemes of one transversal frame were created. For the proposed schemes of the mobile moving facility, the calculation of only a transversal frame is effective in the preliminary determination of the cross-sectional areas and of the total structural weight. At the second stage, the frames were joined by braces. A preliminary comparison of the calculation results of the models was carried out after the first and second stages of the analysis. At the third stage, the dynamic analysis was performed and the influence of the dynamic impact was estimated. Finally, we compared the calculation results of three different FEM models and chose the most appropriate one. To sum up the investigations, conclusions and recommendations are presented.

scholarly journals Pressure-driven flow in a thin pipe with rough boundary

2020 ◽  
Vol 71 (4) ◽  
Author(s):  
Elena Miroshnikova
Keyword(s):  
Fluid Flow ◽  
Longitudinal Direction ◽  
External Pressure ◽  
General Assumption ◽  
Rough Boundary ◽  
Local Behavior ◽  
Sectional Area ◽  
Cross Sectional ◽  
Incompressible Newtonian Fluid ◽  
Pressure Driven Flow

Abstract Stationary incompressible Newtonian fluid flow governed by external force and external pressure is considered in a thin rough pipe. The transversal size of the pipe is assumed to be of the order $$\varepsilon $$ ε , i.e., cross-sectional area is about $$\varepsilon ^{2}$$ ε 2 , and the wavelength in longitudinal direction is modeled by a small parameter $$\mu $$ μ . Under general assumption $$\varepsilon ,\mu \rightarrow 0$$ ε , μ → 0 , the Poiseuille law is obtained. Depending on $$\varepsilon ,\mu $$ ε , μ -relation ($$\varepsilon \ll \mu $$ ε ≪ μ , $$\varepsilon /\mu \sim \mathrm {constant}$$ ε / μ ∼ constant , $$\varepsilon \gg \mu $$ ε ≫ μ ), different cell problems describing the local behavior of the fluid are deduced and analyzed. Error estimates are presented.

Microstructural Properties of Common Yew and Norway Spruce Determined with Silviscan

IAWA Journal ◽  
2009 ◽  
Vol 30 (2) ◽  
pp. 165-178 ◽  
Author(s):  
Daniel Keunecke ◽  
Robert Evans ◽  
Peter Niemz
Keyword(s):  
Mechanical Behaviour ◽  
Mechanical Response ◽  
Elastic Anisotropy ◽  
Longitudinal Direction ◽  
Structural Features ◽  
Structure Property ◽  
Tangential Plane ◽  
Cross Sectional ◽  
X Ray ◽  
The Difference

Yew wood holds a special position within the softwoods with regard to its exceptional elasto-mechanical behaviour. Despite a relatively high density, it is highly elastic in the longitudinal direction (the modulus of elasticity is low and the stretch to break high). In the radial-tangential plane, its elastic anisotropy is clearly less pronounced compared to other softwoods such as spruce. Knowledge of the anatomical organisation of yew wood is an indispensable precondition for the correct interpretation of this conspicuous mechanical behaviour. The aim of this study, therefore, was to interpret the difference in elasto-mechanical behaviour of yew and spruce (as a reference) through their relative microstructures as measured by SilviScan, a technology based on X-ray densitometry, X-ray diffractometry and optical microscopy. This system is able to measure a variety of structural features in a wood sample. The results reveal that the elasto-mechanical response of yew is primarily due to large microfibril angles and a more homogeneous cross-sectional tissue composition (regarding tracheid dimensions and density distribution) compared to spruce. With respect to structure-property relationships, it was concluded that yew wood combines properties of normal and compression wood and therefore takes an intermediate position between them.

scholarly journals Resource Use Efficiency Among Aerobic and Conventional Rice Farms in Eastern Dry Zone of Karnataka: A Comparative Analysis

2021 ◽  
Vol 66 (3) ◽  
Author(s):  
Thejaswi Kumar
Keyword(s):  
Resource Use ◽  
Optimal Allocation ◽  
Rice Cultivation ◽  
Farm Size ◽  
Aerobic Rice ◽  
Resource Use Efficiency ◽  
Cross Sectional ◽  
Conventional Farms ◽  
Dry Zone ◽  
Use Efficiency

The efficiency with which farmers use available resources is very important for agricultural production. This study examines the comparative resource use efficiency (RUE) between aerobic and conventional rice farms in Eastern Dry Zone (Zone-5) of Karnataka. Cross-sectional data were collected from 100 rice cultivating farmers (50 in Aerobic farms and 50 in Conventional farms) using snow ball sampling technique. Cobb-Douglas production function, Marginal analysis of resource utilization, Data Envelopment Analysis (DEA) were some of the analytical tools used in the study. The mean aerobic farm size was 0.43 ha while in Conventional rice, it was 0.63 ha. The physical water use efficiency (WUE) in aerobic farms (3.84 q/acre inch) was higher than conventional farms (1.64 q/acre inch). Also, the economic WUE was higher in aerobic farms (1643.54 `/acre inch) compared to conventional farms (269.41 `/acre inch). RUE indicated that, resources were not optimally utilized in both Aerobic Rice Cultivation (ARC) and Conventional Rice Cultivation (CRC). Bullock labour, machine labour, seeds and irrigation were underutilized in ARC, whereas, FYM was underutilized in CRC indicating that usage of additional amount of these inputs leads to increase in the returns. The DEA revealed that aerobic rice cultivating farms were more technically and economically efficient compared to conventional rice cultivating farms. Effective policies to promote and create awareness about aerobic rice can boost the rice production and productivity sustainably. The focus should be given to optimal allocation of resources which enhances the farm productivity and returns

Tribological Study of Magnesium Alloys for Implant Applications

2014 ◽  
Author(s):  
Paul McGhee ◽  
Devdas Pai ◽  
Sergey Yarmolenko ◽  
Zhigang Xu ◽  
Sudheer Neralla ◽  
...  
Keyword(s):  
Extrusion Direction ◽  
Longitudinal Direction ◽  
Pure Magnesium ◽  
Optical Profilometry ◽  
Wear Properties ◽  
Biodegradable Implant ◽  
Cross Sectional ◽  
Wear Performance ◽  
Heat Treated ◽  
Wear Tests

Magnesium and its alloys have been found to potential candidates for biodegradable implant applications. However, magnesium and its alloys are broadly known to have poor tribological properties, but detailed specifics on wear performance are scarce. This research investigates the tribological characteristics on Mg-Zn-Ca-RE alloys and pure magnesium under as-cast and extruded conditions. Pure magnesium and Mg-Zn-Ca-RE alloys were hot extruded at 350°C and 400°C. Magnesium and Mg-Zn-Ca-Re alloy were also cast at 350°C and heat treated at 510°C. Directional wear properties were investigated using a CETR-UMT 2 microtribometer under unlubricated conditions in a reciprocating configuration for 120 cycles, with normal loads ranging from 0.5N–2.5N. Wear tests were conducted in directions: cross-sectional, longitudinal (along the extrusion direction) and transverse direction (perpendicular to the extrusion direction). Wear properties and friction properties were analyzed using a microtribometer, a mechanical stylus profiler, and microindentation. Surface morphology and microstructure were characterized using optical microscopy, scanning electron microscopy, and optical profilometry. The results show a lower wear rate in the transverse and cross-sectional direction compared to the longitudinal direction.

ASME B31.3 End of Life Considerations: Corrosion, Mechanical Strength, and Small Bore Geometry

2010 ◽  
Author(s):  
Dennis K. Williams
Keyword(s):  
Mechanical Strength ◽  
End Of Life ◽  
Longitudinal Direction ◽  
Careful Examination ◽  
Tabular Form ◽  
Sectional Area ◽  
Cross Sectional ◽  
Section Modulus ◽  
Process Piping ◽  
Thin Walled

This paper discusses the prescribed requirements contained within the ASME B31.3 Process Piping Code that specifically address the considerations of the design corrosion allowance when coincidently taken into account with the mechanical strength requirements of the same. In particular, the most significant effects of the least favorable corrosion allowances in combination with the mechanical strength requirements of ASME B31.3 are prevalent in thin walled, small bore piping of minimal geometric properties associated with the calculation of component stresses in the longitudinal direction. Careful examination of ASME B31.3 paragraph 302.4 reveals that the minimum required thickness of a piping component include allowances for corrosion and when taken in conjunction with paragraph 302.4.1, which requires that when necessary, the wall thickness shall be increased to prevent overstress, damage, or collapse, due to superimposed loads from handling or other causes. The effects of the aforementioned Code requirements are addressed and examples are presented for small bore piping (nps 2″ and below) that lead to a proposed small bore piping criteria for consideration by piping specification engineers. Finally, the results of the evaluation of various combinations of corrosion allowance and mechanical strength requirements in terms of metal cross sectional area and section modulus are presented in tabular form that support the proposed small bore piping criteria.

Development of a coupled numerical model for the interaction between transient fluid slosh and tank wagon vibration

2018 ◽  
Vol 233 (3) ◽  
pp. 568-582 ◽  
Author(s):  
Ahmad Rahmati-Alaei ◽  
Majid Sharavi ◽  
Masoud Samadian Zakaria
Keyword(s):  
Dynamic Response ◽  
Stokes Equations ◽  
Fluid Dynamic ◽  
Nonlinear Differential Equations ◽  
Coupled Model ◽  
Longitudinal Direction ◽  
Rolling Contact ◽  
Cross Sectional ◽  
Response Characteristics ◽  
Dynamic Response Characteristics

In this paper, a coupled model is developed to evaluate the effect of transient fluid slosh on the railway tank wagon dynamic vice versa. This model has computational complexity in solving the Navier–Stokes equations and nonlinear differential equations of tank wagon vibration with nonlinear wheel–rail contact. The coupled model can be used as an effective and robust tool compared to simplified models for assessing the stability of tank wagon. The transient fluid slosh model is analysed using the computational fluid dynamic method combined with the volume of fluid technique. The tank wagon dynamic model is solved using the fourth-order Runge–Kutta method based on the 19 degrees of freedom model with longitudinal, vertical, roll and pitch vibrations. The wheel–rail contact is considered according to nonlinear Hertzian and Kalker linear rolling contact theories. The fluid slosh model is validated using experimental data. The dynamic response characteristics of the partially filled railway tank wagon are investigated under straight-line braking manoeuvre using the coupled model. The results obtained from a parametric study, including the cross sectional shape and the filled volume show that the modified-oval cross section improves the dynamic response characteristics, which are attributed to its lower fluid's centre of gravity coordinate in the longitudinal direction and low lateral moment transfer of the fluid.

scholarly journals Biomechanics of the Mandible

2000 ◽  
Vol 11 (1) ◽  
pp. 123-136 ◽  
Author(s):  
T.M. van Eijden
Keyword(s):  
Bone Tissue ◽  
Sagittal Plane ◽  
Longitudinal Direction ◽  
Transverse Dimension ◽  
Vertical Shear ◽  
External Loading ◽  
Cross Sectional ◽  
Mandibular Bone ◽  
Biomechanical Behavior ◽  
Cross Sectional Dimension

In this review the biomechanical behavior of the mandibular bone tissue, and of the mandibular bone as a whole, in response to external loading is discussed. A survey is given of the determinants of mandibular stiffness and strength, including the mechanical properties and distribution of bone tissue and the size and shape of the mandible. Mandibular deformations, stresses, and strains that occur during static biting and chewing are reviewed. During biting and the powerstroke of mastication, a combination of sagittal bending, corpus rotation, and transverse bending occurs. The result is a complex pattern of stresses and strains (compressive, tensile, shear, torsional) in the mandible. To be able to resist forces and bending and torsional moments, not only the material properties of the mandible but also its geometrical design is of importance. This is reflected by variables like polar and maximum and minimum moments of inertia and the relative amount and distribution of bone tissue. In the longitudinal direction, the mandible is stiffer than in transverse directions, and the vertical cross-sectional dimension of the mandible is larger than its transverse dimension. These features enhance the resistance of the mandible to the relatively large vertical shear forces and bending moments that come into play in the sagittal plane.

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