J0230205 Numerical Study on tomographic Micro-visualization of Temperature Distribution by FEM-based Inverse Analysis applied to Optical Coherence Straingraphy

This paper presents a numerical study of the effect of peripheral wall conduction on combined free and forced laminar convection in hydrodynamically and thermally fully developed flow in horizontal rectangular channels with uniform heat input axially, In addition to the Prandtl number, the Grashof number Gr+, and the aspect ratio γ, a parameter Kp indicating the significance of wall conduction plays an important role in heat transfer. A finite-difference method utilizing a power-law scheme is employed to solve the system of governing partial differential equations coupled with the equation for wall conduction. The numerical solution covers the parameters: Pr = 7.2 and 0.73, γ = 0.5, 1, and 2, Kp = 10−4–104, and Gr+ = 0–1.37×105. The flow patterns and isotherms, the wall temperature distribution, the friction factor, and the Nusselt number are presented. The results show a significant effect of the conduction parameter Kp.

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Plasmonic chiral contrast agents for optical coherence tomography: numerical study

Optics Express ◽

10.1364/oe.19.014903 ◽

2011 ◽

Vol 19 (16) ◽

pp. 14903 ◽

Cited By ~ 4

Author(s):

Kalpesh B. Mehta ◽

Nanguang Chen

Keyword(s):

Optical Coherence Tomography ◽

Contrast Agents ◽

Numerical Study ◽

Optical Coherence

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Cooling Considerations for Design of a Radial Inflow Turbine

ASME 1977 International Gas Turbine Conference and Products Show ◽

10.1115/77-gt-82 ◽

1977 ◽

Author(s):

A. Hamed ◽

Y. Sheoran ◽

W. Tabakoff

Keyword(s):

Temperature Distribution ◽

Numerical Study ◽

Computer Time ◽

Coolant Temperature ◽

Internal Cooling ◽

Present Formulation ◽

Mechanical Integrity ◽

Cooling Design ◽

Time Savings ◽

Radial Inflow Turbine

A numerical study to determine the temperature distribution in the rotor of a radial inflow turbine is presented. Internal cooling passages are modeled in the present formulation in order to carry out solid and coolant temperature computations simultaneously resulting in a considerable computer time savings. The stresses due to centrifugal and thermal loadings are determined in an actual rotor and the effect of cooling design on its mechanical integrity is discussed.

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Numerical Study on the Effects of Relative Diameters on the Performance of Small Modular Reactors Driven by Natural Circulation

Energies ◽

10.3390/en13225881 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5881

Author(s):

Young Jin Kim ◽

Byung Jin Lee ◽

Kunwoo Yi ◽

Yoon Jae Choe ◽

Min Chul Lee

Keyword(s):

Temperature Distribution ◽

Steam Generator ◽

Flow Rate ◽

Numerical Study ◽

Natural Circulation ◽

Hydraulic Parameters ◽

Small Modular Reactors ◽

Velocity Changes ◽

Energy Equations ◽

Tube Pitch

Most of the small modular reactors (SMRs) under development worldwide present the same components: an integral reactor vessel with a low-positioned core as the heat source and a high-positioned steam generator as the heat sink. Moreover, some SMRs are being designed to be driven by natural circulation during normal power generation. This work focused on such designs and on their performance, considering the changes generated by the geometric and hydraulic parameters of the system. Numerical simulations using mass, momentum, and energy equations that considered buoyancy forces were performed to determine the effects of various geometric and hydraulic parameters, such as diameters and flow resistances, on the reactor’s performance. It was found that nonuniform diameters promote velocity changes that affect the natural circulation flow rate. Moreover, the reactor’s temperature distribution depends on the steam generator tube pitch. Therefore, the hydraulic diameters of the reactor’s coolant passages should be maintained as uniform as possible to obtain a more uniform temperature distribution and a larger mass flow rate in SMRs.

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Experimental and numerical study of the effect of coil structure on induction nitriding temperature field

Advances in Mechanical Engineering ◽

10.1177/1687814020938484 ◽

2020 ◽

Vol 12 (7) ◽

pp. 168781402093848

Author(s):

Kangjie Song ◽

Jing Guan ◽

Kunmao Li ◽

Jing Liu

Keyword(s):

Temperature Field ◽

Temperature Distribution ◽

Induction Heating ◽

Current Density ◽

Numerical Study ◽

Radial Temperature ◽

Current Frequency ◽

Variable Pitch ◽

Variable Radius ◽

Heating Efficiency

The axial and radial temperature distributions of an induction heating workpiece considerably impact the subsequent nitriding process. To obtain a satisfactory temperature distribution, an equal pitch coil, a variable pitch coil, and a variable radius coil were designed. Furthermore, an induction heating model that exhibits electromagnetic and temperature field coupling was established; thus, the effects of the current density and frequency on the heating efficiency and temperature distribution of the workpiece were analyzed and compared. In addition, an induction heating experiment was conducted to verify the model. According to the numerical results, the variable radius coil can reduce the axial temperature difference in comparison with equal pitch coil and variable pitch coil. Hence, the workpiece heated using the variable radius coil can achieve a better temperature distribution when compared with those heated by the equal pitch coil and variable pitch coil, with appropriate current density and current frequency values.

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