Numerical investigation of mixed convection heat transfer of a nanofluid in a circular enclosure with a rotating inner cylinder

Journal of Thermal Analysis and Calorimetry - In the present paper, mixed convection heat transfer of water–Al2O3 nanofluid in the space between two cylinders is investigated numerically. The...     

Experimental study on forced convection heat transfer of a nanofluid in a heat exchanger filled partially porous material

Journal of Thermal Analysis and Calorimetry - Heat transfer of MgO-EG nanofluid flowing in a double tube heat exchanger with an inner tube containing a partial porous material under laminar and...     

Numerical study of mixed convection heat transfer inside a vertical microchannel with two-phase approach

Journal of Thermal Analysis and Calorimetry - The current study investigates the laminar and two-phase nanofluid flow inside a two-dimensional rectangular microchannel with the ratio of length to...     

Numerical investigation of mixed convection heat transfer behavior of nanofluid in a cavity with different heat transfer areas

Journal of Thermal Analysis and Calorimetry - The main purpose of this research is the numerical modeling of laminar mixed convection heat transfer inside an open square cavity with different heat...     

Hybrid conduction,convection and radiation heat transfer simulation in a channel with rectangular cylinder

Journal of Thermal Analysis and Calorimetry - The innovation of this study is to investigate the combination effect of thermal radiation and convection in the hybrid heat transfer between solid and...     

Numerical study on flow and heat transfer characteristics of square cylinder with lateral sides extension effect

Journal of Thermal Analysis and Calorimetry - The present study analyses the effect of triangular and circular extensions on lateral sides of square cylinder in a confined domain. Two-dimensional...     

Numerical investigation of serrated fins on natural convection from concentric and eccentric annuli with different cross sections

Journal of Thermal Analysis and Calorimetry - In this paper, the effect of internal serrated fins and eccentricity on natural convection heat transfer between annular spaces with the equivalent...     

Numerical study of heat transfer enhancement from a heated circular cylinder by using nanofluid and transverse oscillation

Journal of Thermal Analysis and Calorimetry - Adding nanoparticles into the base fluid and oscillating the target surface are two passive and active techniques, respectively, for heat transfer...     

Numerical investigation of nanofluid laminar forced convection heat transfer between two horizontal concentric cylinders in the presence of porous medium

Journal of Thermal Analysis and Calorimetry - In this paper, the finite volume method is used to investigate the laminar forced convection of water–copper nanofluid between two porous...     

Effects of nanofluid and radiative heat transfer on the double-diffusive forced convection in microreactors

Journal of Thermal Analysis and Calorimetry - Understanding transport phenomena in microreactors remains challenging owing to the peculiar transfer features of microstructure devices and their...     

Numerical study on turbulent natural convection and radiation heat transfer of nanofluids in a differentially heated square enclosure

Journal of Thermal Analysis and Calorimetry - Due to the low performance observed during natural convection with fluids such as air and water, nanofluid research was carried out to analyse them for...     

Magnetic field effects on forced convection flow of a hybrid nanofluid in a cylinder filled with porous media: a numerical study

Journal of Thermal Analysis and Calorimetry - The magnetic field can serve as a proper controlling parameter for heat transfer and fluid flow; it can be also employed to maximize the thermodynamic...     

Energetic and entropic analyses of double-diffusive,forced convection heat and mass transfer in microreactors assisted with nanofluid

Journal of Thermal Analysis and Calorimetry - This paper investigates the energetic and entropic characteristics of a microchannel with thick walls. A first-order, catalytic chemical reaction is...     

Active and passive control of a galloping cylinder with heat transfer

Journal of Thermal Analysis and Calorimetry - Wind energy caused the transverse vibration of the beam, and the mechanical energy of vibration is transferred to electrical charge by piezoelectric...     

Orbital alignment dependence of electron transfer cross sections

his paper reports experimental results for the influence of target excitation and orbital alignment on the charge exchange process for the systems Ne⁺, Ar⁺-Na(3s,3p) for impact energies in the 1-15 keV range. The cross section parameters are found to depend sensitively on collision velocity and choice of projectile. Using earlier results by Aumayr et al (Z. Phys. D 6(1987) 145-153) for the Na(3s) target, the relative cross sections are put on an absolute scale. A strong dependence of the total electron transfer cross section on the target state is observed, most dramatically for low energy Ar⁺ impact for which the cross section for a Na(3p) target is more than 200 times larger than for Na(3s). Time-of-flight spectra show that electron transfer channels with energy defects near zero are strongly preferred. Cross section estimates based on the Demkov-Olson model account well for the major trends observed, but not for the detailed behavior.     

Orbital alignment dependence of electron transfer cross sections

This paper reports experimental and theoretical results for the influence of target excitation and orbital alignment on the charge exchange process for the system H⁺-Na(3s, 3p). The experimental velocity range covers for the first time the region around and beyond the matching velocity of 0.47 a.u. of the Na(3p) state, i.e. the velocity characteristic of the orbital motion of the valence electron. The cross section parameters are found to depend sensitively on collision velocity, with a qualitatively different behaviour below and above the matching velocity. The results for the orbital alignment dependence support the intuitive picture that, when going beyond the matching velocity, electron transfer becomes increasingly favoured when the orbital velocity of the active electron has a component parallel to the collision velocity. Agreement with earlier experimental and theoretical results at lower velocities is good and allows conclusions about the quality of theoretical approximations in the various velocity regimes.     

Removal of heat of adsorption from adsorbent by forced convection

An analytical mathematical model is used to investigate the effectiveness of forced convection for removal of the heat of adsorption from an adsorbent mass undergoing a differential adsorption process in a flow system. An example of such a process is measurement of gas adsorption kinetics using a differential adsorption bed. Isothermal operation may not be achieved even when a high gas flow rate is used, particularly if the sorption kinetics is relatively fast. Very small changes in the adsorbent temperature can cause significant departure from the isothermal uptake behavior when the heat of adsorption is moderately large. A criterion for validity of isothermal data analysis is given.     

Nonresonant charge transfer: Semiclassical calculation of differential cross sections

Charge transfer and elastic scattering differential cross sections in Li⁺ + Na are described in a two state model by a consequent application of semiclassical methods. The coupling model used is Demkov coupling; coupling parameters and potential curves are taken from calculations of other authors. The theoretical results, which contain no adjustable parameters, are in good agreement with experiment.     

Numerical study of nonlinear mixed convection inside stagnation-point flow over surface-reactive cylinder embedded in porous media

Nonlinear mixed convection of heat and mass in a stagnation-point flow of an impinging jet over a solid cylinder embedded in a porous medium is investigated by applying a similarity technique. The problem involves a heterogenous chemical reaction on the surface of the cylinder and nonlinear heat generation in the porous solid. The conducted analysis considers combined heat and mass transfer through inclusions of Soret and Dufour effects and predicts the velocity, temperature and concentration fields as well as the average Nusselt and Sherwood number. It is found that intensification of the nonlinear convection results in development of higher axial velocities over the cylinder and reduces the thickness of thermal and concentration boundary layers. Hence, consideration of nonlinear convection can lead to prediction of higher Nusselt and Sherwood numbers. Further, the investigation reveals that the porous system deviates from local thermal equilibrium at higher Reynolds numbers and mixed convection parameter.

     

Mixed convection heat transfer of a nanofluid in a lid-driven enclosure with two adherent porous blocks

Journal of Thermal Analysis and Calorimetry - Convective flow and heat transfer in an alumina/water nanofluid enclosure having two centered adherent porous blocks under the effect of moving upper...