Showing papers in "International Journal of Heat and Fluid Flow in 1986"

TL;DR: Optical techniques for measuring large numbers of simultaneous velocity vectors in two-and three-dimensional regions of fluid flows are reviewed in this article, which provides spatial information of the type that is available from flow visualization with accuracy approaching that of single-point methods such as laser Doppler velocimetry and hot wire.

TL;DR: In this article, the application of an external blood flowmeter, an ultrasonic Doppler shift detection device, to the one-dimensional velocity profile measurement of the general flow of water was studied.

TL;DR: In this paper, a series of numerical experiments concerning the phenomenon of natural convection in a two-layer composite system heated from below is reported, and the numerical solutions are based on the full equations for time-dependent flow, and document the main features of the flow at Rayleigh numbers several orders of magnitude above critical value.

TL;DR: In this article, a modified Bingham plastic model was proposed to represent the flow of a liquid-gas foam, with the addition of a fluid-rich slip layer caused by bubble migration away from a solid surface.

TL;DR: In this paper, steady-state natural convection heat transfer in rectangular enclosures, that are vertically divided into a region filled with fluid and another filled with a fluid-saturated porous medium, is investigated.

TL;DR: In this paper, the authors studied the dynamics of cavities produced in cavitating flow confined in a duct and found that the time for a cavity to collapse was three times greater than expected from Rayleigh's classical theory.

TL;DR: In this paper, velocity, pressure and heat transfer measurements have been made inside a rotating cavity with a radial inflow of fluid for a wide range of flow rates and rotational speeds.

TL;DR: In this article, a wide range of geometric and aerodynamic parameters were systematically studied, with measurements being made of pressure losses, turbulence intensities, spectra, auto-correlations and length scales.

TL;DR: In this article, the effects of a sound field on the time-averaged heat transfer from, and drag on, a flat plate with a square leading edge having separated and reattached flow is reported.

TL;DR: In this paper, the authors extended Fritz's analysis on the maximum bubble volume during boiling to the boiling process in the presence of a uniform electric field and found that the bubble departure size decreases with increase in electric field strength and the dielectric constant of the boiling liquid.

TL;DR: In this article, a finite element method was used to solve the full Navier-Stokes and energy equations for the problems of laminar flow and heat transfer characteristics of air around three isothermal heated horizontal cylinders in a staggered tube bank and around four isothermal heating cylinders in an in line tube bank.

TL;DR: In this article, a general statement of the Navier-Stokes equations in cylindrical coordinates written in a form to account for turbulent velocity components is presented, and a technique for the solution of the resulting elliptic equations and associated boundary conditions is presented.

TL;DR: In this paper, a simple empirical formula was obtained from which it was possible to predict the length of the entry region of a pipe, and the onset of the increase in turbulence intensity at the core, which marks the start of transition from flat plate flow to pipe flow, was found at a particular Reynolds number, based on distance into pipe, of about 3.15×10 6.

TL;DR: In this article, it was shown that the effect of scale, intensity and Reynolds number on the drag coefficient of spheres is at least as important as its intensity in determining the drag coefficients of spheres, particularly when macroscale and sphere diameter are comparable.

TL;DR: In this article, the effects of turbulent air jets on convective heat transfer to the stagnation region of a circular cylinder were investigated. And the effect of turbulence in increasing the stagnation point velocity gradient has also been evaluated.

TL;DR: In this paper, an experimental and numerical study of laminar natural convection in a water-filled enclosure with an aspect ratio of 2:1 was conducted, where two opposing vertical walls were held at different uniform temperatures.

TL;DR: In this article, a Plexiglas laboratory pump with rectangular cross sections was tested and volute velocities were measured with a laser velocimeter, which indicated that the proper general flow characteristics were achieved with the flow swirler but the unsteady "jet-wake" regions were eliminated.

TL;DR: In this paper, it was shown that there exist three isentropic exponents, having different values, corresponding to the three possible pairs of variables selected among temperature, pressure and volume.

TL;DR: In this article, the stability of free convection flow inside a rectangular tilted enclosure was investigated by measuring the temperature within the air and the transition from a stationary to a non-stationary state was detected by measurement of the temperature.

TL;DR: In this article, an experimental study of natural convection in a parallelepipedal enclosure induced by a single vertical wall is described, where temperature and flow measurements were performed in the high Rayleigh number regime (10 10 Ra 10 ) by using water as the working fluid.

TL;DR: Morevoer et al. as mentioned in this paper developed a new model allowing the calculation of local resistance of gas-liquid two-phase flow through an orifice, which can also meet the general requirements of engineering design.

TL;DR: In this paper, mean flow and turbulence measurements were made in the separated region and around a vertical cylindrical obstacle submerged in a turbulent boundary layer and mounted on an irregularly rough surface.

TL;DR: In this paper, an experimental investigation on a NACA 0018 aerofoil oscillating about mean incidence angle of 0° with amplitude of 16° was carried out and the results showed an increase in incidence angle at which stall occurs, in maximum lift coefficient, and in the extent of hysteresis loop, with increase in reduced frequency.

TL;DR: In this article, the influence of low-frequency harmonic oscillations on the natural convection occuring at vertical walls of a ship tank has been investigated by the use of potential flow theory.

TL;DR: For turbulent swirling flow in a duct of circular cross-section, the time-averaged Navier-Stokes and continuity equations are written, and by introducing into these equations the longitudinal vorticity ω and stream-function ψ, they are cast in a form amenable to digital computer using well known finite difference techniques as discussed by the authors.

TL;DR: In this paper, the authors analyzed doubly connected ducts, bounded externally by a circle and internally by a regular polygon of various shapes, using the finite element method. And they compared their results with previous results available in the literature.

TL;DR: Particle paths and erosion have been calculated for the observed three-dimensional flow in a stationary, low speed cascade in order to illustrate the effects of secondary flow as discussed by the authors, where secondary flow was found to move particles either to or from the endwalls, resulting in both endwall erosion and the trapping of particles in the endwall boundary layers.

TL;DR: In this article, a general asymptotic expression based on the assumption of high Prandtl number was derived through a simple integral analysis, for a speedy and accurate estimation of the forced convection heat transfer from external surfaces to non-Newtonian power law fluids.