Showing papers on "Fin (extended surface) published in 1972"
TL;DR: In this paper, a study of the heat transfer from highly dissociated combustion products to a cold surface has been undertaken, where convective heat transfer coefficients have been determined experimentally at the stagnation point of a blunt body immersed in the flames of several common fuel gases burning with pure oxygen.
45 citations
TL;DR: In this article, the authors extended the theory to cover the case of the inclined cell and the vertical cell and showed that convection must be initiated for any temperature gradient to be established between the absorber plate and the glass cover plate.
37 citations
TL;DR: In this article, the problem of combined forced and free-convection heat transfer from a thin needle in a uniform external stream is considered, and the series and local similarity solutions have been discussed.
Abstract: The problem of laminar combined forced and free‐convection heat transfer from a thin needle in a uniform external stream is considered. The series and local similarity solutions have been discussed.
37 citations
Patent•
18 Sep 1972
TL;DR: In this article, an apparatus is provided for indicating the temperature of a surface or heat source by employing a single liquid crystal composition which is at varying distances from the surface, with the first and second means in heat exchanging relationship.
Abstract: An apparatus is provided for indicating the temperature of a surface or heat source by employing a single liquid crystal composition which is at varying distances from the surface. A first means is provided for heat exchanging with said surface. A second means is provided for heat exchanging with the ambient environment, with the first and second means in heat exchanging relationship. At least a portion of said second means is coated with a liquid crystal composition extending away from said first means. The apparatus is useful in combination with appliances or apparatii which are at elevated temperatures, particularly those which reach temperatures in excess of that which burns the skin, such as wood burning tools, soldering irons, electric ranges, conduits for high temperature fluids, and the like.
28 citations
TL;DR: Wind-tunnel Magnus data obtained to date on canted fin configurations may be invalid in that a severe normal force interaction may be present, so in general best to remove the interaction by subtracting the zero spin data at each angle of attack.
Abstract: Conclusions Wind-tunnel Magnus data obtained to date on canted fin configurations may be invalid in that a severe normal force interaction may be present. Although it may be possible in some cases to correct for this interaction, it is in general best to remove the interaction by subtracting the zero spin data at each angle of attack. This requires a system in which the model can be kept at zero spin during an angle of attack sweep of the configuration.
25 citations
TL;DR: In this article, a solution for the unsteady state temperature distribution in a fin of constant area dissipating heat only by convection to an environment of constant temperature is obtained.
Abstract: A solution for the unsteady-state temperature distribution in a fin of constant area dissipating heat only by convection to an environment of constant temperature, is obtained. The partial differential equation is separated into an ordinary differential equation with position as the independent variable, and a partial differential equation with position and time as the independent variables. The problem is solved for either a step function in temperature or a step function in heat flow rate, for zero time, at one boundary while the other boundary is insulated. The initial condition is taken as an arbitrary constant. The unspecified boundary values (temperature or heat flow rate) are presented for both cases by utilizing dimensionless plots. Experimental verification is presented for the case of constant heat flow rate boundary condition.
20 citations
TL;DR: In this article, an analytical analysis of the heat and momentum transfer of a binary mixture of gases flowing in a parallel plate channel where mass injection occurs at one wall is presented. But the authors assume that the flow is steady, laminar, and incompressible.
10 citations
Dissertation•
01 Jan 1972
8 citations
Patent•
31 Jul 1972
TL;DR: In this paper, the heat transfer contour of the tools may be obtained by varying parameters such as material, mass, density, specific heat and absorptivity over the contact area of the tool.
Abstract: Radiantly heated tools are used for bonding leads to an array of circuit paths. The heat transfer characteristics of the tools over their area of contact with the leads and circuit paths cause a profile or contour to be formed which matches the heat capacity profile or contour of the array to the heat output contour of a heat source. The heat transfer contour of the tools may be obtained by varying parameters such as material, mass, density, specific heat and absorptivity over the contact area of the tools.
7 citations
TL;DR: In this article, the authors used a computer program to solve the heat conduction equation for some surfaces having transverse ribs, and the results showed that the performance of geometrically identical surfaces, as judged by, say, the peak surface temperature, may differ significantly.
7 citations
TL;DR: It has been shown that the heat conduction equation could be made linear by choosing the integrated conductivity, instead of the temperature, as the unknown; unfortunately, the boundary conditions as mentioned in this paper.
Abstract: It has been shown that the heat conduction equation could be made linear by choosing the integrated conductivity, instead of the temperature, as the unknown; unfortunately, the boundary conditions ...
TL;DR: In this paper, an approximate method for calculating the temperature profile of a thin perforated fin was proposed for calculating its temperature profile, and the method was applied to a single fin.
Abstract: An approximate method is proposed for calculating the temperature profile of a thin perforated fin.
TL;DR: In this article, a method was proposed for determining the heat transfer coefficient from instantaneous temperature values at points inside a plate, a hollow cylinder, or a hollow sphere during heatup.
Abstract: A method is proposed for determining the heat transfer coefficient from instantaneous temperature values at points inside a plate, a hollow cylinder, or a hollow sphere during heatup.
TL;DR: In this paper, the authors derived the heat conduction constraint on the growth of a droplet taking into account the heat transfer associated with mass transfer, and requiring total energy conservation.
Abstract: The heat conduction constraint on the growth of a droplet is re-derived taking into account the heat transfer associated with mass transfer, and requiring total energy conservation. The derived constraint is identical with that given by Maxwell, who simply equated the rate of latent heat release to the heat conduction associated with a temperature gradient.
TL;DR: In this paper, visual observations concerning the distribution of static pressure, of the transverse velocity to longitudinal velocity ratio, of flow rates, and of the local heat transfer coefficient in a system of channels with spills are presented.
Abstract: Results are shown of visual observations concerning the distribution of static pressure, of the transverse velocity to longitudinal velocity ratio, of the flow rates, and of the local heat transfer coefficient in a system of channels with spills.
Patent•
23 Aug 1972
TL;DR: A finned heat exchange tube as mentioned in this paper is a tube with a helical, radially-extending fin having a flange 5 which extends at right angles to the fin, and is wound around and in contact with the tube and is retained thereon by a rectangular section wire 4 wound under tension to overlie the fin flanges 5 and welded at each end thereof to the tube wall.
Abstract: 1286241 Finned heat exchange tubes BRITISH STEEL CORP 30 Sept 1969 [4 July 1968] 32040/68 Heading F4S A finned heat exchange tube is provided with a helical, radially-extending fin 2 having a flange 5 which extends at right angles to the fin. The fin is wound around and in contact with the tube and is retained thereon by a rectangular section wire 4 wound under tension to overlie the fin flanges 5 and welded at each end thereof to the tube wall. The wire may also be secured intermediate its ends to the tube by welding through the fin flange 5, or by casting a block of low melting point alloy over the fin. The fin is slit at intervals along its length so that it is divided into a number of separate radially extending fin members.
TL;DR: In this paper, the heat transfer by a turbulent flow of radiating gaseous suspension in a circular tube with constant wall temperature, taking account of the thermal radiation to both particulate and carrier phases simultaneously, was evaluated.
Abstract: While a solid suspension medium acquires superior heat transfer characteristics under the condition of high temperature and high heat flux such as encountered with the HTGR, a clear knowledge of the heat transfer mechanism and the quantitative evaln analysis was aseous suspension flow 1s presented to facilperformed on the heat transfer by a turbulent flow of radiating gaseous suspension in a circular tube with constant wall temperature, taking account of the thermal radiation to both particulate and carrier phases simultaneously. The comp1exities of the geometry and the flow mechanics are described by introducing plausible assumptions. The results reveal greatly improved heat transfer on account not only of the increased heat capacily of the flowing medium but also of the enhanced radiative heat transfer caused by the increment of the optical thickness for radiation. The results obtained here are also compared with those of a single phase flow of radiating medium, and a simplified treatment of heat transfer by gaseous suspension flow is presented to facilitate practical calcu1ations. (auth)
TL;DR: In this article, an experimental study concerned with the heat transfer during various modes of air flow through narrow channels (Re = 360-32,000) was conducted, and the channel dimensions as well as the conditions were established which correspond to a definite effect of natural convection on heat transfer.
Abstract: Results are shown of an experimental study concerned with the heat transfer during various modes of air flow through narrow channels (Re = 360–32,000). The channel dimensions as well as the conditions are established which correspond to a definite effect of natural convection on the heat transfer.
Patent•
11 Jan 1972
01 Jan 1972
TL;DR: In this article, an active cooling scheme in which discrete cooling passages are used was investigated and the accuracy of the heat transfer rate predictions by these approximations was evaluated by means of both experimental and numerical investigations.
Abstract: An active cooling scheme in which discrete cooling passages are used was investigated. In this scheme, the coolant passages are placed perpendicular to the main stream direction. Streamwise temperature oscillations result from the highly cooled regions, near the coolant channels, being next to regions not directly cooled between the channels. The accuracy of the heat transfer rate predictions by these approximations was evaluated by means of both experimental and numerical investigations. Experiments were conducted at free stream Mach number of 6 with several cooling passages. Heat transfer measurements were made and corresponding theoretical analysis were performed for comparison in evaluating both local and overall deviations in the heat transfer rate.
TL;DR: In this paper, the authors considered the hydrodynamic and thermal boundary layers for the flow represented by Fig. 2 and obtained approximate formulas for the friction and the heat transfer, assuming that W≪U 0.
Abstract: We consider the hydrodynamic and thermal boundary layers for the flow represented by Fig. 2. Assuming that W≪U0, we obtain approximate formulas for the friction and the heat transfer.