Showing papers on "Subcooling published in 1971"
TL;DR: Experimental transient boiling heat transfer in water for exponential heat inputs to thin metallic ribbons of 0.015 × 106 e t t 0 Btu/ft2h are compared with steady state predictions as mentioned in this paper.
42 citations
Patent•
14 Sep 1971
TL;DR: In this paper, a solution of glycol is used to avoid freezing point of water in an open Brayton cycle, where the working fluid is a dry gas, such as helium, or argon, or the like.
Abstract: In an open Brayton cycle, suction air is cooled by refrigeration to a predetermined temperature preferably to at least 50*F. below ambient air temperature. In the case of a conventional refrigeration system with refrigerant evaporation and condensation utilizes ambient air for condensation, the refrigeration is controlled to maintain a fixed temperature differential between the temperature at which the refrigerant evaporates and at which it condenses. If the temperature of the suction air is below the freezing point of water an aqueous solution of a water vapor pressure depressant such as glycol may be used under conditions which avoid, or control, freezing. This aqueous solution may be sprayed on cooling coils in indirect heat transfer or it may be cooled by circulation in indirect heat transfer and then used in direct contact to cool and condense water vapor from the suction air. The condensed water is vaporized, preferably with waste heat and injected into the compressed air stream. The refrigeration system may be a conventional one driven by the shaft or from the power network or it may be one which is driven by a system utilizing waste heat of the Brayton cycle exhaust gases. In a conventional system, multistage refrigeration is preferred. In the use of a solution of glycol the composition is maintained by distillation of water under pressure with utilization of the steam in the air stream between the Brayton cycle compressor and expander to improve output and thermal efficiency. The advantages of suction air refrigeration are especially marked when in combination with regeneration in the Brayton cycle and the advantages of regeneration are greater when in combination with suction air refrigeration. Still greater advantages result from a combination of suction air refrigeraton with both regeneration and gasification of fuels which contain sulfur and particulates. A portion of the refrigeration capacity for suction air cooling may be used for the cooling of electric generators and transformers. Suction refrigeration results in similar advantages when used with a closed Brayton cycle, wherein the working fluid is a dry gas, such as helium, or argon, or the like.
41 citations
38 citations
TL;DR: The behavior of the vapor wake is highly dependent upon the manner in which vapor is being formed on the forward portion of the sphere as discussed by the authors, and it is shown that film and transition boiling are as effective as nucleate boiling over the velocity range, 9.6-20.0 fps, in highly subcooled water.
34 citations
TL;DR: In this paper, the transient heating of a metal foil under water has been studied and both unstable and stable energy transfer processes have been shown to occur at temperatures above the nucleate boiling region and relevant quantitative heat flux data have been obtained.
28 citations
Patent•
18 Jan 1971
TL;DR: In this article, a system for transferring a cryogenic liquid from a storage vessel to a remote point of use at a constant temperature, pressure and flow rate is described, where the transfer tube is jacketed with a second tube along substantially its entire length and these tubes are enclosed in an evacuated jacket.
Abstract: A system for transferring a cryogenic liquid from a storage vessel to a remote point of use at a constant temperature, pressure and flow rate wherein the transfer tube is jacketed with a second tube along substantially its entire length and these tubes are enclosed in an evacuated jacket. Use of a nozzle in the second tube entry end causes the liquid entering the jacket to decrease in pressure and temperature thereby subcooling the liquid in the transfer tube to prevent said liquid from boiling. The jacketing fluid absorbs heat entering the transfer system from the atmosphere. Included in the system as accessories are an adaptor for attaching the system to the storage vessel in pressure tight relationship and flow control on the delivery end of the system.
22 citations
Patent•
23 Mar 1971
TL;DR: In this article, a system for recovering volatile combustible liquids from a vapor stream includes a vapor saturator for saturating and cooling the vapor stream with subcooled liquid product, a plurality of high pressure condenser stages, each such stage compressing and further cooling the liquid stream and condensing it by direct contact with sub cooled liquid product for forming liquid product and residual vapors, a terminal condensing stage for further condensing the residual liquid stream, means for venting the uncondensed vapors to atmosphere, a closed loop external refrigeration system for subcooling a portion
Abstract: A system for recovering volatile combustible liquids from a vapor stream includes a vapor saturator for saturating and cooling the vapor stream with subcooled liquid product, a plurality of high pressure condenser stages, each such stage compressing and further cooling the vapor stream and condensing it by direct contact with subcooled liquid product for forming liquid product and residual vapors, a terminal condensing stage for further condensing the residual vapors with subcooled liquid product, means for venting the uncondensed vapors to atmosphere, a closed loop external refrigeration system for subcooling a portion of the recovered liquid product, and pump means for recycling the subcooled liquid product to the saturator and the condenser stages, and a reservoir for collecting the uncycled liquid product.
12 citations
Patent•
25 Jun 1971
TL;DR: An air cooled heat exchanger, having U-tubes, for cooling gases or liquids as discussed by the authors, is connected at one end to an inlet manifold and at the other end to a collection manifold.
Abstract: An air cooled heat exchanger, having U-tubes, for cooling gases or liquids. Each tube is connected at one end to an inlet manifold and at the other end to a collection manifold. Cooling air flows co-currently with the condensing vapor or cooling liquid, thus preventing subcooling and freezing.
11 citations
01 Jan 1971
TL;DR: In this article, film boiling is an important aspect of cryogenic heat transfer and it is also important in conventional boilers, in quenching, and in similar applications, but it is difficult to apply it in the real world due to its low temperature.
Abstract: Because of its low temperature, a cryogenic fluid can film-boil by simply bringing it in contact with an ambient or room-temperature surface. As a result, film boiling is an important aspect of cryogenic heat transfer. It is also important in conventional boilers, in quenching, and in similar applications.
9 citations
TL;DR: In this paper, a digital model based on conservation of mass, energy and momentum was developed to support the phase relationship between void fraction and inlet flow rate in a natural circulation boiling water channel, and the effect of a sine-shaped heat flux on the stability of the system.
01 Jul 1971
TL;DR: Experimental data on subcooled and net-quality boiling heat transfer to low pressure water in electrically heated tubes is presented in this paper. But the authors focus on the transfer of boiling heat to water.
Abstract: Experimental data on subcooled and net-quality boiling heat transfer to low pressure water in electrically heated tubes
Patent•
12 Oct 1971TL;DR: In this article, a special heat exchanger in the condensate drain line is used to sub-cool the condenser and prevent instability or cavitation in the drain, and the subcooling liquid is taken from the moisture separator and reheater cycle.
Abstract: A moisture separator and reheater for separating moisture from wet steam and heating it using condensing-type tube bundles operating under saturated conditions incorporates a special heat exchanger in the condensate drain line to subcool the condensate and prevent instability or cavitation in the drain. The subcooling heat exchanger boils liquid taken from the moisture separator and reheater cycle to perform the condensate cooling.
TL;DR: In this article, the authors analyzed void fraction and inlet flowrate in a natural circulation boiling water loop in terms of their relative dependence using power spectra calculated by means of a special-purpose analogue computer.
TL;DR: In this article, a linear, one-dimensional, one channel model is presented which gives an analytical description of the frequency response and stability behavior of a boiling light water reactor or loop (both under forced or natural circulation, pressure-controlled or pressure-varying conditions) with respect to pertubations in reactivity (or heating power), primary steam flow (or system pressure), water inlet velocity or subcooling.
TL;DR: In this article, the hydrodynamic behavior of a boiling water reactor under transient conditions is described by an analytical model including nonlinear feedbacks of the time dependent system pressure and water level variations.