Heat Capacity near the Superfluid Transition inHe4at Saturated Vapor Pressure

1971 ◽  
Vol 3 (2) ◽  
pp. 696-716 ◽  
Author(s):  
Guenter Ahlers
Keyword(s):  
Heat Capacity ◽  
Vapor Pressure ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Superfluid Transition

scholarly journals Study on a Quaternary Working Pair of CaCl2-LiNO3-KNO3/H2O for an Absorption Refrigeration Cycle

Entropy ◽  
2019 ◽  
Vol 21 (6) ◽  
pp. 546 ◽  
Author(s):  
Yiqun Li ◽  
Na Li ◽  
Chunhuan Luo ◽  
Qingquan Su
Keyword(s):  
Heat Capacity ◽  
Crystallization Temperature ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Specific Enthalpy ◽  
Refrigeration Cycle ◽  
Absorption Refrigeration ◽  
Evaporation Temperature ◽  
Corrosion Rates ◽  
Specific Entropy

When compared with LiBr/H2O, an absorption refrigeration cycle using CaCl2/H2O as the working pair needs a lower driving heat source temperature, that is, CaCl2/H2O has a better refrigeration characteristic. However, the crystallization temperature of CaCl2/H2O solution is too high and its absorption ability is not high enough to achieve an evaporation temperature of 5 °C or lower. CaCl2-LiNO3-KNO3(15.5:5:1)/H2O was proposed and its crystallization temperature, saturated vapor pressure, density, viscosity, specific heat capacity, specific entropy, and specific enthalpy were measured to retain the refrigeration characteristic of CaCl2/H2O and solve its problems. Under the same conditions, the generation temperature for an absorption refrigeration cycle with CaCl2-LiNO3-KNO3(15.5:5:1)/H2O was 7.0 °C lower than that with LiBr/H2O. Moreover, the cycle’s COP and exergy efficiency with CaCl2-LiNO3-KNO3(15.5:5:1)/H2O were approximately 0.04 and 0.06 higher than those with LiBr/H2O, respectively. The corrosion rates of carbon steel and copper for the proposed working pair were 14.31 μm∙y−1 and 2.04 μm∙y−1 at 80 °C and pH 9.7, respectively, which were low enough for engineering applications.

scholarly journals Effects of nanoparticles on hydraulic cavitation

2018 ◽  
Vol 240 ◽  
pp. 03004
Author(s):  
Min-rui Chen ◽  
Jin-yuan Qian ◽  
Zan Wu ◽  
Chen Yang ◽  
Zhi-jiang Jin ◽  
...  
Keyword(s):  
Vapor Pressure ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Geometric Model ◽  
Pressure Ratio ◽  
Perforated Plate ◽  
Significant Parameter ◽  
Operation Conditions ◽  
Small Bubbles ◽  
Crucial Condition

When liquids flowing through a throttling element, such as a perforated plate, the velocity increases and the pressure decreases. If the pressure is below the saturated vapor pressure, the liquid will vaporize into small bubbles, which is called hydraulic cavitation. In fact, vaporization nucleus is another crucial condition for vaporizing. The nanoparticles contained in the nanofluids play a significant role in vaporization of liquids. In this paper, the effects of the nanoparticles on hydraulic cavitation are investigated. Firstly, a geometric model of a pipe channel equipped with a perforated plate is established. Then with different nanoparticle volume fractions and diameters, the nanofluids flowing through the channel is numerically simulated based on a validated numerical method. The operation conditions, such as the temperature and the pressure ratio of inlet to outlet, are the considered variables. As a significant parameter, cavitation numbers under different operation conditions are achieved to investigate the effects of nanoparticles on hydraulic cavitation. Meanwhile, the contours are extracted to research the distribution of bubbles for further investigation. This study is of interests for researchers working on hydraulic cavitation or nanofluids.

Porous Hydroxyapatite with Tailored Crystal Surface Prepared by Hydrothermal Method

2005 ◽  
Vol 284-286 ◽  
pp. 353-356 ◽  
Author(s):  
Koji Ioku ◽  
Giichiro Kawachi ◽  
Nakamichi Yamasaki ◽  
Hirotaka Fujimori ◽  
Seishi Goto
Keyword(s):  
Aspect Ratio ◽  
Vapor Pressure ◽  
Hydrothermal Method ◽  
Saturated Vapor Pressure ◽  
Crystal Surface ◽  
Saturated Vapor ◽  
Pure Water ◽  
Porous Hydroxyapatite ◽  
Exposure Method ◽  
The Mean

Porous plates of hydroxyapatite (Ca10(PO4)6(OH)2; HA) with about 0.5 to 5 mm in thickness and porous HA granules of about 40 µm to 1 mm in size with tailored crystal surface were prepared by the hydrothermal vapor exposure method at the temperatures above 105 °C under saturated vapor pressure of pure water. Porous HA plates with about 75 % porosity prepared at 120 °C were composed of rod-shaped crystals of about 20 µm in length. Porous HA granules prepared at 160 °C were also composed of rod-shaped crystals of about 20 µm in length with the mean aspect ratio of 30. These crystals were elongated along the c-axis. Rod-shaped HA crystals were locked together to make micro-pores of about 0.1 to 0.5 µm in size. Both of materials were nonstoichiometric HA with calcium deficient composition. These materials must have the advantage of adsorptive activity, because they had large specific crystal surface and much micro-pores.

scholarly journals Application of a Micro-Flow Regulating Valve in Saturated Vapor Pressure Measurements

Daxue Huaxue ◽  
2021 ◽  
Vol 0 (0) ◽  
pp. 2107062-0
Author(s):  
Shuai Zhang ◽  
Jian Zhang ◽  
Shaowei Bian ◽  
Yaping Zhao ◽  
Li Shen ◽  
...  
Keyword(s):  
Vapor Pressure ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Pressure Measurements ◽  
Micro Flow ◽  
Vapor Pressure Measurements

IMPROVING THE DESIGN OF THE FILM DEODORIZER

2019 ◽  
Author(s):  
О.И. НИКОНОВ ◽  
Н.Н. БЕЛИНА ◽  
А.В. ГУКАСЯН
Keyword(s):  
Vapor Pressure ◽  
Thin Layer ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Live Steam ◽  
Deodorization Temperature ◽  
Improved Design

Приведены характеристики содержащихся в масле одорирующих веществ. Проведен анализ конструкции существующих дезодораторов. Рассчитаны параметры, влияющие на процесс дезодорации в тонком слое. Получена зависимость давления насыщенных паров от температуры дезодорации. На основе проведенных расчетов предложены способы интенсификации процесса дезодорации. Предложена усовершенствованная конструкция дезодоратора, позволяющая интенсифицировать процесс дезодорации: сократить время и уменьшить расход острого пара. The characteristics of the odorizing substances contained in the oil are given. An analysis of the design of already existing deodorizers is given. The parameters affecting the deodorization process in a thin layer are calculated. The dependence of the saturated vapor pressure on the deodorization temperature was obtained. On the basis of the calculations performed, methods for intensifying the deodorization process have been proposed. The proposed improved design of the deodorizer, which allows intensify the deodorization process: to reduce the time and reduce the consumption of live steam.

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