Journal articles: 'Vapour expansion'

1

Ahmed, Aram Mohammed, and Attila R. Imre. "The effect of recuperator on the efficiency of ORC and TFC with very dry working fluid." MATEC Web of Conferences 345 (2021): 00012. http://dx.doi.org/10.1051/matecconf/202134500012.

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Organic Rankine Cycles (ORC) and Trilateral Flash Cycles (TFC) are very similar power cycles; ideally, they have a reversible adiabatic (isentropic) compression, an isobaric heating, an isentropic expansion and an isobaric cooling. The main difference is that for ORC, the heating includes the full evaporation of the working fluid (prior expansion); therefore, the expansion starts in a saturated or dry vapour state, while for TFC, the heating terminates upon reaching the saturated liquid states. Therefore, for TFT, expansion liquid/vapour state (in bubbly liquid or in vapour dispersed with droplets), requiring a special two-phase expander. Being ORC a more “complete” cycle, one would expect that its thermodynamic efficiency is always higher than for a TFC, between the same temperatures and using the same working fluids. Surprisingly, it was shown that for very dry working fluids, the efficiency of TFC can exceed the efficiency of basic (i.e. recuperator- and superheater-free) ORC, choosing sufficiently high (but still subcritical) maximal cycle temperature. Therefore in these cases, TFC (having a simpler heat exchange unit for heating) can be a better choice than ORC. The presence of a recuperator can influence the situation; by recovering the proper percentage of the remaining heat (after the expansion), the efficiency of ORC can reach and even pass the efficiency of TFC.

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Saini, D. K., A. Baruah, and G. Sachdeva. "Vapour compression system analysis undergoing expansion in an ejector." Journal of Physics: Conference Series 1240 (July 2019): 012131. http://dx.doi.org/10.1088/1742-6596/1240/1/012131.

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Mielczarek, Z. A., and T. J. Trojanowski. "Refrigerant vapour superheat in direct-expansion air cooling coils." International Communications in Heat and Mass Transfer 14, no. 3 (May 1987): 341–46. http://dx.doi.org/10.1016/0735-1933(87)90035-2.

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Miyauchi, Masato, Takumi Watanabe, Daiki Hoshi, and Tomonori Ohba. "Irreversible adsorption of acidic, basic, and water gas molecules on calcium-deficient hydroxyapatite." Dalton Transactions 48, no. 47 (2019): 17507–15. http://dx.doi.org/10.1039/c9dt03704g.

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Guardone, Alberto, Piero Colonna, Emiliano Casati, and Enrico Rinaldi. "Non-classical gas dynamics of vapour mixtures." Journal of Fluid Mechanics 741 (February 13, 2014): 681–701. http://dx.doi.org/10.1017/jfm.2013.13.

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AbstractThe non-classical gas dynamics of binary mixtures of organic fluids in the vapour phase is investigated for the first time. A predictive thermodynamic model is used to compute the relevant mixture properties, including its critical point coordinates and the local value of the fundamental derivative of gas dynamics $\Gamma $. The considered model is the improved Peng–Robinson Stryjek–Vera cubic equation of state, complemented by the Wong–Sandler mixing rules. A finite thermodynamic region is found where the nonlinearity parameter $\Gamma $ is negative and therefore non-classical gas dynamics phenomena are admissible. A non-monotone dependence of $\Gamma $ on the mixture composition is observed in the case of binary mixtures of siloxane and perfluorocarbon fluids, with the minimum value of $\Gamma $ in the mixture being always larger than that of its more complex component. The observed dependence indicates that non-ideal mixing has a strong influence on the gas dynamics behaviour, either classical or non-classical, of the mixture. Numerical experiments of the supersonic expansion of a mixture flow around a sharp corner show the transition from the classical configuration, exhibiting an isentropic rarefaction fan centred at the expansion corner, to non-classical ones, including mixed expansion waves and rarefaction shock waves, if the mixture composition is changed.

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Duplat, Jérôme. "Dynamics of expansion and collapse of explosive two-dimensional bubbles." Journal of Fluid Mechanics 859 (November 22, 2018): 677–90. http://dx.doi.org/10.1017/jfm.2018.804.

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An explosive gas mixture of hydrogen and oxygen is introduced in liquid water between two horizontal walls, forming a flat cylindrical bubble. Ignition and explosion of the bubble lead to a large depressurized cavity that finally implodes. We investigate the dynamics of the bubble collapse, which is qualitatively similar to the collapse of a spherical bubble. It exhibits a slightly weaker singularity than for spherical bubbles. We also analyse the explosion process. Starting with an initial radius $R_{0}$, the bubble reaches a maximal radius $R_{max}$ that depends on the gap thickness $h$ between the two walls: for a thinner gap, the condensation of water vapour is more efficient, the overpressure consecutive to the combustion is weaker, and its duration is shorter. This leads to a smaller maximal radius $R_{max}$. An indirect measurement of the transport coefficient of hot water vapour can be inferred from this observation.

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Arshed, G. M., S. Z. Shuja, B. S. Yilbas, and M. O. Budair. "Transient Helium Jet Expansion Into Stagnant Air in Relation to Laser Drilling." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 219, no. 7 (July 1, 2005): 667–83. http://dx.doi.org/10.1243/095440605x31517.

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Transient helium jet expansion into a stagnant air environment is modelled to resemble the laser vapour ejection from the cavity during the drilling process. As the metal vapour properties are not known, helium is employed while the previously measured jet inlet velocity profiles are introduced in the simulations. A numerical scheme employing a control volume approach is used to discretize the governing equations of flow. The predictions are validated through a case study associated with an incompressible transient jet flow. It is found that the jet inlet profile influences considerably the self-similar behaviour of the jet. Moreover, the jet expands radially in the early period while as time progresses, the axial penetration of the jet becomes high.

8

Sarkar, Jahar. "Exergy analysis of vortex tube expansion vapour compression refrigeration system." International Journal of Exergy 13, no. 4 (2013): 431. http://dx.doi.org/10.1504/ijex.2013.058101.

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Liu, Yefeng, and Jun Yu. "Review of vortex tube expansion in vapour compression refrigeration system." IOP Conference Series: Earth and Environmental Science 153 (May 2018): 032021. http://dx.doi.org/10.1088/1755-1315/153/3/032021.

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Gouin, Henri, and Pierre Seppecher. "Temperature profile in a liquid–vapour interface near the critical point." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 473, no. 2204 (August 2017): 20170229. http://dx.doi.org/10.1098/rspa.2017.0229.

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Thanks to an expansion with respect to densities of energy, mass and entropy, we discuss the concept of thermocapillary fluid for inhomogeneous fluids. The non-convex state law valid for homogeneous fluids is modified by adding terms taking account of the gradients of these densities. This seems more realistic than Cahn and Hilliard’s model which uses a density expansion in mass-density gradient only. Indeed, through liquid–vapour interfaces, realistic potentials in molecular theories show that entropy density and temperature do not vary with the mass density as it would do in bulk phases. In this paper, we prove using a rescaling process near the critical point, that liquid–vapour interfaces behave essentially in the same way as in Cahn and Hilliard’s model.

11

Goyal, Kunal, R. V. Nanditta, Potteli Dharma Teja, S. Malarmannan, and G. Manikandaraja. "Analysis of vapor compression refrigeration system employing tetrafluroethane and difluroethane as refrigerants." Journal of Physics: Conference Series 2054, no. 1 (October 1, 2021): 012054. http://dx.doi.org/10.1088/1742-6596/2054/1/012054.

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Abstract The axiomatic effects of ozone layer depletion have caused additional damage in the last few decades. The accretion in greenhouse gases has transformed to take cardinal steps immediately. The concoct blend of 1,1,1,2 Tetrafluroethane (R134a) and 1,1, Difluroethane (R152) a was tested in a vapour compression refrigeration system as these are non-toxic, eco-friendly, non-flammable and non-corrosive. Experimental performance analysis of vapor compression refrigeration system using R134a and blends of R152a and R134a is done for different dimensions of expansion valves. Various parameters like coefficient of performance (COP), refrigerating effect and compressor work were analyzed. Refrigeration effect and compressor work of R134a was higher than R152a. COP value was reliable for 60/40 ratio of R152a and R134a and maximum COP was achieved with the blend of 90/10 ratio in the first expansive coil. These aberrant results could be overcome by amalgamation of R134a and R152a as the discharge temperature of R152a is effectively controlled by blending.

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Imre, Attila R., Réka Kustán, and Axel Groniewsky. "Thermodynamic Selection of the Optimal Working Fluid for Organic Rankine Cycles." Energies 12, no. 10 (May 27, 2019): 2028. http://dx.doi.org/10.3390/en12102028.

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A novel method proposed to choose the optimal working fluid—solely from the point of view of expansion route—for a given heat source and heat sink (characterized by a maximum and minimum temperature). The basis of this method is the novel classification of working fluids using the sequences of their characteristic points on temperature-entropy space. The most suitable existing working fluid can be selected, where an ideal adiabatic (isentropic) expansion step between a given upper and lower temperature is possible in a way, that the initial and final states are both saturated vapour states and the ideal (isentropic) expansion line runs in the superheated (dry) vapour region all along the expansion. Problems related to the presence of droplets or superheated dry steam in the final expansion state can be avoided or minimized by using the working fluid chosen with this method. Results obtained with real materials are compared with those gained with model (van der Waals) fluids; based on the results obtained with model fluids, erroneous experimental data-sets can be pinpointed. Since most of the known working fluids have optimal expansion routes at low temperatures, presently the method is most suitable to choose working fluids for cryogenic cycles, applied for example for heat recovery during LNG-regasification. Some of the materials, however, can be applied in ranges located at relatively higher temperatures, therefore the method can also be applied in some limited manner for the utilization of other low temperature heat sources (like geothermal or waste heat) as well.

13

Thompson, Philip A., Humberto Craves, G. E. A. Meier, Yoon-Gon Kim, and H. D. Speckmann. "Wave splitting in a fluid of large heat capacity." Journal of Fluid Mechanics 185 (December 1987): 385–414. http://dx.doi.org/10.1017/s0022112087003227.

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The splitting of a single pressure discontinuity into a propagating two-wave system is studied for the case of saturated-liquid expansion (liquid-evaporation wave splitting) and vapour compression (vapour-condensation wave splitting). Experimental results from the Max-Planck-Institut für Strömungsforschung and from Rensselaer Polytechnic Institute show that splitting occurs in test fluids of large molar heat capacity, such as iso-octane (Cv0/R≈ 37). Each of the two forms of splitting results in a single-phase forerunner wave carrying a pressure discontinuity followed by a phase-change wave, also with a pressure discontinuity. The thermodynamic state between the forerunner wave and the phase-change wave is metastable (supersaturated liquid or vapour). The waves are quantitatively described by systems of adiabats, e.g. shock adiabats. It appears that nucleation processes are predominantly homogeneous.In vapour-compression shock-wave splitting, a combined wave (liquefaction shock) splits into discrete forerunner and condensation waves at a triple point, the intersection of a liquefaction shockfront, forerunner shock and condensation discontinuity: such a point occurs just at critical supersaturation (i.e. the Wilson-line state), where condensation is spontaneous and immediate. For shock waves that produce a metastable state of subcritical supersaturation, condensation is delayed, that is, the condensation discontinuity propagates more slowly; for a split-shock system, the condensation discontinuity propagates subsonically. The pressure amplitude of a real split-shock system is much larger than that predicted by an equilibrium model.In liquid-evaporation wave splitting, the forerunner wave is an acoustic expansion wave and the second wave an evaporation wave with a propagation velocity approximately determined by the Chapman-Jouguet condition for deflagration. Such evaporation wavefronts are increasingly distinct as the temperature approaches the critical-point value. The evaporation rates across the wavefront are comparable to those found in vapour explosions.

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WILSON, S. K., S. H. DAVIS, and S. G. BANKOFF. "The unsteady expansion and contraction of a long two-dimensional vapour bubble between superheated or subcooled parallel plates." Journal of Fluid Mechanics 391 (July 25, 1999): 1–27. http://dx.doi.org/10.1017/s0022112099004516.

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In an attempt to model the growth and collapse of a vapour bubble in nucleate boiling this paper investigates the unsteady expansion and contraction of a long two-dimensional vapour bubble confined between superheated or subcooled parallel plates whose motion is driven by mass-transfer effects due to evaporation from the liquid to the vapour and condensation from the vapour to the liquid. It is shown that in the asymptotic limit of strong surface tension (small capillary number) the solution consists of two capillary-statics regions (in which the bubble interface is semicircular at leading order) and two thin films attached to the plates, connected by appropriate transition regions. This generalization of the steady and isothermal problem addressed by Bretherton (1961) has a number of interesting physical and mathematical features. Unlike in Bretherton's problem, the bubble does not translate but can change in size. Furthermore, the thin films are neither spatially nor temporally uniform and may dry out locally, possibly breaking up into disconnected patches of liquid. Furthermore, there is a complicated nonlinear coupling with a delay character between the profiles of the thin films and the overall expansion or contraction of the bubble which means that the velocity with which the bubble expands or contracts is typically not monotonic. This coupling is investigated for three different combinations of thermal boundary conditions and two simple initial thin-film profiles. It is found that when both plates are superheated equally the bubble always expands, and depending on the details of the initial thin-film profiles, this expansion may either continue indefinitely or stop in a finite time. When both plates are subcooled equally the bubble always contracts, and the length of the thin-film region always approaches zero asymptotically. When one plate is superheated and the other subcooled with equal magnitude the bubble may either expand or contract initially, but eventually the bubble always contracts just as in the pure-condensation case.

15

Geisler, A. E., and N. Wenzel. "Impact of the Metal Evaporation Rate in Vacuum Interrupters on Vapor Expansion and Deposition in Vacuum." PLASMA PHYSICS AND TECHNOLOGY 6, no. 2 (2019): 165–69. http://dx.doi.org/10.14311/ppt.2019.2.165.

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The emission of contact material into vacuum after switching operation of a vacuum interrupter is crucial for the metallisation of the ceramic surfaces. This work focuses on the simulation of various regimes of metal vapour pressure using an extended version of an existing DSMC code that now allows the visualisation of the interaction types and locations during the vapour expansion. The model was applied to a typical vacuum interrupter geometry at different current levels between 3 A and 100 kA. The simulations show that in the low current case the likelihood for a particle hitting a ceramic surface can be more than a factor of 5 higher than in the high current case. An explanation of this observation will be given by analysing the interaction history of the respective particles.

16

Horlock, J. H. "Simplified Analyses of Some Vapour Power Cycles." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 210, no. 3 (June 1996): 191–202. http://dx.doi.org/10.1243/pime_proc_1996_210_032_02.

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A range of vapour power cycles is analysed, using the assumption originally made by Schaff that along a turbine expansion line the difference between the (local) enthalpy (h) and the liquid enthalpy at the same pressure ( hL) may remain unchanged (β = h – hL is constant). The thermodynamics of the assumption are critically examined and it is found to be valid only over strictly limited ranges of properties (usually low-pressure levels). However, if such limitations are accepted, the analyses provide understanding of the effects of various key parameters on thermal efficiency, and of measures (such as feed heating, reheat, dual pressure boilers, etc.) that are taken to raise that efficiency.

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Damanik, Jhon Berry Finn, Bambang Admadi Harsujuwono, and Lutfi Suhendra. "Pengaruh Konsentrasi Asam Stearat dan Suhu Gelatinisasi terhadap Karakteristik Komposit Bioplastik Tapioka dan Glukomanan." JURNAL REKAYASA DAN MANAJEMEN AGROINDUSTRI 10, no. 1 (March 28, 2022): 44. http://dx.doi.org/10.24843/jrma.2022.v10.i01.p05.

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This study aims to determine the effect of stearic acid concentration and gelatinization temperature and the interaction of the two treatments on the characteristics of tapioca and glucomannan bioplastic composites, and determine the concentration of stearic acid and gelatinization temperature which can produce bioplastic composites with the best characteristics. This study used a randomized block design with two factors. The first factor is the concentration of stearic acid which consists of 0.2%, 0.4%, 0.6%, 0.8%. The second factor is the gelatinization temperature which consists of 4 temperatures, namely 70±1°C, 75±1°C, 80±1°C, 85±1°C. The variables observed in this study were tensile strength, elongation at break, elasticity, thickness expansion, water vapor transmission rate, biodegradation and functional group analysis. The data were analyzed for diversity and continued with Duncan's Multiple Comparison. The results showed that the concentration of stearic acid and gelatinization temperature had a very significant effect on tensile strength, thickness expansion, water vapor transmission rate and biodegradation. The interaction between treatments had a very significant effect on tensile strength, thickness expansion, water vapor transmission rate and biodegradation and significantly affected elongation at break and elasticity. The best tapioca and glucomannan bioplastic composites used a stearic acid concentration of 0.4% and a gelatinization temperature of 80±1°C which had the characteristics of a tensile strength of 23.86 MPa, elongation at break 8.70%, elasticity 274.40 MPa, thickness expansion 111.52%, water vapour transmission rate 1.05 g/m2.hour, biodegradation rate with 7 days old. Tapioca and glucomannan bioplastic composites contain functional groups of hydroxyl (O-H), alkyne (C?H), aldehyde (C=O), carboxylic acid (C-O), alkene (C-H) and hydroxyl hydrocarbon (CH2)n. Keywords : bioplastic composite, tapioca, glucomannan, stearic acid, gelatinization temperature

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Misra, R. K. "Thermodynamic Performance Evaluation of Multi-Evaporators single Compressor and single Expansion Valve and Liquid Vapour Heat Exchanger in Vapour Compression Refrigeration systems using Thirteen Eco-friendly Refrigerants for Reducing Global Warming and Oz." International Journal of Advance Research and Innovation 2, no. 2 (2014): 139–49. http://dx.doi.org/10.51976/ijari.221421.

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The methods for improving first law and second law efficiency have been considered in this paper by using liquid vapour heat exchanger is investigated in this paper. Detailed energy and exergy analysis of multi-evaporators at different temperatures with single compressor and single expansion valve using liquid vapour heat exchanger vapour compression refrigeration systems have been done in terms of performance parameter for R507a, R125, R134a, R290, R600, R600a, R1234ze, R1234yf, R410a, R407c, R707, R404a and R152a refrigerants. The numerical computations have been carried out for both systems. It was observed that first law and second law efficiency improved by 20% using liquid vapour heat exchanger in the vapour compression refrigeration systems. It was also observed that performance of both systems using R717 is higher but R600 and R152a nearly matching same values under the accuracy of 5% can be used in the above system .But difficulties using R152a, R600, R290 and R600a have flammable problems therefore safety measures are required using these refrigerants. Therefore R134a refrigerant is recommended for practical and commercial applications although it has slightly less thermal performance than R152a which is not widely used refrigerant for domestic and industrial applications

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Mishra, R. S. "Thermodynamic Performance Evaluation of Multi-Evaporators Single Compressor and Single Expansion Valve and Liquid Vapour Heat Exchanger in Vapour Compression Refrigeration Systems using Thirteen Ecofriendly Refrigerants for Reducing Global Warming and Ozo." International Journal of Advance Research and Innovation 1, no. 3 (2013): 107–17. http://dx.doi.org/10.51976/ijari.131315.

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The methods for improving first law and second law efficiency have been considered in this paper by using liquid vapour heat exchanger is investigated in this paper. Detailed energy and exergy analysis of multi-evaporators at different temperatures with single compressor and single expansion valve using liquid vapour heat exchanger vapour compression refrigeration systems have been done in terms of performance parameter for R507a, R125, R134a, R290, R600, R600a, R1234ze, R1234yf, R410a, R407c, R707, R404a and R152a refrigerants. The numerical computations have been carried out for both systems. It was observed that first law and second law efficiency improved by 20% using liquid vapour heat exchanger in the vapour compression refrigeration systems. It was also observed that performance of both systems using R717 is higher but R600 and R152a nearly matching same values under the accuracy of 5% can be used in the above system .But difficulties using R152a, R600, R290 and R600a have flammable problems therefore safety measures are required using these refrigerants. Therefore R134a refrigerant is recommended for practical and commercial applications although it has slightly less thermal performance than R152a which is not widely used refrigerant for domestic and industrial applications

20

Belaustegi, Y., M. J. Citores, and L. A. Fernández. "Automation of Vapour Pressure Osmometry measurements." Journal of Automatic Chemistry 13, no. 5 (1991): 181–85. http://dx.doi.org/10.1155/s1463924691000329.

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A program has been developed for the control of Vapour Pressure Osmometry (VPO) measurements. The output signal of a Vapour Pressure Osmometer is read by an A/D converter card installed in one of the expansion slots of a PC microcomputer. The stability of the measurements is checked by analysing the first derivative of the smoothed signals, which is calculated in real time. Sets of repeated measurements are carried out under the supervision of a computer program as a check for their reproducibility. When the set is ended the program calculates the average and its standard deviation.The program is particularly valuable for evaluating VPO measurements for solution equilibria studies. This interfacing strategy may be applied to any kind of technique in which the time stability of the signals is the basis for defining measurement stability. The automated VPO has other advantages, including low cost and time saving.

21

Richardson, R. N., and J. S. Butterworth. "A Novel Vapour-Compression Refrigeration Circuit Employing a Computer-Controlled Expansion Valve." International Journal of Mechanical Engineering Education 23, no. 1 (January 1995): 1–7. http://dx.doi.org/10.1177/030641909502300103.

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Igobo, Opubo N., and Philip A. Davies. "Review of low-temperature vapour power cycle engines with quasi-isothermal expansion." Energy 70 (June 2014): 22–34. http://dx.doi.org/10.1016/j.energy.2014.03.123.

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You, Qinglong, Jinzhong Min, Shichang Kang, and Nick Pepin. "Poleward expansion of the tropical belt derived from upper tropospheric water vapour." International Journal of Climatology 35, no. 9 (August 12, 2014): 2237–42. http://dx.doi.org/10.1002/joc.4125.

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Miniotaitė, Rūta, and Vytautas Stankevičius. "THE DURABILITY OF PAINTS ON SAND-LIME BRICK WALLS CONSIDERING WATER SORPTION AND VAPOUR PERMEABILITY IN A TWO-LAYER SYSTEM." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 9, no. 2 (June 30, 2003): 110–14. http://dx.doi.org/10.3846/13923730.2003.10531313.

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It is assumed that the proposed coatings are suitable for finishing selected surfaces. However, our research indicated that the provided specific physical-mechanical properties of the coatings may change in a new combination of “coating—substrate”. It was found while analysing the results of grouped paints investigations that specific nature of vapour permeability and absorption, the effect of opposition thereof, the expansion of destruction and expression of its symptoms were characteristic of each group. Physical-mechanical properties of constructions substrate and finishing layer can supplement one another or, quite contrary, stimulate destruction. Analytical review of the influence made by two parameters (vapour resistance and rain penetration) upon durability of paints of various structural origins indicated that usually rain-penetration influence was higher. However, while evaluating humidity of complete finished layer (paint + substrate) as a process: “rain penetration—moisture migration from the inside (drying)—vapour isolation of the coating as a barrier to drying process”, in case of film-forming paints the influence of vapour resistance is high too.

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Smith, I. K., and R. Pitanga Marques da Silva. "Development of the Trilateral Flash Cycle System Part 2: Increasing Power Output with Working Fluid Mixtures." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 208, no. 2 (May 1994): 135–44. http://dx.doi.org/10.1243/pime_proc_1994_208_022_02.

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The trilateral flash cycle system is a proposed means of power recovery from single-phase low-grade heat sources. Its feasibility depends on the efficient adiabatic expansion of light hydrocarbons from the saturated liquid phase into the two-phase region. Such a process is performed most effectively with a Lysholm twin-screw expander when the exhausted vapour is wet. At higher temperatures, when multi-stage expansion is required, working fluids may be found which complete the process as dry saturated vapour. It is shown that at condensing temperatures of 0–50°C, this is possible with a mixture of n-pentane and 2,2–dimethylpropane (neopentane) for fluid inlet temperatures in the 150–180 °C range. A radial inflow turbine may then be used in place of a screw for the last stage. With such an arrangement, expander adiabatic efficiencies of up to 85 per cent have been predicted for power outputs in excess of 5 MW. The method of fluid property estimation is described and its accuracy confirmed by experiment.

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Hansen, H. C. B., and R. M. Taylor. "The use of glycerol intercalates in the exchange of CO32− with SO42−, NO3− or Cl− in pyroaurite-type compounds." Clay Minerals 26, no. 3 (September 1991): 311–27. http://dx.doi.org/10.1180/claymin.1991.026.3.02.

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AbstractStrongly held carbonates anions in the interlayer region of pyroaurite-type compounds, [MlII1−xM2IIIx(OH)2]x+[(CO3)x/2yH2O]x− (x = 0·15−0·44), can be relatively easily exchanged by other anions such as NO3−, Cl− or SO42− dissolved in heated glycerol. Some Fe(III) of pyroaurite is reduced to Fe(II) by the glycerol treatment. If pyroaurite is treated with glycerol in the absence of dissolved anions or with glycerol vapour at 120°C, glycerol becomes intercalated in the interlayers. In all examples the interlayer CO32− is partially or completely lost as CO2. In aqueous salt solutions a glycerol intercalated form allows other anions to substitute in the interlayer. Expansion in the c-axis direction following glycerol treatment depends on (1) the method of glycerol treatment, (2) the trivalent metal in the octahedral sheet, and (3) the interlayer anions. Heated glycerol causes a different expansion to that produced by its vapour phase at 120°C. The variation in d(003) follows the series: hydrotalcitevap. > pyroauritevap. > hydrotalciteliquid > pyroauriteliquid > SO42−-pyroauritevap. > SO42−-hydrotalcitevap., where liquid refers to glycerol used at 160–180°C and vap. refers to glycerol vapour at 120°C Carbonate-free, glycerol-intercalated pyroaurite compounds may serve as re-usable anion absorbers. Glycerol intercalates of pyroaurite-type compounds may also be useful to study and identify stacking sequences and interlayer compositions in these minerals.

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Zhalehrajabi, Ehsan, and Nejat Rahmanian. "Nucleation and Condensation Modeling of Metal Vapor in Laval Nozzle." Advanced Materials Research 925 (April 2014): 185–89. http://dx.doi.org/10.4028/www.scientific.net/amr.925.185.

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Nucleation and condensation of mercury vapor has been investigated in various divergent angle and operating condition. Divergent angle has a great effect on droplet size at the end of nozzle. Influence of operating condition such as pressure and temperature on the size of droplet has been investigated. A one-dimensional mathematical model based on classical nucleation and growth has been developed to calculate the nucleation and condensation of mercury vapor. A mercury vapour turbine has been used in conjunction with a steam turbine for generating electricity. The mercury cycle offers an efficiency increase compared to a steam-only cycle because energy can be injected into the Rankine Cycle at higher temperature. The target of modeling is predicting the droplet size of mercury nanoparticles during rapid expansion. The results are verified by accurate experimental data available in the literature. The governing equations were solved using Runge-Kutta third-order numerical method in MATLAB software.

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Yakush, S. E., N. S. Sivakov, V. I. Melikhov, and O. I. Melikhov. "Numerical modelling of melt droplet interaction with water." Journal of Physics: Conference Series 2057, no. 1 (October 1, 2021): 012057. http://dx.doi.org/10.1088/1742-6596/2057/1/012057.

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Abstract A collapse of the vapour film separating a hot melt droplet from the surrounding water due to sudden ambient pressure rise is considered. The pressure peak causes a direct contact between water and melt, leading to significant disturbances of the melt droplet surface. Results of numerical simulations performed by the VOF method are presented. Parametric analysis of the interaction process is performed for a molten tin droplet with initial temperature of 950 K, immersed in subcooled water having the temperature of 353 K. The interaction is initiated by sudden rise of the ambient pressure to as much as 8 MPa, imitating the arrival of a thermal detonation wave, with its gradual decrease towards the initial pressure of 0.1 MPa. Simulations reveal the collapse of the vapour film, impingement of water on the droplet surface, and subsequent expansion of vapour due to rapid water evaporation. Significant disturbances of the melt droplet surface are obtained, and implications for the steam explosion problem are discussed.

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R Hariharan et al. "Hardened Enhancement Investigation of Al-Zr-N Coating by EBM Technique: A review." Proceeding International Conference on Science and Engineering 11, no. 1 (February 18, 2023): 122–31. http://dx.doi.org/10.52783/cienceng.v11i1.106.

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The purpose of this research is to examine the Al-Zr-N coating applied to the E19 steel alloy by physical vapour deposition using an electron beam. The physical vapour deposition processes used to create layered [Al-Zr-N] coatings and the structures, wear resistances, and corrosion behaviours of these materials. In order to examine the coating structures, surface roughness, micro-hardness, micro-abrasion, and pin on disc were used. One of the residual stress elements that can lead to failure mechanisms for suitable coatings is thermal stress. The mechanical characteristics of the coating, including its deposition temperature, young's modulus, thermal expansion coefficient, and substrate and coating thickness, were investigated using a validated computational simulation in this paper.

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Devi, M. Jyostna, Earl W. Taliercio, and Thomas R. Sinclair. "Leaf expansion of soybean subjected to high and low atmospheric vapour pressure deficits." Journal of Experimental Botany 66, no. 7 (January 24, 2015): 1845–50. http://dx.doi.org/10.1093/jxb/eru520.

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BARTON, N. G. "AN EVAPORATION HEAT ENGINE AND CONDENSATION HEAT PUMP." ANZIAM Journal 49, no. 4 (April 2008): 503–24. http://dx.doi.org/10.1017/s1446181108000035.

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AbstractThis paper presents a thermodynamic model for a heat engine based on evaporative cooling of unsaturated air at reduced pressure. Also analysed is a related heat pump based on condensation of water vapour in moist air at reduced pressure. These devices operate as two-stroke reciprocating engines, which are their simplest possible embodiments. The mathematical models for the two devices are based on conservation of mass for both air and water vapour, ideal gas laws, constant specific heats, and, as appropriate, either constant entropy processes or cooling/heating by evaporation/condensation. Both models take the form of coupled algebraic systems in six variables, which require numerical solution for certain stages of the cycle. The specific work output of the heat engine increases as the inlet air becomes hotter and as the expansion ratio of the engine increases. The engine provides evaporative cooling of air from inlet to outlet. The heat pump has a good coefficient of performance, which decreases as the expansion ratio increases. The heat pump also has the effect of drying the air from inlet to outlet, producing distilled water as a by-product.

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Ganorkar, Atul. "Performance Evaluation of Water Cooled Condenser of Air Conditioner Working on VCRS." INTERANTIONAL JOURNAL OF SCIENTIFIC RESEARCH IN ENGINEERING AND MANAGEMENT 08, no. 05 (May 15, 2024): 1–5. http://dx.doi.org/10.55041/ijsrem34032.

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VCRS commonly known as (Vapour Compression Refrigeration System) is widely adopted method for air conditioning of buildings, in pharmaceutical industry for storage of medicine, in hospitals, automobiles etc. There are several methods for increasing the efficiency% (COP) of an VCRS cycle. Some of the modification can be done in Compressor, Condenser, Evaporator, and in Refrigerant . In this experiment, we adopted method of Subcooling to reduce Compressor work. This study investigates the implementation of subcooling in the condenser of a Vapour Compression Refrigeration System (VCRS) to enhance its efficiency and reduce power consumption. The traditional condenser design is modified by submerging it in a water tank, allowing for subcooling of the refrigerant. The subcooling process involves lowering the temperature of the refrigerant below its saturation temperature, which improves the system’s Coefficient of Performance (COP) by increasing the density of the refrigerant entering the expansion valve. This modification aims to optimize the heat rejection process and enhance the overall performance of the refrigeration system .Experimental result demonstrate a significant reduction in power consumption and an improvement in COP, highlighting the effectiveness of the condenser subcooling method in enhancing the efficiency of VCRS. Keywords : Compressor, Condenser, Expansion Valve, Evaporator.

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Kowalczyk, Tomasz, Paweł Ziółkowski, and Janusz Badur. "Exergy analysis of the Szewalski cycle with a waste heat recovery system." Archives of Thermodynamics 36, no. 3 (September 1, 2015): 25–48. http://dx.doi.org/10.1515/aoter-2015-0020.

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Abstract The conversion of a waste heat energy to electricity is now becoming one of the key points to improve the energy efficiency in a process engineering. However, large losses of a low-temperature thermal energy are also present in power engineering. One of such sources of waste heat in power plants are exhaust gases at the outlet of boilers. Through usage of a waste heat regeneration system it is possible to attain a heat rate of approximately 200 MWth, under about 90 °C, for a supercritical power block of 900 MWel fuelled by a lignite. In the article, we propose to use the waste heat to improve thermal efficiency of the Szewalski binary vapour cycle. The Szewalski binary vapour cycle provides steam as the working fluid in a high temperature part of the cycle, while another fluid – organic working fluid – as the working substance substituting conventional steam over the temperature range represented by the low pressure steam expansion. In order to define in detail the efficiency of energy conversion at various stages of the proposed cycle the exergy analysis was performed. The steam cycle for reference conditions, the Szewalski binary vapour cycle as well as the Szewalski hierarchic vapour cycle cooperating with a system of waste heat recovery have been comprised.

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Sairamakrishna, B., T. Gopala Rao, and N. Rama Krishna. "Cop Enhancement of Vapour Compression Refrigeration System." Indian Journal of Production and Thermal Engineering 1, no. 2 (June 10, 2021): 1–6. http://dx.doi.org/10.35940/ijpte.b2004.061221.

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This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).

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B, Sairamakrishna, T. Gopala Rao, and Rama Krishna, N. "Cop Enhancement of Vapour Compression Refrigeration System." Indian Journal of Production and Thermal Engineering 1, no. 2 (June 10, 2021): 1–6. http://dx.doi.org/10.35940/ijpte.b2004.06122.

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This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).

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Sairamakrishna, B., T. Gopala Rao, and N. Rama Krishna. "Cop Enhancement of Vapour Compression Refrigeration System." Indian Journal of Production and Thermal Engineering 1, no. 2 (June 10, 2021): 1–6. http://dx.doi.org/10.54105/ijpte.b2004.061221.

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This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).

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Zabet, Ion, and Gratiela Maria Tarlea. "Mathematical Simulation of the Thermodynamic Processes Associated with the Vapour-Injected Scroll Compressor." E3S Web of Conferences 111 (2019): 06057. http://dx.doi.org/10.1051/e3sconf/201911106057.

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Both the major energetic crisis and the global warming, which influence the worldwide economy and the future of the society, determine the development of energetic and ecological performances of both the refrigeration equipment and air conditioning systems. Thus, there is a worldwide supported effort made in order to decrease the carbon dioxide emissions resulted from the burning of fossil fuels and the other greenhouse effect gas emissions. This article presents a refrigeration system design model using a vapour injection scroll compressor and tube in tube evaporators working with refrigerant R407C. The refrigerant circuit comprises of a main evaporator, a secondary evaporator (for the injection process), scroll compressor, condenser and five expansion valves. Furthermore it uses R407C as refrigerant. The secondary refrigerant for both the main and the secondary evaporator is a 50% concentration solution of propylene-glycol and water. Secondary circuit comprises of a pump, an electric boiler, an expansion vessel and a by-pass circuit made of many stop valves. The condenser is cooled with mains water.

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Cheng, Ruishan, Wensu Chen, Hong Hao, and Jingde Li. "Dynamic response of road tunnel subjected to internal Boiling liquid expansion vapour explosion (BLEVE)." Tunnelling and Underground Space Technology 123 (May 2022): 104363. http://dx.doi.org/10.1016/j.tust.2022.104363.

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Jurski, K., and E. Géhin. "Heterogeneous condensation process in an air water vapour expansion through a nozzle––experimental aspect." International Journal of Multiphase Flow 29, no. 7 (July 2003): 1137–52. http://dx.doi.org/10.1016/s0301-9322(03)00083-1.

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Singh, Jagdev, Nirmal Singh, and J. K. Sharma. "MODELING AND SIMULATION FOR INTELLIGENT CONTROL OF EXPANSION VALVE IN VAPOUR COMPRESSION REFRIGERATION SYSTEM." Cybernetics and Systems 38, no. 4 (May 2007): 411–27. http://dx.doi.org/10.1080/01969720701291247.

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Prasetyo, Totok, Mochamad Denny Surindra, Wahyu Caesarendra, Taufik, Adam Glowacz, Muhammad Irfan, and Witold Glowacz. "Influence of Superheated Vapour in Organic Rankine Cycles with Working Fluid R123 Utilizing Low-Temperature Geothermal Resources." Symmetry 12, no. 9 (September 7, 2020): 1463. http://dx.doi.org/10.3390/sym12091463.

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An organic Rankine cycle (ORC) system with R123 working fluid has been utilised for generating electricity from low-temperature geothermal resources. The degree of superheated vapour warrants attention to be studied further. This is because the degree of superheated vapour is the last point to absorb heat energy from geothermal heat sources and influence the amount of expansion power produced by the expander. Therefore, achieving high ORC system efficiency requires a parameter of superheated vapour degree. This paper presents an experimental study on a binary cycle, applying R123 as the working fluid, to investigate the effect of variation in superheated vapour degree on the ORC efficiency. Geothermal heat sources were simulated with conduction oil as an external heat source to provide input heat to the ORC system. The temperature high inlet (TH in) evaporator was designed to remain at 120 °C during the experiment, while mass flow rate was adjusted to make superheated vapour variations, namely set at 278, 280, 282, 284, and 286 K. Furthermore, the effect was observed on heat transfer inlet, pinch, heat transfer coefficient, expander work output, isentropic efficiency, expander shaft power, power generation, thermal efficiency, and ORC efficiency. The experimental results showed that the mass flow rate nearly remained unchanged at different degrees of superheated vapour. The ranges of heat transfer inlet, pinch temperature, and heat transfer coefficient were 25.34–27.89 kJ/kg, 9.35–4.08 °C, 200.62–232.54 W/m2·K, respectively. In conclusion, ORC system efficiency can be triggered by various parameters, including the temperature on the exit side of the evaporator. The superheated vapour of R123 working fluid to higher temperatures has caused a decrease in ORC system efficiency due to the decrease in heat transfer inlets, although theoretically, the work total increased. Further investigation has found that the magnitude of the mass flow rate affects the behaviour of the components of the ORC system.

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Traverso, Alberto, Federico Reggio, Paolo Silvestri, Sergio Rizzo, Geoff Engelbrecht, and Alexandros Chasoglou. "Two-phase flow expansion: development of an innovative test-rig for flow characterisation and CFD validation." E3S Web of Conferences 113 (2019): 03017. http://dx.doi.org/10.1051/e3sconf/201911303017.

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The aim of this work is to describe the design of an innovative test rig for investigating the expansion of saturated fluids in the two-phase region. The experimental test rig was thought up and built by TPG of the University of Genoa. It will be equipped by probes and some optical accesses that permit high speed video recording and laser measurements. It will be useful for the study of the quality ratio, vapour and liquid droplet thermodynamic properties and their speed.

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Bakhtar, F., H. Mashmoushy, and O. C. Jadayel. "On the performance of a cascade of turbine rotor tip section blading in wet steam Part 2: Surface pressure distributions." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 211, no. 7 (July 1, 1997): 531–40. http://dx.doi.org/10.1243/0954406971521917.

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In the course of expansion in turbines steam nucleates to become a two-phase mixture, the liquid consisting of a very large number of extremely small droplets carried by the vapour. Formation and subsequent behaviour of the liquid lowers the performance of turbine wet stages. To produce turbine nucleating and wet flow conditions realistically requires a supply of supercooled steam which can be achieved under blow-down conditions by the equipment employed. To obtain wet steam, the supercooled vapour generated is passed through a venturi before admission to the cascade. To evaluate the influence of droplet size two separate Venturis have been used in the investigation. The performance of a cascade of rotor tip section blading in wet steam has been studied. This paper is the second of a set and describes the results of the surface pressure measurements.

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Vamsi, T., Sk Nayab Rasool, V. Ratna Ramesh, K. Hemanth, J. V. S. S. Neeraj Kumar, and S. Venkateswara Rao. "A Review on Experimental Analysis on Hybrid Vapour Compression Refrigeration System." International Journal for Research in Applied Science and Engineering Technology 10, no. 9 (September 30, 2022): 572–76. http://dx.doi.org/10.22214/ijraset.2022.46685.

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Abstract: A vapor-compression refrigeration system is a system that uses liquid refrigerant in a closed system which circulates the refrigerant through four stages in which it is alternately compressed and expanded, changing it from liquid to vapor. As this change happens, heat is either absorbed or expelled by the system, resulting in a change in temperature of the surrounding air that is passing over the unit's components. Nearly all of the refrigeration systems we use today use this cycle to accomplish cooling. VCRS system is made up of four main components: the evaporator, condenser, compressor and expansion valve. The evaporator and condenser are both a series of coils that are designed to create more surface area for the refrigerant to react with. Meanwhile, the compressor and expansion valve are mechanical units that control the amount of pressure and temperature change that occurs between the two stages. It was named after Jean Charles Athanase Peltier, the physicist who discovered the effect in 1834. Peltier discovered that when current is made to flow through a circuit consisting of two different types of conductors, a heating or cooling effect is observed at the junctions between the two materials. This change in temperature at the junction is called the Peltier effect. When electric current is passed through a circuit consisting of two different conductors, a cooling effect is observed in one junction whereas another junction experiences a rise in temperature. This change in temperatures at the junctions is called the Peltier effect. The effect is found to be even stronger when two different semiconductors are used in place of conductors in the circuit. In this journal Two methods of refrigeration work together to get a good coefficient of performance (COP). The both vapour compression refrigeration method which good in control the inside temperature and peltier effect by combined together in a single setup. The heat generated from the two dissimilar semiconductors are used to change the complete phase transformation of the refrigerant system before entering into the compressor. The combined system we call it as hybrid experimental system. The COP of thermoelectric system in combined with VCRS is increased by proper heat dissipation, from hot side of the peltier units and these heat fluxes utilized by VCRS for its own benefit.

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Read, MG, IK Smith, and N. Stosic. "Optimisation of power generation cycles using saturated liquid expansion to maximise heat recovery." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 231, no. 1 (December 11, 2016): 57–69. http://dx.doi.org/10.1177/0954408916679202.

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The use of two-phase screw expanders in power generation cycles can achieve an increase in the utilisation of available energy from a low-temperature heat source when compared with more conventional single-phase turbines. The efficiency of screw expander machines is sensitive to expansion volume ratio, which, for given inlet and discharge pressures, increases as the expander inlet vapour dryness fraction decreases. For single-stage screw machines with low inlet dryness, this can lead to underexpansion of the working fluid and low isentropic efficiency. The cycle efficiency can potentially be improved by using a two-stage expander, consisting of a machine for low-pressure expansion and a smaller high-pressure machine connected in series. By expanding the working fluid over two stages, the built-in volume ratios of the two machines can be selected to provide a better match with the overall expansion process, thereby increasing the efficiency. The mass flow rate though both stages must be matched, and the compromise between increasing efficiency and maximising power output must also be considered. This study is based on the use of a rigorous thermodynamic screw machine model to compare the performance of single- and two-stage expanders. The model allows optimisation of the required intermediate pressure in the two-stage expander, along with the built-in volume ratio of both screw machine stages. The results allow specification of a two-stage machine, using either two screw machines or a combination of high-pressure screw and low-pressure turbine, in order to achieve maximum efficiency for a particular power output. For the low-temperature heat recovery application considered in this paper, the trilateral flash cycle using a two-stage expander and the Smith cycle using a high-pressure screw and low-pressure turbine are both predicted to achieve a similar overall conversion efficiency to that of a conventional saturated vapour organic Rankine cycle.

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Morin, Richard, Ghfran Al Chami, Richard Gagné, and Benoit Bissonnette. "Design Considerations and Innovative Approach for Restoration of Historic Landmarks in Old Montreal." MATEC Web of Conferences 199 (2018): 07003. http://dx.doi.org/10.1051/matecconf/201819907003.

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Restoration of some streets in Old Montreal is achieved using granite pavers bonded with a mortar bed to a concrete slab. The technique was originally used for the pavement of St-Paul Street with stone bricks back in the 1800's. A similar approach is being used in 2016 to renovate the very same street, except for the materials used in casting the foundation slab. In order to space out the expansion joints and prevent drying shrinkage cracking, fibre reinforcement and an expansive component are incorporated in the concrete. The concept was successfully used in bridge deck rehabilitation projects such as Girouard Overpass deck overlay. The basic principle of this approach is to generate a chemical expansion in the concrete (200 to 300 gm/m) using an expansive component, and to restrain the generated expansion through the combined action of ordinary peripheral steel reinforcement in the slab and steel fibre reinforcement in the concrete. The objective is to mitigate shrinkage stresses by keeping the strain balance as low as possible and allowing the concrete additional time to develop sufficient tensile strength, such that the stresses induced in the concrete slabs will remain lower than the concrete tensile strength.Restraint of expansion by the steel fibres and the peripheral reinforcement induces an initial compressive stress in the concrete slab. A part of this stress is used to compensate for the drying shrinkage, whereas the remaining part (if any) is used to resist incidental restrained deformation (e.g. thermal strains) cracking. Concrete mixture proportioning, placement, and curing need to be optimized in order to achieve enough expansion to adequately control cracking due to restrained shrinkage. After proper moist curing of the slab, the pavers are bonded to its top surface using a latex-modified mortar (latex to cement ratio of about 11% by mass). The latex-modified mortar used as a levelling bed underneath the pavers has a low vapour permeability that partially seals the concrete surface and further contributes to minimize drying shrinkage cracking. Since 2011, various historic landmarks in the City of Montreal have been restored using concrete containing an expansive component. To this date, monitoring and performance reports have showed that the chemical prestress approach is quite effective in decreasing shrinkage cracking in paved street foundations, thereby allowing the placement of longer slabs with significantly fewer expansion joints.

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Kartashov, I. N., and A. A. Samokhin. "Stability of the front of laser evaporation of metals under conditions of limited vapour expansion." Quantum Electronics 33, no. 5 (May 31, 2003): 435–40. http://dx.doi.org/10.1070/qe2003v033n05abeh002430.

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Sutthivirode, Kittiwoot, and Tongchana Thongtip. "Experimental investigation of vapour compression chiller based on transient cooling performance influenced by expansion devices." Case Studies in Thermal Engineering 21 (October 2020): 100669. http://dx.doi.org/10.1016/j.csite.2020.100669.

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Gomes, A., A. Aubreton, J. J. Gonzalez, and S. Vacquié. "Experimental and theoretical study of the expansion of a metallic vapour plasma produced by laser." Journal of Physics D: Applied Physics 37, no. 5 (February 11, 2004): 689–96. http://dx.doi.org/10.1088/0022-3727/37/5/007.

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Bakhtar, F., M. Ebrahimi, and B. O. Bamkole. "On the Performance of a Cascade of Turbine Rotor Tip Section Blading in Nucleating Steam: Part 2: Wake Traverses." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 209, no. 3 (May 1995): 169–77. http://dx.doi.org/10.1243/pime_proc_1995_209_140_02.

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During the course of expansion of steam in turbines the fluid first supercools and then nucleates to become a two-phase mixture. To reproduce turbine two-phase flow conditions requires a supply of supercooled vapour which can be achieved under blow-down conditions by the equipment employed. This paper is the second of a set describing an investigation into the performance of a cascade of rotor tip section profiles in nucleating steam and presents the results of the wake traverses and droplet measurements.

Journal articles on the topic 'Vapour expansion'

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