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140 articles for “vaporization”
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Vapor Compression Refrigeration System
Abstract: Refrigeration has been achieved in a variety of methods throughout history, but due to their efficiency anddurability, vapor-compression refrigeration systems (VCRS) have become the favored option. A vapor-compression refrigeration system, in essence, is a system that uses liquid refrigerant in a closed systemthat circulates it through four stages of compression and expansion, transforming it from liquid to vapor.As a result of this change, heat is either absorbed or ejected by …
Published in Journal of Refrigeration, Air conditioning, Heating and ventilation · Vol. 8, Issue 3, 2021 · pp. 30–33 Read article
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Evaluation and Optimization of an Aqua-Ammonia Vapor-Absorption Refrigeration System
Abstract: The process parameters of ammonia-water absorption system were optimized in terms of temperatures of generator and condenser and heat ratios of generator-to-condenser and generator-to-absorber. The iteration method was used to get the variation in generator and condenser temperatures with coefficient of performance (COP) for the fixed evaporator temperature. The sizing of generator, absorber and condenser was found from the variation of heat ratios of generator-to-condenser and generator-to-absorber for the fixed …
Published in Journal of Refrigeration, Air conditioning, Heating and ventilation · Vol. 1, Issue 1, 2014 · pp. 9–17 Read article
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Dynamic Simulation of Load-Responsive Vapor Compression Refrigeration Systems
Abstract: Because of their dependable operation and effectiveness, vapor compression refrigeration systems, or vapor compression refrigeration (VCRS), have become popular in commercial, industrial, and residential settings. However, under different thermal loads, classic vapor compression refrigeration (VCR) systems may perform less well in that they are usually built for steady-state conditions and run at consistent speeds. In order to improve a load-responsive VCR system’s flexibility, energy efficiency, and response to changing cooling …
Published in Journal of Refrigeration, Air conditioning, Heating and ventilation · Vol. 12, Issue 2, 2025 · pp. 32–37 Read article
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Sustainable Innovations in Vapor Compression Systems: A Review of Heat Recovery and Environmental Performance
Abstract: Vapor compression refrigeration systems are widely used in residential, commercial, and industrial sectors, contributing significantly to global energy consumption and greenhouse gas emissions. This review explores sustainable innovations in vapor compression systems, focusing on waste heat recovery techniques and their impact on environmental performance. Key advancements include the integration of heat exchangers, ejector systems, and hybrid configurations that enhance energy efficiency while reducing refrigerant load and emissions. With a focus …
Published in Journal of Thermal Engineering and Applications · Vol. 13, Issue 1, 2026 · pp. 16–21 Read article
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Diesel Adulteration Detection Using Gaseous Vapor Emission
Abstract: Diesel adulteration is the illegal or unauthorized introduction of foreign substances into pure diesel,causing the product to not conform to the requirements and specifications for use in the Oil and GasIndustry. Current methods to detect diesel adulteration require chemical laboratory experiments tomeasure parameters such as density, API gravity, viscosity, flash point, and evaporation point. Thesemethods require specialized, expensive equipment and cannot be utilized be quickly and readilyemployed at point of …
Published in Journal of Petroleum Engineering & Technology · Vol. 11, Issue 1, 2021 · pp. 69–76 Read article
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Evaluation of Coefficient of Performance of Water– Carrol Vapor Absorption Refrigeration System Using Artificial Neural Network approach
Abstract: Normal 0 false false false EN-US X-NONE X-NONE The aim of this work is to apply expert system methods, like artificial neural network (ANN), for evaluating the coefficient of performance (COP) of water-carrol (lithium bromide-ethylene glycol)-based vapor absorption refrigeration system. Theoretical performance analysis of vapor absorption refrigeration system is too complex since very tedious second-order mathematical differential equations are used. In order to simplify this complex process, artificial neural networks …
Published in Trends in Mechanical Engineering & Technology · Vol. 2, Issue 3, 2012 · pp. 29–37 Read article
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Gas Sensors Fabricated using Carbon Powder Derived from Dried Banana Peels Waste to detect Methanol, Ethanol, Acetone Vapors and Carbon Dioxide Gas
Abstract: Low cost and environmentally friendly activated carbon powder was synthesized using waste banana peels. Phosphoric acid was utilized as activation agent. Doctor blade method was employed to fabricate films of activated carbon on conductive or nonconductive glass substrates. Films were subsequently annealed at 70 0C for 30 minutes in air. According to XRD patterns, single phase of activated carbon was crystallized in thin film form. Carbon prepared from banana peels …
Published in Journal of Materials & Metallurgical Engineering · Vol. 15, Issue 3, 2025 · pp. 14–25 Read article
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Performance Assessment of External Source-Driven Binary Vapor Cycles with Ammonia-Water and Trans-Critical CO2: The Impact of Reheating and Pressure Variations
Abstract: This study examines the thermodynamic performance of binary vapor cycles, specifically analysing two working fluid combinations: ammonia-water mixtures and trans-critical carbon dioxide (CO2). The study aims to evaluate their efficiency, applicability, and potential for improving energy conversion systems in various thermal applications. The analysis investigates how incorporating reheating processes and adjusting operating pressures impact system performance. These two parameters play a critical role in enhancing cycle efficiency and maximizing energy …
Published in Journal of Thermal Engineering and Applications · Vol. 12, Issue 2, 2025 · pp. 42–49 Read article
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Effects of Plasticizers on Structures of Chemical Functional Groups, Morphologies, Water Vapor Permeability, and Thermal Properties of HPMC/BW Biopolymer Films
Abstract: Food preservation is one of the fields that many researchers are interested in, especially in the epidemic period like COVID-19 today. The better food or agricultural products are preserved for a long time, the more it ensures social stability for state management related to food security for people. This paper introduces one kind of biopolymer films with investigation on effect of plasticizers to its characteristics. In order to produce biopolymers, …
Published in Journal of Polymer & Composites · Vol. 9, Issue 2, 2021 · pp. 10–20 Read article
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A Compact Review on Physical Vapor Deposition Techniques of Thin Films
Abstract: The effectiveness and performance of a material is greatly influenced by its surface properties. It is possible to manipulate and alter these surface characteristics to satisfy the particular characteristics for better results. One way of modifying these properties is by coating that particular surface with thin film. There exist wide number of methodologies for coating a surface or depositing thin films over it. These techniques can be categorized either as …
Published in Journal of Thin Films, Coating Science Technology & Application · Vol. 6, Issue 2, 2019 · pp. 9–17 Read article
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Experimental Investigation on Performance of Vapor Compression Refrigeration System using Nanorefrigerant (R134a+Al2O3) with/without Evaporative Condenser
Abstract: In traditional refrigeration system the main focus of researchers is always to improve its performance by reducing work of compression and enhancing the heat transfer rate in different heat exchangers and this can be achieved by adopting suitable technique. In this research work experiment is carried out on vapor compression refrigeration test rig using nanorefrigerant of R134a as base refrigerant and nanoparticles of aluminium oxide Al2O3 in different concentration so …
Published in Journal of Refrigeration, Air conditioning, Heating and ventilation · Vol. 7, Issue 3, 2020 · pp. 1–8 Read article
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Enhancement of Gas Sensitivity of Composites of Carbon Derived from Rubber Tree and SnO2 to Detect Ethanol Vapor at Room Temperature
Abstract: Films of composites of activated carbon powder prepared from saw dust derived from core of rubber tree (Hevea Brasiliensis) and tin oxide (SnO2) were fabricated using the doctor blade method. Carbon powder was activated using phosphoric acid at 500°C for 45 minutes. The weight ratio carbon/SnO2 varied from 0 to 12% in steps of 2. The structural, optical and morphological properties of films were investigated using XRD patterns, UV-visible spectrums …
Published in Journal of Thin Films, Coating Science Technology & Application · Vol. 12, Issue 2, 2025 · pp. 31–44 Read article
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Energetic and Exergetic Investigation on Vapor Compression Refrigeration System Using Ag₂O-R134a Nanofluid as Refrigerant
Abstract: This paper experimentally explored energetic and exergetic performance investigation of VCR System using Ag₂O-R134a Nanofluid as Refrigerant. The integration of silver oxide (Ag₂O) nanoparticles within polymer and composite materials offers promising avenues for enhancing the thermal and physical properties of advanced systems. The energetic and exergetic performance study of VCR were investigated with test parameters including compressor power consumption, cooling capacity, coefficient of performance (COP), discharge temperature, irreversibility in the …
Published in Journal of Polymer & Composites · Vol. 14, Issue 1, 2026 · pp. 279–287 Read article
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Development of a Heat Actuator Using Liquid-Vapor Phase Change of R134a
Abstract: AbstractLarge volume changes can be produced by liquid-vapor phase change of working fluids which can be used in actuators as the driving power source. The temperature range of working of such actuators depends on the characteristics of the phase change working fluid. In this paper we discuss the concept and design of a heat actuator which uses liquid-vapor phase change of its working fluid for actuation of a piston. The …
Published in Journal of Thermal Engineering and Applications · Vol. 6, Issue 1, 2019 · pp. 1–4 Read article
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Estimation of PVT Properties and Vapor Pressure of CHON Based Extractants for Nuclear Solvent Extraction
Abstract: CHON amides like N, N′-Di hexyl octanamide (DHOA) and N, N′-Di octyl hexanamide (DOHA) have been identified as the alternate extractants to TBP for nuclear solvent extraction. Critical properties of these amidic solvents are needed for the estimation of various physical properties. Currently, there is little information in the literature about critical properties for these solvents. For these two extractants, critical properties and boiling point were estimated using group contribution …
Published in Journal of Nuclear Engineering & Technology · Vol. 5, Issue 3, 2015 · pp. 33–37 Read article
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Thermo Analysis and Optimization Design of Industrial Vapor Compression Refrigeration Systems
Abstract: A thermodynamic analysis is performed on three different configurations of R134a two stage vapor compression refrigeration systems designed to equip cold store rooms. For economic and commercial reasons relating to agricultural actvities in southern Tuniens, two seasonal food products, dates and poultry, are selected for storage at different temperatures. Performance optimisation of the refrigeration systems is investigated under various operating conditions in order to choose the most suitable for the …
Published in Journal of Refrigeration, Air conditioning, Heating and ventilation · Vol. 2, Issue 1, 2015 · pp. 30–54 Read article
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Experimental Analysis of Capillary Tube in a Vapor Compression Refrigeration System
Abstract: Abstract A capillary is an essential deice of a vapor compression refrigeration system. It is used to reduce the condenser pressure to evaporator pressure. The refrigerant is expanded enthalpically, the reduction in pressure also reduces corresponding saturation temperature. This paper presents the analysis of expansion device accounting for three different sizes of capillary tubes. The investigations are carried out for different length of capillaries measuring 3, 3.5 and 4 m …
Published in Journal of Refrigeration, Air conditioning, Heating and ventilation · Vol. 3, Issue 1, 2016 · pp. 32–34 Read article
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Synthesis and Characterization of Sustainable, Low-Cost, Biomass-Derived Carbon Films from Hevea Brasiliensis (Rubber) Wood for Environmentally Friendly Gas Sensors with Enhanced Selectivity and Sensitivity to Polar Vapors and Hazardous Gases
Abstract: Hevea brasiliensis (rubber) wood sawdust was utilized to fabricate carbon gas sensors for detecting 1000 ppm of ethanol, methanol, acetone, carbon dioxide, and ammonia gases. The carbon particles were prepared by phosphoric acid impregnation followed by thermal activation and then fabricated into films on conductive and non-conductive substrates using the doctor blade method. X-ray diffraction (XRD) analysis revealed distinct graphitic features with peaks at the (002) and (100) planes, indicating …
Published in Journal of Thin Films, Coating Science Technology & Application · Vol. 12, Issue 1, 2025 · pp. 22–36 Read article
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Exergy Analysis of Vapor Compression Refrigeration System with Refrigerants R134a, R152a, R290 and R32
Abstract: Abstract This paper pressents exergy analysis of vapour compression refrigeration system with refrigerants R134a, R152a, R290and R32. This analysis helps to understand the effect of irreversibility on thermodynamic processes. It shows exergy losses in different components of the system and hence leads to improve the performance of different components of the system. A computational model has been developed to study the effects of evaporator temperature and condenser temperature on COP, …
Published in Journal of Refrigeration, Air conditioning, Heating and ventilation · Vol. 2, Issue 3, 2015 · pp. 11–19 Read article
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Effect of Ta2O5 as a Support in Phosphotungstic Acid Catalysts for Vapor Phase Dehydration of Glycerol to Acrolein
Abstract: The Ta2O5 supported phosphotungstic acid (HPA) catalysts were investigated for vapor phase dehydration of glycerol to acrolein and materials were synthesized by impregnation method. The above HPA catalysts were characterized by Raman spectroscopy to identify the Keggin ion and temperature programmed desorption of ammonia to explore the acidity of the catalysts. The findings of Raman spectra shows that the Keggin ion of heteropolyacid intact with support. NH3-TPD results confirm that …
Published in Journal of Catalyst & Catalysis · Vol. 2, Issue 3, 2015 · pp. 1–6 Read article