scholarly journals The study of a consistent pattern of heat and mass transfer at drying fiber-forming polymers

2021 ◽  
Vol 2119 (1) ◽  
pp. 012153
Author(s):  
Yu A Geller ◽  
G I Efremov ◽  
I S Antanenkova ◽  
Yu V Shatskikh
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Polyethylene Terephthalate ◽  
Water Sorption ◽  
Characteristic Time ◽  
Consistent Pattern ◽  
Polyamide 66 ◽  
Intensity Index ◽  
Stationary Method

Abstract In this article, the consistent pattern of mass transfer in the process of drying granular polyethylene terephthalate (PET), polycaproamide (PCA), and polyamide 66 (PA 66) were studied. A modified quasi-stationary method was used to analyze the data. The characteristic time and the hydrodynamic intensity index were obtained based on experimental data. Some features of water sorption and desorption by fiber-forming polymers were studied.

Simultaneous heat and mass transfer during evaporation from a film of liquid into the turbulent gas

1982 ◽  
Vol 47 (3) ◽  
pp. 766-775 ◽  
Author(s):  
Václav Kolář ◽  
Jan Červenka
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Liquid Film ◽  
Heat And Mass Transfer ◽  
Driving Forces ◽  
Proper Definition ◽  
Definition Of ◽  
Simultaneous Heat ◽  
Theory And Experiment

The paper presents results obtained by processing a series of published experimental data on heat and mass transfer during evaporation of pure liquids from the free board of a liquid film into the turbulent gas phone. The data has been processed on the basis of the earlier theory of mechanism of heat and mass transfer. In spite of the fact that this process exhibits a strong Stefan's flow, the results indicate that with a proper definition of the driving forces the agreement between theory and experiment is very good.

CFD Simulation of Hydrodynamics, Heat and Mass Transfer Simultaneously in Structured Packing

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
M.R. Khosravi Nikou ◽  
M.R. Ehsani ◽  
M. Davazdah Emami
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Pressure Drop ◽  
Heat And Mass Transfer ◽  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Theoretical Plate ◽  
Absolute Relative Error ◽  
Gas Liquid Flow ◽  
Counter Current

This paper describes the results of computational fluid dynamic modeling of hydrodynamics, heat and mass transfer simultaneously in Flexipac 1Y operated under a counter-current gas-liquid flow condition. The simulation was performed for a binary mixture of methanol-isopropanol distillation. The pressure drop, the height of equivalent to theoretical plate (HETP) and temperature distribution across the column were calculated and compared with experimental data. The mean absolute relative error (MARE) between CFD predictions and experimental data for the pressure drop, HETP and temperature profile are 20.7%, 12.9% and 2.8%, respectively.

Study of Condensation Flow Patterns and Heat Transfer Characteristic on a Horizontal Tube Bundle

2016 ◽  
Author(s):  
Hongfang Gu ◽  
Qi Chen ◽  
Zhe Zhang ◽  
Haiyang Guo
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Mass Transfer ◽  
Flow Regime ◽  
Heat And Mass Transfer ◽  
Tube Bundle ◽  
Flow Patterns ◽  
Heat Transfer Characteristics ◽  
Controlled Flow ◽  
Condensation Flow

The numerous studies on condensation flow patterns and heat transfer were focused on the horizontal inside single tube. A number of heat and mass transfer correlations are used for design of shellside condensers based on tubeside condensation flow regimes. Due to a complex geometry and measurement difficulty in a tube bundle, there are few publications reported on shellside condensation flow regime and heat transfer characteristics. To investigate the condensation flow patterns and heat and mass transfer mechanism at the different flow regimes, a horizontal shellside condenser was tested from a multipurpose condensation rig recently. The horizontal test bundle is made of 36 tubes with the staggered tube layout. The tube OD is 19 mm and the tube length is 1.0 m using stainless steel. Four visualization windows were placed on the front and back sides on the shell for photographing condensation flow patterns. Steam and steam/air mixture were used as the test fluids. The condensation flow patterns, condensate film thickness and droplets distribution were recorded using a high-speed digital camera at a wide range of condensation process conditions. The experimental data show that the condensation flow regime changes from the shear-controlled flow to gravity-controlled flow depending on the vapor and condensate loads, bundle location and the concentration of the non-condensable gas. These experimental data provide a fundamental approach for developing the heat and mass transfer correlateons at different shellside condensation patterns. This paper presents the experimental result on shellside condensation patterns associated with heat transfer characteristics.

Heat and Mass Transfer Analogy of Steam Condensation With Air Over Vertical External Surface

2016 ◽  
Author(s):  
Jiqiang Su ◽  
Yuxiang Wu ◽  
Shuliang Huang ◽  
Huiqiang Xu ◽  
Yanmin Zhou
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
External Surface ◽  
Vertical Tube ◽  
External Diameter ◽  
Thermodynamic Process ◽  
Layer Model ◽  
Steam Condensation ◽  
Predicted Values

During the steam condensation, the presence of non-condensable gases is an important issue affecting the efficiency of the whole thermodynamic process. For this reason, many researchers investigated it by theoretical or experimental methods. A heat and mass transfer analogy model on steam condensation in presence of air over the vertical external surface based on the diffusion layer model is modified in the present paper. Based on previous authors’ experience, the suction effect at the gas-liquid interface and other analogy drawbacks are identified and overcome by supplementing it with more detailed analysis as well as targeted experiments. The experimental data obtained for condensation, outside vertical tube with an external diameter of 38 mm, of air/steam and helium/air/steam mixture, have been used to verify the present heat and mass transfer analogy formulation. By comparing against different available experimental data and previous formulations, the heat and mass transfer analogy formulation is demonstrated to be a accurate enough theoretical approximation. The deviation between predicted values of the new model and experiment results of this paper is less than 15% which has relative higher precision.

Steady-State Performance of a Small-Scale Liquid-to-Air Membrane Energy Exchanger for Different Heat and Mass Transfer Directions, and Liquid Desiccant Types and Concentrations: Experimental and Numerical Data

2013 ◽  
Vol 135 (12) ◽  
Author(s):  
Davood Ghadiri Moghaddam ◽  
Philip LePoudre ◽  
Robert W. Besant ◽  
Carey J. Simonson
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Steady State ◽  
Heat And Mass Transfer ◽  
Salt Solution ◽  
Test Facility ◽  
Small Scale ◽  
Air Cooling ◽  
Test Cases ◽  
Membrane Energy

A liquid-to-air membrane energy exchanger (LAMEE) is an energy exchanger that allows heat and moisture transfer between air and salt solution flows through a semipermeable membrane. For the first time, a novel small-scale single-panel LAMEE test facility is used to experimentally investigate the effect of the direction of heat and mass transfers for the air and salt solution flows, and the effect of different salt solution types and concentrations on the LAMEE effectiveness. The data for steady-state effectiveness of the LAMEE are compared to the simulation results of a numerical model. Two studies are conducted; first a study based on different heat and mass transfer directions (four test cases), and second a study focused on the influence of solution types and concentration on LAMEE performance. For the first study, NTU = 3 and four different heat capacity ratios (i.e., Cr* = 1, 3, 5, 7) are used, with a LiCl salt solution in the exchanger. Mass and energy balances for all the test cases and the repeatability of the experimental data for the air cooling and dehumidifying test case show that the experimental data are repeatable and within an acceptable uncertainty range. The results show increasing effectiveness with increasing Cr*, and good agreement between the numerical and experimental results for both air cooling and dehumidifying and air heating and humidifying test cases. In the second study, two different salt solutions (i.e., LiCl and MgCl2), and three different concentrations for the LiCl solution (i.e., 25%, 30%, and 35%) are selected to investigate the effect of different salt solution types and concentrations on the performance of the LAMEE. A maximum difference of 10% is obtained for the LAMEE total effectiveness data with the different salt solution types and concentrations. The results show that both the salt solution type and concentration affect the LAMEE effectiveness, and changing the concentration is one way to control the supply air outlet humidity ratio.

scholarly journals Experiments and Modelling Techniques for Heat and Mass Transfer in Light Water Reactors

2009 ◽  
Vol 2009 ◽  
pp. 1-11 ◽  
Author(s):  
W. Ambrosini ◽  
M. Bucci ◽  
N. Forgione ◽  
A. Manfredini ◽  
F. Oriolo
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Nuclear Reactor ◽  
Model Development ◽  
Experimental Tests ◽  
Finned Tubes ◽  
Water Reactors ◽  
Eu Project ◽  
The University

The paper summarizes the lesson learned from theoretical and experimental activities performed at the University of Pisa, Pisa, Italy, in past decades in order to develop a general methodology of analysis of heat and mass transfer phenomena of interest for nuclear reactor applications. An overview of previously published results is proposed, highlighting the rationale at the basis of the performed work and its relevant conclusions. Experimental data from different sources provided information for model development and assessment. They include condensation experiments performed at SIET (Piacenza, Italy) on the PANTHERS prototypical PCCS module, falling film evaporation tests for simulating AP600-like outer shell spraying conditions, performed at the University of Pisa, experimental data concerning condensation on finned tubes, collected by CISE (Piacenza, Italy) in the frame of the INCON EU Project, and experimental tests performed in the CONAN experimental facility installed at the University of Pisa. The experience gained in these activities is critically reviewed and discussed to highlight the relevant obtained conclusions and the perspectives for future work.

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