Case Studies of Coupled Heat and Moisture Diffusion in Wool Beds

1969 ◽  
Vol 39 (2) ◽  
pp. 166-172 ◽  
Author(s):  
H. G. David ◽  
P. Nordon
Keyword(s):  
Mathematical Model ◽  
Relative Humidity ◽  
Heat Flow ◽  
Case Studies ◽  
Satisfactory Agreement ◽  
Moisture Diffusion ◽  
Wool Fabrics ◽  
Flow Through ◽  
Coupled Heat And Moisture ◽  
Heat And Moisture

The predictions from a previously developed mathematical model for coupled heat and moisture diffusion in beds of hygroscopic fibers have been tested against experimental observations on wool bales and wool fabrics. The experiments on wool bales were concerned with the changes in regain and temperature consequent upon changes in the relative humidity and temperature of the surrounding air. The experiments on fabrics included measurements of temperature and regain during Hoffman pressing and measurements of heat flow through the fabric during changes in regain. Satisfactory agreement was found between the predictions from the model and the experimental observations.

scholarly journals Verification and application of a mathematical model for the assessment of the effect of guiding walls on the hydraulic efficiency of chlorination tanks

2002 ◽  
Vol 4 (4) ◽  
pp. 245-254 ◽  
Author(s):  
Anastasios I. Stamou
Keyword(s):  
Mathematical Model ◽  
Flow Field ◽  
Satisfactory Agreement ◽  
Hydraulic Efficiency ◽  
Flow Through ◽  
Initial Geometry

A mathematical model is applied to the tank of Kipseli in Athens, Greece, which is used for storage, balancing and emergency chlorination. A Flow-Through Curve (FTC) experiment is performed for the initial geometry of the tank. The shape and the characteristics of the FTC show a very poor hydraulic efficiency, with extensive short-circuiting, intense mixing and low detention times. To improve the hydraulic efficiency of the tank the use of four alternative arrangements of guiding walls is examined by the model. Prior to its application, the model is verified by comparing the predicted FTC with the experimental. A satisfactory agreement is observed between the calculated and the experimental curves. Then the model is applied to calculate the flow field and the FTC for the four arrangements. Calculations are compared and the arrangement which shows the highest hydraulic efficiency is proposed for construction.

Numerical modelling of heat and moisture transport through bentonite–sand buffer

1992 ◽  
Vol 29 (6) ◽  
pp. 1044-1059 ◽  
Author(s):  
H. S. Radhakrishna ◽  
A. M. Crawford ◽  
B. Kjartanson ◽  
K. C. Lau
Keyword(s):  
Numerical Model ◽  
Nuclear Waste ◽  
Computer Code ◽  
Transport Parameters ◽  
Deep Geological Disposal ◽  
Heat And Moisture Transport ◽  
Flow Through ◽  
Coupled Heat And Moisture ◽  
Underground Research Laboratory ◽  
Heat And Moisture

A computer code TRUCHAM developed to model the coupled heat and moisture flow through a porous medium is used to assess the thermohydraulic performance of the clay-based engineered barrier encapsulating nuclear waste containers in a deep geological disposal vault in the borehole emplacement concept. This paper contains an overview of the development of the numerical model and its application to the buffer–container experiment at the Underground Research Laboratory of Atomic Energy of Canada Limited Research. The thermohydraulic transport parameters required for the analysis were determined by specially designed laboratory experiments. The needs for further development of the model and the material properties are identified. Key words : buffer, clay barrier, coupled heat and moisture, heater experiment, numerical model, nuclear waste disposal, thermal diffusivity, unsaturated soil.

Effects of coupled heat and moisture and load damage on chloride transport in concrete

2021 ◽  
pp. 1-40
Author(s):  
Hongguang Min ◽  
Weiping Zhang
Keyword(s):  
Relative Humidity ◽  
Temperature Gradient ◽  
Exposure Time ◽  
Transport Model ◽  
Chloride Transport ◽  
Humidity Gradient ◽  
Concrete Damage ◽  
Chloride Profiles ◽  
Coupled Heat And Moisture ◽  
Heat And Moisture

This paper presents a thoroughgoing research on chloride transport in damaged concrete. Effects of temperature and temperature gradient on chloride transport was investigated along with effects of relative humidity, humidity gradient, concrete damage and exposure time. The higher the temperature and the greater the humidity gradient were, the quicker chloride transport was. Moisture transport increased as concrete damage increased, while chloride transport decreased incrementally. Considering the effect of coupled heat and moisture on chloride transport in concrete, a chloride transport model was established and verified by experiments. Chloride profiles in damaged concrete were related to temperature, temperature gradient, relative humidity and humidity gradient. The chloride attack rate decreased with increasing concrete damage and exposure time. Hence, coupled heat and moisture as well as concrete damage had significant effects on chloride transport in damaged concrete, and effects of concrete damage on chloride transport should be considered when determining chloride profiles in damaged concrete.

Coupled Heat and Moisture Flow Through Soils

1984 ◽  
Vol 110 (12) ◽  
pp. 1766-1784 ◽  
Author(s):  
Haran S. Radhakrishna ◽  
Ka‐Ching Lau ◽  
Adrian M. Crawford
Keyword(s):  
Moisture Flow ◽  
Flow Through ◽  
Coupled Heat And Moisture ◽  
Heat And Moisture ◽  
Heat And Moisture Flow
Sign in / Sign up

Export Citation Format

Share Document