Impact of Layered Soil on Foundation Heat Transfer for Slab-On Grade Floors

2009 ◽  
Author(s):  
Nizar Khaled ◽  
Moncef Krarti
Keyword(s):  
Heat Transfer ◽  
Temperature Estimation ◽  
Soil Medium ◽  
Coupled Heat Transfer ◽  
Building Foundation ◽  
Soil Thermal Properties ◽  
Homogeneous Soil ◽  
Periodic Heat ◽  
The Impact ◽  
Zone Temperature

This paper presents an analytical solution for the steady-periodic heat transfer for a typical slab-on-grade floor building foundation beneath non-homogeneous soil medium. The impact of the above-grade walls on ground-coupled heat transfer is accounted for in the presented solution. The Inter-zone Temperature Estimation Profile (ITPE) technique is utilized to obtain the 3-D solutions to determine soil temperature distributions and to estimate foundation heat loss/gain from slab-on-grade floors. The impact of the non-homogeneous soil properties on the transient foundation heat transfer is investigated for various slab configurations and soil thermal properties.

Impact of Layered Soil on Foundation Heat Transfer for Slab-On Grade Floors

2012 ◽  
Vol 134 (2) ◽  
Author(s):  
Nizar Khaled ◽  
Khaled Rouissi ◽  
Moncef Krarti
Keyword(s):  
Heat Transfer ◽  
Analytical Solution ◽  
Soil Temperature ◽  
Soil Properties ◽  
Heat Loss ◽  
Layered Soil ◽  
Soil Medium ◽  
Coupled Heat Transfer ◽  
Building Foundation ◽  
The Impact

This paper presents an analytical solution associated with the steady-periodic heat transfer for a typical slab-on-grade floor building foundation in contact with a nonhomogeneous soil medium. In particular, the solution accounts for the impact of the above-grade wall thickness on the ground-coupled heat transfer. The interzone temperature estimation profile (ITPE) technique is utilized to obtain the analytical solution to determine soil temperature distributions and to estimate foundation heat loss/gain from slab-on-grade floors. In this paper, the impact of the nonhomogeneous soil properties on the transient foundation heat transfer is investigated for various slab configurations and soil thermal properties. The presented solution presents the first ITPE analytical solution for building foundation coupled with layered soil medium. The results indicate that nonhomogeneous soil properties have a significant effect on soil temperature distribution and on total slab heat loss. In particular, it is found that an error of up to 20% in estimating total slab heat transfer can be incurred if homogeneous soil medium is considered instead of a two-layered ground.

An Evaluation of a NN-Based Model for the Prediction of Foundation Heat Transfer From Basements

2001 ◽  
Author(s):  
Mustafa Salehi ◽  
Moncef Krarti
Keyword(s):  
Heat Transfer ◽  
Network Architecture ◽  
Model Development ◽  
Training Data ◽  
Testing Procedures ◽  
Coupled Problem ◽  
Building Foundation ◽  
Soil Thermal Properties ◽  
Input Variables ◽  
Indoor And Outdoor

Abstract In this paper, a feed-forward artificial neural network module is presented to predict seasonal variations of foundation heat transfer from conditioned basements. The training data for the NN-based module were obtained from a detailed solution of the ground-coupled problem. Input variables for the NN module include foundation geometric dimensions, insulation configuration, indoor and outdoor temperatures, and soil thermal properties. The paper discusses the network architecture and the training and testing procedures. The predictions of the NN-based module are compared to a correlation-based method for a set of basement configurations. The main conclusion of the paper is that NNs can predict seasonal variation of building foundation heat transfer with high accuracy and little effort for model development.

Impact of Above-Grade Walls on Three-Dimensional Building Foundation Heat Transfer From Slab-On Grade Floors

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Moncef Krarti
Keyword(s):  
Heat Transfer ◽  
Three Dimensional ◽  
Closed Form Solution ◽  
Form Solution ◽  
Heat Losses ◽  
Dimensional Solution ◽  
Simplified Approach ◽  
Coupled Heat Transfer ◽  
Profile Estimation ◽  
The Impact

This paper presents a new three-dimensional analytical solution for transient ground-coupled heat transfer associated with slab-on-grade floor building foundations. The impact of above-grade walls on ground-coupled heat transfer is accounted for in the presented solution. The interzone temperature profile estimation (ITPE) technique is utilized to obtain the 3D solution suitable to determine soil temperature distributions and to estimate foundation heat loss/gain from slab-on-grade floors. The ITPE results are validated against results obtained from a closed-form solution in the case of steady-state conditions. It is found that that the above-grade walls can significantly affect the foundation heat losses especially for uninsulated slabs. Moreover, a simplified approach is proposed to obtain three-dimensional foundation heat losses from a two-dimensional solution.

Analysis of Heat and Moisture Transfer Beneath Freezer Foundations—Part I

2004 ◽  
Vol 126 (2) ◽  
pp. 716-725 ◽  
Author(s):  
Pirawas Chuangchid ◽  
Pyeonchan Ihm ◽  
Moncef Krarti
Keyword(s):  
Heat Transfer ◽  
Moisture Transfer ◽  
Experimental Tests ◽  
Frozen Soil ◽  
Heat And Moisture Transfer ◽  
Conduction Model ◽  
Coupled Heat Transfer ◽  
Time Required ◽  
Heat And Moisture ◽  
The Impact

This paper provides a numerical solution for simultaneous heat and moisture transfer within frozen soil beneath slab foundations of refrigerated warehouses. The developed solution is validated using data from experimental tests. A parametric analysis is then performed to determine the impact of slab insulation levels and to estimate the time required to reach steady-state ground-coupled heat transfer conditions. Finally, the solution is utilized to determine an effective soil thermal conductivity that could be used in a purely heat conduction model for ground-coupled heat transfer beneath freezers.

Experimental study of thermohydraulic characteristics and irreversibility analysis of novel axial corrugated tube with spring tape inserts

2020 ◽  
Vol 92 (3) ◽  
pp. 30901
Author(s):  
Suvanjan Bhattacharyya ◽  
Debraj Sarkar ◽  
Ulavathi Shettar Mahabaleshwar ◽  
Manoj K. Soni ◽  
M. Mohanraj
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Thermal Performance ◽  
Working Fluid ◽  
The Novel ◽  
Heat Exchanger Tube ◽  
Heat Transfer Augmentation ◽  
Corrugated Tube ◽  
The Impact ◽  
Exchanger Tube

The current study experimentally investigates the heat transfer augmentation on the novel axial corrugated heat exchanger tube in which the spring tape is introduced. Air (Pr = 0.707) is used as a working fluid. In order to augment the thermohydraulic performance, a corrugated tube with inserts is offered. The experimental study is further extended by varying the important parameters like spring ratio (y = 1.5, 2.0, 2.5) and Reynolds number (Re = 10 000–52 000). The angular pitch between the two neighboring corrugations and the angle of the corrugation is kept constant through the experiments at β = 1200 and α = 600 respectively, while two different corrugations heights (h) are analyzed. While increasing the corrugation height and decreasing the spring ratio, the impact of the swirling effect improves the thermal performance of the system. The maximum thermal performance is obtained when the corrugation height is h = 0.2 and spring ratio y = 1.5. Eventually, correlations for predicting friction factor (f) and Nusselt number (Nu) are developed.

scholarly journals Approximate Analytical Analysis of Unsteady MHD Mixed Flow of Non-Newtonian Hybrid Nanofluid over a Stretching Surface

Fluids ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 138
Author(s):  
Ali Rehman ◽  
Zabidin Salleh
Keyword(s):  
Heat Transfer ◽  
Differential Equations ◽  
Base Fluid ◽  
Research Work ◽  
Hybrid Nanofluid ◽  
Stretching Surface ◽  
Optimal Homotopy Analysis Method ◽  
Analytical Analysis ◽  
Transfer Ratio ◽  
The Impact

This paper analyses the two-dimensional unsteady and incompressible flow of a non-Newtonian hybrid nanofluid over a stretching surface. The nanofluid formulated in the present study is TiO2 + Ag + blood, and TiO2 + blood, where in this combination TiO2 + blood is the base fluid and TiO2 + Ag + blood represents the hybrid nanofluid. The aim of the present research work is to improve the heat transfer ratio because the heat transfer ratio of the hybrid nanofluid is higher than that of the base fluid. The novelty of the recent work is the approximate analytical analysis of the magnetohydrodynamics mixed non-Newtonian hybrid nanofluid over a stretching surface. This type of combination, where TiO2+blood is the base fluid and TiO2 + Ag + blood is the hybrid nanofluid, is studied for the first time in the literature. The fundamental partial differential equations are transformed to a set of nonlinear ordinary differential equations with the guide of some appropriate similarity transformations. The analytical approximate method, namely the optimal homotopy analysis method (OHAM), is used for the approximate analytical solution. The convergence of the OHAM for particular problems is also discussed. The impact of the magnetic parameter, dynamic viscosity parameter, stretching surface parameter and Prandtl number is interpreted through graphs. The skin friction coefficient and Nusselt number are explained in table form. The present work is found to be in very good agreement with those published earlier.

scholarly journals Efficiency Improvement of Miniaturized Heat Exchangers

Fluids ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 25
Author(s):  
Iris Gerken ◽  
Thomas Wetzel ◽  
Jürgen J. Brandner
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Enhancement ◽  
Heat Exchangers ◽  
Assessment Method ◽  
Flow Path ◽  
Transfer Enhancement ◽  
Pressure Losses ◽  
Pin Fin ◽  
Additional Pressure ◽  
The Impact

Micro heat exchangers have been revealed to be efficient devices for improved heat transfer due to short heat transfer distances and increased surface-to-volume ratios. Further augmentation of the heat transfer behaviour within microstructured devices can be achieved with heat transfer enhancement techniques, and more precisely for this study, with passive enhancement techniques. Pin fin geometries influence the flow path and, therefore, were chosen as the option for further improvement of the heat transfer performance. The augmentation of heat transfer with micro heat exchangers was performed with the consideration of an improved heat transfer behaviour, and with additional pressure losses due to the change of flow path (pin fin geometries). To capture the impact of the heat transfer, as well as the impact of additional pressure losses, an assessment method should be considered. The overall exergy loss method can be applied to micro heat exchangers, and serves as a simple assessment for characterization. Experimental investigations with micro heat exchanger structures were performed to evaluate the assessment method and its importance. The heat transfer enhancement was experimentally investigated with microstructured pin fin geometries to understand the impact on pressure loss behaviour with air.

Sign in / Sign up

Export Citation Format

Share Document