Kamel Hooman, Mohammad Reza Safaei, Hussein Togun and Mahidzal Dahari
In this study, closed-form solutions are presented to investigate thermohydraulics of liquid films in a rotating heat pipe. The film thickness is expressed as a function of flow…
Abstract
Purpose
In this study, closed-form solutions are presented to investigate thermohydraulics of liquid films in a rotating heat pipe. The film thickness is expressed as a function of flow rate.
Design/methodology/approach
Further, sensitivity of both film thickness and flow rate to the length of the rotating heat pipe can now be investigated using the explicit expressions presented here.
Findings
To make it easier for practical application, an approximate solution is presented on top of the exact solution.
Originality/value
Both approximate and exact solutions are then applied to note that results are in good agreement when compared to those available in the literature.
Details
Keywords
The aim of this paper is to introduce a new technique for convection visualization. This is similar to Bejan's heatlines and is even an exact match to Landau and Lifshitz's energy…
Abstract
Purpose
The aim of this paper is to introduce a new technique for convection visualization. This is similar to Bejan's heatlines and is even an exact match to Landau and Lifshitz's energy streamlines for two‐dimensional geometries.
Design/methodology/approach
The work benefits from a combination of numerical and analytical tools to show that, in two‐dimensional space, heatlines and energy streamlines are effectively the same. More importantly, the energy flux vectors are tracing both of them accurately; as verified for some cases of free and forced convection problems in this paper.
Findings
The new technique is easier to implement compared to the existing counterparts which are available in the literature. More specifically, the advantage of this new technique is that, contrary to heatlines and energy streamlines, it does not require further numerical analysis in addition to solving momentum and energy equations.
Originality/value
Energy flux vectors offer higher resolution compared to existing visualization tools.
Details
Keywords
Mehdi Miansari, M Gorji, D. D. Ganji and Kamel Hooman
– The purpose of this paper is to improve the volume-averaged models for free convection flow in porous media.
Abstract
Purpose
The purpose of this paper is to improve the volume-averaged models for free convection flow in porous media.
Design/methodology/approach
A pore scale simulation is conducted against which an independent volume-averaged solver is fine-tuned.
Findings
Micro and macro scale results can merge if proper choice of local thermal non-equilibrium and thermal dispersion models are selected. This depends on the range of Ra values investigated.
Originality/value
This is the first time a work like this is published in the literature.
Details
Keywords
Mostafa Odabaee, Michel De Paepe, Peter De Jaeger, Christophe T'Joen and Kamel Hooman
The purpose of this paper is to clarify the relationship between dust deposition effects on the thermohydraulic performance of a metal foam heat exchanger.
Abstract
Purpose
The purpose of this paper is to clarify the relationship between dust deposition effects on the thermohydraulic performance of a metal foam heat exchanger.
Design/methodology/approach
The paper uses finite volume approximation to solve the two‐dimensional volume‐averaged form of governing equations through and around a metal foam‐covered tube bundle. Modified porosity, permeability, and form drag coefficient for a dusty foam layer are obtained through the application of a thermal resistance network model.
Findings
The paper provides novel data to predict the fouling effects on the performance of foam‐wrapped tube bundles as air‐cooled heat exchangers. It is observed that depending on the deposited layer thickness, the increased pressure drop and heat transfer deterioration can be very significant.
Originality/value
This paper fulfils an identified need to study fouling effects on thermohydraulic performance of a foam heat exchanger.