Experimental investigation of thermal performance of a double-flow solar air heater having aluminium cans

Experimental energy and exergy analysis of a double-flow solar air heater having different obstacles on absorber plates

This paper reports on a modelling study of new solar air heater (SAH) system by using artificial neural network (ANN) and wavelet neural network (WNN) models. In this study, a device for inserting an absorbing plate made of aluminium cans into the double-pass channel in a flat-plate SAH. A SAH system is a multi-variable system that is hard to model by conventional methods. As regards the ANN and WNN methods, it has a superior capability for generalization, and this capability is independent on the dimensionality of the input data's. In this study, an ANN and WNN based methods were intended to adopt SAH system for efficient modelling. To evaluate prediction capabilities of different types of neural network models (ANN and WNN), their best architecture and effective training parameters should be found. The performance of the proposed methodology was evaluated by using several statistical validation parameters. Comparison between predicted and experimental results indicates that the proposed WNN model can be used for estimating the some parameters of SAHs with reasonable accuracy.

Artificial neural network and wavelet neural network approaches for modelling of a solar air heater

http://digilib.its.ac.id/public/ITS-paper-19700-2107100079-Paper4.pdf

Energy and exergy analysis of a new flat-plate solar air heater having different obstacles on absorber plates

Evaluation of thermal efficiency of double-pass solar collector with porous-nonporous media

Determination of the average coefficient of internal moisture transfer during the drying of a thin bed of potato slices

A numerical simulation model is developed to predict the forced convection performance of a dryer. This model takes into account the shrinkage phenomenon of the products during the drying process. The experimental results of the potato drying are obtained in climatic conditions similar to conditions found in natural open-air drying when the dryer is fed by air heated by a solar air flat plate collector. After a study of the influence of parameters of the drying air on the product during the drying process, we expose the experimental results and compare them with those calculated by the theoretical model. Copyright © 2001 John Wiley & Sons, Ltd.

Numerical and experimental study of dryer in forced convection

In the solar air flat plate collector, the insufficiency of the thermal exchange between the fluid and the absorber obliges the user to enhance their optimization. This low thermal exchange does not allow these systems to obtain their best performance or the best thermal efficiency. In our experimental study, which consists of a solar energy simulation, we have sought to improve the efficiency–temperature rise couple of the flat plate solar collector by considering several types of obstacles disposed in rows in the dynamic air vein of the collector. Thus, we have proceeded to the application of the best two systems (WDL1 and TL) for drying an agricultural product (Yellow Onion). By comparing with the collector without obstacles (WO), the thermal transfers and, consequently, the output temperature (TOC) and the collector efficiency (η) are clearly improved. The drying times obtained with the proposed systems are very interesting. The heat quantities obtained in the case of WDL1 are very important compared with the collector WO. However, the entry to the drying cupboard of this high temperature (TOC) in the vicinity of the solar midday must be limited to the maximal value demanded by the considered product. Copyright © 1999 John Wiley & Sons, Ltd.

Experimental study of thermal performance improvement of a solar air flat plate collector through the use of obstacles: application for the drying of ‘yellow onion’

In order to predict the performances in forced convection of a foodstuffs drier, we develop a mathematical model of numerical simulation based on the balance equations of heat and mass. We take account of the shrinkage phenomenon of the product during the drying process as well as variations of its thermal and physical properties. The experiments, for the drying of the potato, proceeded in climatic conditions similar to conditions found in natural open-air drying when the drier is fed by air heated by a solar air flat plate collector. After a study of the influence of the parameters of the drying air on the product during drying, we expose the experimental results and compare them with those calculated by the theoretical model.

H. Messaoudi

Papers

Determination of the average coefficient of internal moisture transfer during the drying of a thin bed of potato slices

Numerical and experimental study of dryer in forced convection

Experimental study of thermal performance improvement of a solar air flat plate collector through the use of obstacles: application for the drying of ‘yellow onion’

Numerical and experimental study of the drying of a potato in forced convection in a drier with racks