We have developed the theory of a matrix air heater with a rear plate, investigated the role of individual components, and studied the performance differences for air flowing downwards and air flowing upwards through the matrix. The system is compared with an air heater of conventional design...

An air heater, in which the air first flows between metallic and cover plates and is then made to flow between two metallic plates in opposite direction, is discussed theoretically. The governing equations of the model are solved explicitly under suitable conditions. The measured values of the...

The results of a comparative study of the steady-state approach and the periodic analysis as applied to the air heater are presented. For the periodic analysis, the meteorological data are represented by a Fourier series. The periodic analysis is carried out by taking half-hourly and hourly...

We have investigated a fin-type air heater, both experimentally and theoretically. In the experimental set-up, the fins are integrated with the upper plate of the conventional duct-type air heater with single glazing. The experiments were performed on two clear days for two different mass-flow...

We have developed the theory for a four-pass air heater. We have also studied the system performance with one, two, and three passes. The effect of the number of glass cover plates on one, two, and three passes has also been investigated. It is shown that the multiple-pass air heater performs...

The high cost of equipment and installation of the common metallic flat plate collector type water heating systems (with virtually no energy storage) make them unsuitable for large-scale adoption in the rural areas of underdeveloped countries. In order to popularize solar energy in the rural...

In a conventional still, because the water condenses underneath a glass cover, its temperature becomes quite high. During the period of maximum sunshine, the glass temperature is higher than the dew point of the air-vapour mixture inside the still. Thus the yields of these kinds of stills are...

A water heater utilising a material which changes phase for storage of solar energy is discussed. The transient analysis is carried out by replacing the solid-liquid block of the phase-changing material by a fictitious solid and assuming that the solid-liquid boundary remains stationary...

Solar air heaters use either one or two glazings. However, large absorber area collectors normally do not use a second glazing because of high cost of the two-glaze unit. An analysis of a solar air heater with a partial second glazing is presented. The efficiency of the system is calculated as a...

A new series of resolvable PBIB(3) designs with two replications has been proposed along with a simple method of analysis. These designs form a generalization of circular lattice designs of Rao (1956). Copyright Springer-Verlag 2004