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...

We have investigated the performance of a solar water heater with collector and baffle plate for six continuous days during the summer and winter seasons. The following cases were studied: 1.(i) no flow,2.(ii) constant water flow rates,3.(iii) intermittent flow to meet requirements of hot water,...

The performance of a built-in storage water heater can be improved by using a baffle plate in the absorber tank. We have studied the following different design conditions: 1.(i) a water heater with baffle plate and with night insulation cover,2.(ii) with baffle plate and without night insulation...

We present a theoretical analysis of three different configurations of double exposure solar air heaters. The heat-balance equations are written in each case and are solved explicitly. The periodic responses have been studied for different combinations of parameters. Measured values of solar...

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 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...

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 theoretical investigation for optimizing collector-cost effectiveness is carried out by considering various tube diameters, materials, tube spacing, fin materials, and thicknesses for black and other paints. The bond conductance is taken into account for various joining techniques. Various...

This paper deals with efforts to improve the performance of conventional, duct- type air heaters by providing rectangular fins in the air passage between the absorber and the rear plate. For this configuration, a mathematical model is developed by writing the energy balance equations at various...

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...