This paper presents a comparison of optimized mixed-mode and indirect-mode natural convection solar dryers for maize. The mixed-mode and indirect-mode solar drying simulation models were validated against results from a laboratory solar dryer with experiments carried out under a solar simulator...

In this paper, experimental investigation into the basic characteristics of solar thermal conversion using supercritical CO2 natural convection are presented. Natural circulation of supercritical fluids can be easily induced and even a small change in temperature can result in large change in...

The non-uniformity of the air temperatures and the slow flow rate at the plane collector exit constitute the main cause of the limitations of the solar drying systems. In order to obtain an uniform and a variable flow rate for different uses, a hot air generator using concentrated solar...

The time mismatch between energy availability and energy demand with solar domestic hot water (SDHW) systems is often solved using energy storage. Energy storage systems typically employ water for thermal energy storage, however, water storage takes up considerable space and weight due to the...

An experimental investigation into the performance of a solar crop dryer with solar chimney and no air preheating is described. Tests were first performed on the cabinet dryer, using a normal chimney. The trials were repeated with a solar chimney. Still with the solar chimney, further trials...

In this paper, the computational fluid dynamics technique (CFD) was used for air flow simulation in the solar chimney. The flow is assumed laminar, unsteady and incompressible. The air flow model consisted of a system of governing equations continuity, momentum, energy are solved for 2D...

Optimization of industrial processes for higher energy efficiency may be effectively carried out based on the thermodynamic approach of entropy generation minimization (EGM). This approach provides the key insights on how the available energy (exergy) is being destroyed during the process and...

Natural convection is the governing phenomena in many material processing applications. The conventional method of uniform heating at the bottom wall of an enclosure may result in inadequate thermal mixing and poor temperature distribution leading energy wastage. In this work, an alternative,...

In this study, free convection heat transfer in a concentric annulus between a cold square and heated elliptic cylinders in presence of magnetic field is investigated. The square and elliptic cylinders are maintained at uniform temperatures and it is assumed that the walls are insulating...

Sloped solar chimney system is a solar chimney power plant with a sloped collector. Practically, the sloped collector can function as a chimney, then the chimney height can be reduced and the construction cost would be reduced also. A mathematical model based on the continuity, momentum, energy,...