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Chemical Engineering Commons

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2004

Transport Phenomena

Selected Works

Articles 1 - 2 of 2

Full-Text Articles in Chemical Engineering

Teaching Coupled Transport And Rate Processes, Yasar Demirel Dec 2003

Teaching Coupled Transport And Rate Processes, Yasar Demirel

YASAR DEMIREL

Coupling refers to a flux occurring without its primary thermodynamic driving force; for example, mass flux without a concentration gradient called the thermal diffusion is a well-known coupled process. Coupling also refers to a flux occurring in a direction opposite to the direction imposed by its driving force; for example, a mass flux can occur from a low to a high concentration region and is called the active transport or uphill transport, such as potassium and sodium pumps coupled to chemical energy released by the hydrolysis of adenosine triphosphate (ATP) in biological systems.


Exergy-Based Performance Analysis Of Packed-Bed Solar Air Heaters, Yasar Demirel, H.H. Ozturk Dec 2003

Exergy-Based Performance Analysis Of Packed-Bed Solar Air Heaters, Yasar Demirel, H.H. Ozturk

YASAR DEMIREL

This paper presents an experimental investigation of the thermal performance of a solar air heater having its flow channel packed with Raschig rings. The packing improves the heat transfer from the plate to the air flow underneath. The dimensions of the heater are 0.9m wide and 1.9m long. The aluminium-based absorber plate was coated with ordinary black paint. The characteristic diameter of the Raschig rings, made of black polyvinyl chloride (PVC) tube, is 50mm and the depth of the packed-bed in flow channel is 60 mm. Energy and exergy analyses were applied for evaluating the efficiency of the packed-bed solar …