Influence of outdoor air conditions on operating capacity of air conditioning systems

ABSTRACT PhD THESIS INFLUENCE OF OUTDOOR AIR CONDITIONS ON OPERATING CAPACITY OF AIR CONDITIONING SYSTEMS Mehmet Azmi AKTACÎR DEPARTMENT OF MECHANICAL ENGINEERING INSTITUTE OF NATURAL AND APPLIED SCIENCES UNIVERSITY OF ÇUKUROVA Supervisor : Prof. Dr. Tuncay YTLMAZ Year: 2005, Pages: 189 Jury : Prof. Dr. Tuncay YILMAZ Prof. Dr. Orhan BÜYÜKALACA Prof. Dr. Ertuğrul BALTACIO?LU Prof. Dr. Tuğrul O?ULATA Prof. Dr. Beşir ŞAHİN The performance of HVAC equipment changes with the variation of outside weather conditions. This thesis presents psychometric analysis of an air-conditioning system at variable outdoor air conditions for a sample building located in Adana. In this study, computer programs were developed in order to simulate the hourly operating of air conditioning systems under real operating conditions. The results obtained by the programs show that the air conditioning systems are affected by both supply air temperature and variable outdoor air conditions. In addition, this study presents a life-cycle cost (LCC) analysis using detailed load profiles and initial and operating costs to evaluate economic feasibility of constant-air-volume (CAV) and variable-air- volume (VAV) air-conditioning systems. In the analysis, two different use of the building (as a school or as an office center), two different operating scenarios for the air-conditioning system (scenario 1 and scenario 2) were considered. It was found for all the cases considered that although initial cost of the VAV system is higher than that of the CAV system, the present worth cost of the VAV system is lower than that of the CAV system at the end of the lifetime (15 years) due to lower fan operating costs. Keywords: RTS Method, cooling load, cooling coil capacity, CAV and VAV systems, variable outdoor air conditions.