Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
Browse
2 results
Search Results
Master Thesis A Study on Combination of Electrical Heater, Exhaust Air Heat Recovery Unit and Solar Energy Assisted System for Building Ventilation(Izmir Institute of Technology, 2012) Özyoğurtçu, Gamze; Mobedi, Moghtada; Mobedi, Moghtada; 03.10. Department of Mechanical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyA study on the ventilation of a building by using solar energy, a heat recovery unit and electrical heater (if it is needed) is performed. The heat recovery unit is used to increase temperature of fresh air by using thermal energy of the return air. Then, the thermal energy stored in a sensible tank is employed to increase the temperature of air leaving the heat recovery unit. If the air temperature at the coil outlet is less than the supply temperature, electrical heater is operated. The study is performed by TRNSYS software for the period of 1st of November to 31st of March. The ventilation system operates from 17:00 to 24:00 where a lower ambient temperature exists compared during the day period. The obtained results show that a ventilation system with solar assisted and heat recovery unit can considerably reduce ventilation energy consumption. The use of solar assisted ventilation system with heat recovery unit reduces energy consumption by 80% if it is compared with conventional ventilation system in which only an electrical heater operates. Furthermore, it is found that the design of ventilation systems without energy of electrical heater is possible. The study s performed by using weather data of Izmir city in Turkey. The supply temperature of fresh air is assumed as 22°C.Master Thesis Measurement and Comparison of Solar Radiation Estimation Models for Izmir/Turkey: Izmir Institute of Technology Case(Izmir Institute of Technology, 2011) Vecan, Didem; Özerdem, Barış; Özerdem, Mehmet Barış; 03.10. Department of Mechanical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologySolar energy technologies offer a clean, renewable and domestic energy source, and are essential components of a sustainable energy in the future. Proper and adequate information on solar radiation and its components at a given location is very essential in the design of solar energy systems. Due to Turkey’s location, solar energy potential is abundantly available. Consequently, it is worth to examine and conduct research on the solar energy source. In this study, the global solar radiation data in Izmir were analyzed based on 3 years of global solar radiation data measured on a horizontal surface on the campus area of Izmir Institute of Technology. Actual data readings were made on a ten minute basis from January, 2005 to December, 2007. Monthly-average daily global radiation has been analyzed. A linear, a second-order and third order equations are designed for the calculation of the monthly-average daily global radiation in Izmir. The main objective is to estimate global solar radiation via models mentioned in the literature both for Turkey in general and for Izmir specifically; and to compare the results with the three new developed models. In addition to global solar radiation, diffuse solar radiation data were analyzed and proposed models for estimating the monthly average daily diffuse solar radiation, as well. Four new models were developed for diffuse solar radiation calculations and nine models from the literature have been used. In order to confirm the results, four statistical methods have been used namely; mean bias error (MBE), root mean square (RMSE), t-statistic and relative percentage error. According to the statistical evaluation, it may be concluded that the new polynomial equation predict the monthly-average daily global solar radiance better than other available models.