Recycling heat generated in the condenser of a refrigeration cycle by compression

• Grant number: 08/06270-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2008
• Effective date (End): September 30, 2009
• Field of knowledge: Engineering - Mechanical Engineering - Thermal Engineering
• Principal Investigator: Alcides Padilha
• Grantee: Murilo Martinho de Oliveira
• Host Institution: Faculdade de Engenharia (FE). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil

Abstract

Since the beginning of the 20th century, natural resources of earth have been extracted in an intense way, without worrying about their exhaustion. Thus, with the population increasing, the atmosphere pollution, the soil degradation and the extraction of all resources in earth, energy crisis has bloom since traditional sources of energy are falling down to exhaustion invoking needs of alternative energy sources. People worried about environmental preservation have intensified the process of developing renewable energy around the world to help natural alternative energy sources -- sun, wind, rivers, waves, tide, animal & vegetable residue, groundwater heat, among others - in the fulfillment of human needs. By using renewable energy sources you certainly contribute to minimize environment pollution, improve life quality and also help ensuring availability of natural resources for future generations. Once used efficiently renewable energy sources combined with other traditional forms of energy can potentially slow down the phenomenon of climate change, especially global warming. The phantom of economic feasibility for renewable energy installation has been gone. Currently modest budgets have been enough to develop small renewable energy systems especially when supported by available resources. At home, for instance, it would be helpful to search for methods of taking advantage of recycling thermal waste of equipment turning it into a process of heating water which can be stored in a tank. This method would have a huge range of behavior, characteristics and size. Following the idea, changes are proposed in a pre-built test bench including a cylindrical instrumented thermal storage tank. Research goal is to increase (or maximize) the performance coefficient of two coolers (refrigerators) of equal capacity: a conventional one and a modified one. A cooler including a standard condenser plus a shell-tube based heat exchange system monitor stored hot water thru the technique of thermal stratification. The thermal waste collected through the principle of thermal siphon is stored in the form of thermal energy. According to the results the system performance coefficient calculated by the technique of theoretical and experimental thermal losses increased significantly. The behavior of dynamic "termoclinas" was also observed showing temperature variation as the time passed by. Modified cooler presented great feasibility to generate thermal comfort to users besides heating domestic water. (AU)