الفهرس 
Environmental Impacts of water and air thermal pollutionOnly 14 pages are availabe for public view
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Abstract
Steam power plants generate most of the electricity throughout the world. One of the most important equipments of the steam power plant is the steam surface condenser, which is a huge complex shell and tube heat exchanger. An improvement in the power plant thermal efficiency can be achieved by reducing the turbine exhaust pressure. The basic control of the condenser pressure is the inlet coolant fluid temperature. The refrigerants have a normal temperature in liquid phase much lower and accordingly greatly higher heat rate than water and air can be achieved. Therefore, the main objective of the current research is to study the performance of steam plant condenser when a vapor compression refrigeration system is used to cool the plant condenser rather than ground or surface water which is used in most current steam power plants around the world. The current investigation provides an analytical, experimental and numerical study for steady performance of steam condenser working under various operational conditions. The analytical study is conducted to select the best efficient refrigerants to be suitable for condenser cooling. Then based on the analytical conclusions, the indoor experimental set up is constructed. The experimental test rig comprises three interacted loops for releasing heat of steam condensation to environment. In the experimental facility, the effect of using vapor compression refrigeration system will be introduced through the required refrigerant mass flow rate to condense one kg of steam. Also, the effect of operating conditions on refrigeration system COP is studied. Moreover, the heat transfer characteristics inside the steam condenser at different inlet coolant temperatures and mass flow rates and condenser pressures will be discussed. CFD trial is used to visualize heat and mass transfer inside one half of the experimental steam condenser. The numerical simulation encounters two main problems, the huge computational time required for the whole plane simulation of the present condenser, besides the difficulties in simulation the functions of steam condenser outlet valve. These two main problems will be addressed with fluid flow visualization.