Oxy Fuel Combustion Heat Transfer Mechanism
Oxy fuel combustion is a form of combustion that uses an oxygen-fuel mixture such as oxygen, hydrogen, and/or carbon dioxide to generate heat. In contrast to conventional combustion, which uses air as a fuel source, oxy fuel combustion does not generate potentially hazardous byproducts, such as nitrogen oxides and sulfuric acid. This makes the process more efficient and lower in environmental impact. This paper aims to look at the heat transfer mechanisms of oxygen fuel combustion and examine how these mechanisms can be utilized to effectively generate heat.
Heat transfer is the process of moving energy from one place to another. In oxy fuel combustion, heat transfer takes place when oxygen and fuel mix together in the combustor, or when hot combustion gases move around the combustor. The heat transfer mechanisms that are commonly utilized in oxy fuel combustion are conduction, convection, and radiation.
Conduction is the process of transferring heat energy through material contact. Conduction is the most common form of heat transfer in oxy fuel combustion. The hot combustion gases are usually in contact with a metal wall, and the heat is passed to the wall through conduction. They wall then radiates some of the heat outward, heating the surrounding air and imparting energy to the air molecules. The air molecules in turn transfer the heat to a metal surface, which further radiates the heat outward. This process functions in a cyclical fashion until all of the heat energy has been dissipated into the environment.
Convection is the process of transferring heat energy through fluid motion. In oxy fuel combustion, convection is the process of passing hot combustion gases through metal heat exchangers to heat the air before it enters the combustor. The hot combustion gases move around the heat exchanger and transfer their heat energy to the metal walls which then radiate the heat into the air. Convection is also used to transfer heat from the combustion chamber to the heat exchanger, where some of the heat is removed and the remaining heat is used to heat the incoming air.
Radiation is the process of transferring heat energy through electromagnetic waves. Radiation is the least common form of heat transfer in oxy fuel combustion, but it is an important part of the overall heat transfer mechanism. The walls of the combustor and other nearby objects can radiate heat energy into the surrounding air, and this heat energy can subsequently be transferred to the air molecules. The air molecules then transfer the heat to another object, and the process continues until the heat energy is dissipated into the environment.
In conclusion, oxy fuel combustion is an efficient and environmentally friendly form of heat transfer. The most common mechanisms of heat transfer involved in oxy fuel combustion are conduction, convection, and radiation. Conduction is the process of transferring heat energy through material contact, convection is the process of transferring heat energy through fluid motion, and radiation is the process of transferring heat energy through electromagnetic waves. With the right combination of these different heat transfer mechanisms, oxy fuel combustion can be effectively used to generate heat.
