variavel0=<b>Paulo Eduardo Lopes Barbieri</b> - paulobarbieri@yahoo.com.br Unesp/Ilha Solteira
<b>André Luiz Seixlack</b> - andre@dem.feis.unesp.br Unesp/Ilha Solteira
<b>Abstract.</b> This work presents a numerical model to simulate the flow in finned-tube coil evaporators, the kind widely used in air conditioning and refrigeration systems. The model considers a evaporator composed of the two-phase one-dimensional homogeneous refrigerant flow inside just one tube and the air flow crossing the outside of that tube. The refrigerant pressure drop, the moisture condensation on the air side, as well as the effects of the external and internal environment conditions, are also taking into account. For the refrigerant flow, mass, momentum and energy conservation equations are solved in order to evaluate the specific mass, velocity, and temperature of the refrigerant fluid, respectively. For the air flow, energy and mass (humidity) conservation equations are solved, to obtain, respectively, the temperature and absolute humidity of the air crossing the evaporator. Also, the solution of energy conservation equation for the tube wall is used to determine the wall temperature distribution. Finite Volume Method is used all over to discretize the governing equations and a Newton-Raphson Scheme is utilized for the solution of the resulting system of equations. Results, such as air and refrigerant temperatures and tube-wall temperature distribution along the coil, are compared to data available in the open literature. Additionally, the influence of some constitutive equations on the results is analyzed.
<b>Keywords.</b> finned-tube coil evaporators, two-phase flow, refrigeration, distributed model.