Evaluation of VRF system with multi indoor units by experimental study and simulation analysis.

Due to worldwide demand for energy saving, many new technologies have been developed in the air conditioning field. VRF (Variable Refrigerant Flow) system is a recently developed air conditioning system which has some indoor units. There are a lot of control actuators in this system so it is difficult to find optimum operation condition to save energy. In this study in order to find the clue of conditions we construct numerical model of VRF systems and we compare to experimental data and the calculation results and we certain accuracy of model. By using simulation model, we analyze the influence of the ability of machinery and COP changing actuators’ parameter. As a result, we made sure that the constructed simulation model could predict actual behaviour of systems. Particularly, in case of light thermal load circumstance air-conditioners continue inefficient intermittent running, we analyze the cause of this condition and we make clear the clue of improvement condition.