Journal of Sustainable Energy

5

Authors: IONESCU G. C., BALOTA R.S., LOLEA M., BARLA E.

In this paper we will present the results of a simulation of an interior ventilation system which distributes fresh air in 2 office rooms. The aim is to study the distribution of the temperature inside the 2 rooms in the first seconds after the system starts. We analyzed the velocity and the temperature of the air in different scenarios. Also we are interested in finding the correct velocity which should be used by the system, in order not to determine a sudden temperature change in the room. The study is time dependent, and was simulated using Comsol 5.0 (demo version).

5

Authors: STAN IVAN F.E., MIRCEA I

The paper is structured in four parts. The first part presents the importance of thermal insulation for buildings energy economy and some insulation properties. In the second part of the paper it is described the reducing cost method to determine the energy savings. The third part of the paper includes an analysis and a comparison for an exterior wall provided with different thicknesses of insulation layer in order to determine the average savings cost. The last part presents conclusions and discussion.

6

Authors: RADULESCU V., DUMITRU S.

The paper is structured in seven parts, the last for few conclusions and finally some references. It is based on concrete measurements and observation during around 2 years. First is presented an introduction of the actual situation. In part two are mentioned the methods and hypotheses in evaluation of wind velocity distribution in boundary layers for atmospheric air, taking into account the roughness of ground surfaces. It is mentioned a concrete area, south part of Moldova. In third part is presented a solution for the geodetic model and finally are selected the altimetry solution. In chapter four is determined the influence of air density, temperature and pressure on wind turbine functioning. In the next chapters are presented the numerical model with special boundary conditions, taking into account different value of roughness and finally the obtained results. It is also estimated velocity variation during day-night. Finally is presented the vertical distribution of horizontal wind velocity for a wind farm, obviously important due the power of turbine (around 3 MW each one). Some conclusions and references are also mentioned.