Raluca Malciu

Dynamic Analysis of a Mobile Mechanical System with Deformable Elements

The paper presents a method for studying mechanisms with deformable elements, based on overlapping the solid rigid motion over the elastic solid one, in order to identify the dynamic response of the system. Modeling was based on finite element method, so the cinematic elements were meshed in bar type finite elements and the degrees of freedom per node were settled according to the motion character (planar or spatial). A Lagrange formulation of the finite element was adopted for the deformable elements connected in multibody systems. In order to define the joints constraints, the conditions for compatibility between elements were defined using a Boolean constant matrix. Computer processed results were verified by an experimental model.

Elastodynamic Analysis of the Sucker Rod Pumping System Mechanism

The paper aims to identify the dynamic response of the oil pumping unit system mechanism using the analytical method and the experimental method. By numerical processing of the developed mathematical models for longitudinal and transverse vibrations of the mechanism connecting rod and walking beam, the time variation diagrams of the linear elastic displacement were obtained in the Maple programming environment. In order to confirm the theoretical results but also for a complex analysis of the entire pumping system, there was determined the force acting upon the polished rod and there were compared the values obtained by calculus and the values experimentally determined for the angle of rotation of the walking beam. Permanent monitoring of the pumping rod mechanical stress and vibration acceleration might contribute to more efficient operation of oil deep extraction wells.

Contributions Regarding the Energy Efficiency Increasing for a Hotel Building in order to Ensure a Healthy Indoor Environment

This paper purpose is to provide recommendations after a thermal energy analysis and inspection of a hotel building and its related facilities, in order to increase energy efficiency saving primary resources, to ensure a healthy indoor climate for users, and last but not least to ensure a reduction of CO2 emissions in order to ensure an external environment with low pollutant emissions. All the carried out analysis has as main objective to consider a symbiosis between all the parameters involved (energy, indoor/outdoor environment, comfort), when a building (envelope and installations) is renovated, especially when excess in order to save energy tend to endanger the indoor climate. Non-invasive methods were used to inspect the building by using thermo-vision both for the building envelope and for inspection of existing installations. The building utilities bills were analyzed for a period of one year to highlight current energy performance. The given recommendations achieve the proposed goal and highlight the active role of building management, continuous monitoring of energy and utilities to assess and improve energy efficiency, and ultimately to minimize specific energy costs. The results of this study can be used successfully on a wide range of hotel buildings in Romania.

Validation of GenEcAm Software Results in Simulation of Seismic Behavior of Buildings Equipped with Damping System

This paper presents the validation process of the GenEcAm program made by the author by comparing the results obtained with this program with the results obtained with the SAP2000 program at the dynamic analysis of a P+10E building equipped with viscous fluid dampers, one on each facade on each level. The results obtained with these two programs are very close, which validates the correctness of the analytical and computational model that underpinned the creation of the GenEcAm program. The GenEcAm program allows the use of 9 theoretical models of hysteresis to simulate seismic behavior of the dampers that equippe the structure of a building.

Active House - A Building that Offers more than Consumes

Active House is a vision on some buildings that create a healthy and comfortable life for their occupants without influencing in a negative way the climate and environment - leading to a cleaner, healthier and safer world. Active House proposes a target framework for changing the way we build and renovate buildings in order to contribute positively to our health, safety and well-being, focusing on indoor and outdoor environment and on the effective use of energy.

Theoretical and Experimental Study of the Human Upper Limb Dynamic Behavior

The paper presents the determination of the constraint forces acting in the human upper limb joints, using the inverse dynamic analysis procedure based on Lagrange multipliers method. The kinematics parameters time variation laws were established through experiments for the considered driving joints. The constraint forces time variation laws define the database for the dynamic analysis using the finite element method and for dimensioning an exoprosthetic system for later rehabilitation of the human upper limb motion.