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The use of dynamometers, especially inertial ones, has been widespread in Brazil in recent years. This increase in the use of the tool has several reasons, among them the greater availability of equipment, price reduction and the appearance of programmable electronic injections. Programmable injections, for better engine performance, must be adjusted in the different conditions of use and in the different points of the injection and ignition maps. This adjustment could be made by driving the vehicle on streets or in a proving ground, however the torque and power gain cannot be measured with sufficient precision to decide the ideal ignition timing and injection time. The inertial dynamometers marketed in the country, and used in repairers or vehicle preparers always bring software that allows the acquisition and registration of the information obtained in the tests.

This article presents the dynamic modeling of a three-cylinder engine, known in the literature for high levels of vibrations due to equilibrium conditions. The engine and gearbox assembly were modeled as a rigid element with 4 degrees of freedom (DoF), these being displacement and rotation around the X and Z axes. In the presented study, it was calculated the dynamic responses of two support cushions of the engine, having as excitation the inertial forces related to the reciprocating movement of the pistons and connecting rods, and unbalance of the crankshaft counterweights. The results obtained with the mathematical model were compared with measured data of first order vibration of the engine rotation. Tests were performed at full throttle, WOT condition, in third gear.

Integrated controls for commercial dynamometers do not have appropriate characteristics to perform research and teaching tasks. These are developed to perform quick tests and its logic is prepared to obtaining the information in accordance with the technical standards. This way, the use for research is hindered because it does not have an interface that allows a refinement to the desired data ranges, t data sampling and the type of load that is applied. Its use for teaching is limited because these "standard" controls does not allow to analyze or to determine engines characteristics that are not covered through tests specified by the standards, so the use of this tool as an important part in professional training formed by the institution.

Conventional airflow benches do not measure the swirl airflow effect, being restricted to indicate the flow for a given test pressure. This effect directly affects the volumetric efficiency of the engine and, therefore, the performance and fuel consumption of the vehicles. The behavior of swirl in the intake airflow improves the filling capacity of the combustion chamber, homogenizes the air fuel mixture and improves the fuel combustion efficiency, enabling the engine to deliver more power in the same cycle. This paper describes the development of a swirl measurement system to be adapted to conventional flow benches offered on the market, which can be also applied in other tests where the flow swirl effect is important.

In a test bench for automotive shock absorbers the angular velocity of the "scotch yoke" mechanism must be constant, but the load (resulting from shock forces) varies in function of the speed, resulting in fluctuations in the speed along the course of the test, in function of the frequency variator response time controlling the electric motor. Employing a closed loop control system for the automotive shock absorber tests will result in tests with better quality at higher speeds and loads, thus enabling a better representation of the shock absorber condition. The paper presents the state of the art and research in development that is linked to closed loop control mechanisms. It is developed a control system which allows maintaining a constant test speed, independent of the load reaction to a range of shock absorber tested, as a function of resultant load. The mathematical modeling of the problem is presented, quantifying the magnitudes involved.

The compression springs of the valves of automotive engines are key elements in the dynamic behavior of the engine. Its wear is slow, gradual and progressive; so the driver of the vehicle eventually get used to the decrease in the engine performance. The compressive force losses cause the valves to close slower than expected and, consequently, the engines lose their efficiency. Professionals in the area of automotive maintenance apply empirical tests with varying criteria to evaluate and to determine the life cycle end at which the springs must be replaced. This article describes the development of a workbench for compression springs based on existing models on the market and the main premise is the low cost. Correspondent loads involved were determined and the components were modeled in CAD, allowing to develop a robust device able to handle the loads generated by the compression spring.

The analysis of pressure losses in the cylinder head of an engine, which can compromise up to 70 % of engine efficiency is accomplished by a device called a flow bench, to evaluate the variation in flow and pressure between the inlet and outlet of the cylinder by reading in measurement instruments typically water column manometer. The paper describes the methodology used in the automation of a flow bench. A printed circuit containing pressure transducers (absolute pressure sensor to intake manifold) that send electrical to a microcontroller (Arduino) signals and is shown on an interface card was drawn. For temperature we opted for the use of a digital sensor with smaller margin of error for the same price (compared to analog sensor). The level of the valve is done by a digital caliper. In man machine interface are indicated test pressures and the percentage of flow, temperatures at admission and exhaust are indicated as well as the calibrated orifices are open.

Automotive shock absorbers are key elements in the dynamic behavior of vehicles. Their degradation is slow, gradual and progressive, so that the driver of the vehicle eventually gets used to the decrease of the damper's performance without noticing it. This article describes how a test bench was developed based on existing market models, however having as its main goal the low cost of production. The Crankshaft and Scotch Yoke mechanisms were studied in an analog way and simulated in CAD software. After this analysis the Scotch Yoke system was chosen because its motion describes a perfect sine function. To drive the system it was used a 5HP electric motor, and a frequency inverter to control the motor's speed with capability of 7.33A, allowing the device to have the ability to test not only production line vehicles but also competition dumpers.

This paper aims to improve a device, installed in the Laboratory of Engines at the Instituto Federal de Santa Catarina (IFSC), used by students and professors for classes and researches of ADeMCI (Performance Evaluation of Internal Combustion Engines) research group registered on CNPq. This paper presents the development of an automated flowbench for test cylinder heads using electronic features as MAP (manifold absolute pressure) and MAF (manifold air flow) sensors, commonly used in automotive systems to control the fuel injection in engines. Automated flowbenchs already exist in the international market, but their costs are expensive for the acquisition. This kind of device allows a cylinder test to be executed in a short time, with greater accuracy readings without the direct influence of the operator's ability. The automation of a flowbench like this will increase the capacity of testing of the laboratory, allowing to train more students and to develop more researches.

The purpose of this project is to develop and test a technological adaptation in an internal combustion engine to increase its efficiency and the reliability of its system of monitoring and measurement of power. Such engines are used as propellants in reciprocating compressors of natural gas (NG) in compression stations installed in the company TBG S/A (owner and operator of the Bolivia Brazil Pipeline). These compression stations receive NG at a pressure of up 58kgf/cm2 and compress natural gas at a pressure of up 75kgf/cm2. Currently the measurement of power expended by the compressors that compress the NG does not happen precisely; this measurement is an important parameter for the operation of the equipment. After studies, it was found that this lack of precision is one of the factors that sometimes cause the operation of compressors off the power range recommended by the engine manufacturer.

In internal combustion engines, gas exchange in the combustion chamber through the intake and exhaust are directly related to engine efficiency. The mechanical element responsible for handling and synchronization of the valves during cycles of intake, compression, combustion and exhaust, in Otto cycle engines and diesel cycle is the camshaft. Soon to know the characteristics of lift, duration, crossing, and the characteristics of velocity and acceleration of the valve assembly is very important to assess the performance of internal combustion engines. However, the engine manufacturers do not provide such features accurately, in order to avoid being easily modified or acquired by other manufacturers. And subtle changes between camshafts fitted the same engine family may promote different torque characteristics and power consumption as well as without, however, characterize a new engine.

The paper addresses the development of an electromagnetic brake control and data capture of torque and rotation, using a graphical interface implemented in LabVIEW for evaluating the performance of internal combustion engines. To control the electromagnetic brake is used like a SMPS Buck, and programming interface developed in LabView is responsible for generating the pulses of voltage that feeds the brake and the data capture system. This project started with the need for improved equipment control and data acquisition dynamometers, eddy-current, installed at the Automotive Laboratory, Instituto Federal de Santa Catarina (IFSC). In the system of control and data acquisition parameters can be added as temperatures, pressures etc., further improving the precision of torque and power these devices.

The paper addresses the development of an electromagnetic brake control and data acquisition system to capture speed and torque. LabVIEW™ was used to implement a graphical interface to evaluate the performance of internal combustion engines. This graphical interface allows processing and displaying the signs in their appropriate units, and also the refinement of data in the desired tracks, in ways to evaluate the power and torque curves. This project started with the need to improve research equipment control and data acquisition on eddy-current dynamometers that are installed in the ADeMCI research group of the Instituto Federal de Santa Catarina (IFSC). In the control system and data acquisition parameters other variables can be added, such as temperatures, pressures, etc., this will promote further improvement in the precision of torque and power reading with this device.

The aim of this article is to diagnose the level of emission of gases, responsible for the Greenhouse Effect, in the vehicles that are in circulation in the area of the Great Florianópolis and to propose a methodology of obligatory vehicular inspection for the fleet, in regular intervals that may be responsible the reduction of the values of emission of these vehicles. For that it was collected and analyzed a database containing 1117 vehicles, of these, 97 were reproved in the regular tests of emissions, becoming the study object for the development of the research.