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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.

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.