Modal Analysis of Inertia Dynamometer by using FEA

摘要

The Dynamometer is a LOAD device. It applies a load to an engine so we can test the performance of the engine under a variety of circumstances. System operates where load (dyno) torque equals that of the engine. By varying the engine throttle and load we can test any point under the engines max. torque curve. We design and modify engines for improved fuel economy and emissions. So, to study the vibrations due to resonance of dynamometer by modal analysis. In this paper, we are operated Inertia dynamometer at 1000 rpm to generate the necessary inertia. For different kind of conditions, there is need of having variable inertia so, constructed Inertia dynamometer with fixed flywheel having weight 1340kg initially and finding the natural frequencies at three different mode shapes. Also, the inertia dynamometer is constructed with fixed and removable flywheel having weight 1340kg and 7000kg respectively, again finding natural frequencies at three different mode shape by using FEA. We want to prove, natural frequencies for both above conditions much higher than operating frequency of dynamometer to avoid resonance caused vibration and failure of dynamometer. Also, we are trying to show if load and inertia increases the natural frequencies decreases for three different mode shapes respectively in comparison by keeping same conditions except load. Finite Element Analysis (FEA) tools allow engineers to design product and to simulate these designs for residual stress, structural response, pre-processing and post processing fatigue and similar effects on the machine component. FEA allows engineers to load the component at its extreme conditions and simulate its response or otherwise it is not possible to do it because of safety limitations of cost consideration.FEA helps to analyze for crash simulation, creep and fatigue test on virtual component leading to reduction in time consuming trial and error procedure for design the prototype and it also helps to reduce the cost of manufacturing. The leading manufactures have accepted simulation as a part of early design process with prototyping and testing are done to ultimately verify the designs.