• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.8
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• pp.773-780
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• 2009

The facility equipments generate dynamic force on building floor and the force can be measured with force transducer. However, this method depends on the measuring capacity or range of sensor, or mounts installation condition of equipments. Because of this restricting condition on force measuring system, this paper suggests a indirect method, the TPA(transfer path analysis) method, that produces a closely approximate dynamic force of equipments. This method calculates the dynamic force by using transfer response function. Firstly, the calculated dynamic force of impact load and continuous load was respectively compared with the sensor-measured value to examine the accuracy of TPA method. After that, the dynamic force and response induced by large facility equipments - a cooling tower, AHU and a large ventilator - were calculated by TPA method and the validity of these value were examined.

• Journal of KSNVE
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• v.8 no.6
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• pp.1158-1165
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• 1998

Low frequency interior noise in cars is mainly due to structure-borne excitations which are related with road excitation and component vibrations such as suspension and engine mounts. In order to analyze the annoying interior noise. a technique (Transfer Path Analysis) is introduced to find a noise source and the path of that noise. In this study, TPA is reviewed theoretically and applied to investigate the case when the low frequency interior noise at front seat due to road excitations needs to be optimized. The subjective and objective appraisal was performed under the conditions that a testing vehicle traveled on asphalt at 30 km/h. so that the low frequency to be eliminated was detected. The related vibration and noise data for TPA were measured on running and static vehicle. The results reveal that the noise contribution along the z-direction of trailing arm is prominent to low frequency interior noise.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.12
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• pp.107-116
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• 2008

The excitation force of a powertrain is one of major sources for the interior noise of a vehicle. This paper presents a novel approach to predict the interior noise caused by the vibration of the power rain by using the hybrid TPA (transfer path analysis) method. Although the traditional transfer path analysis (TPA) is useful for the identification of powertrain noise sources, it is difficult to modify the structure of a powertrain by using the experimental method for the reduction of vibration and noise. In order to solve this problem, the vibration of the power rain in a vehicle is numerically analyzed by using the finite element method (FEM). The vibration of the other parts in a vehicle is investigated by using the experimental method based on vibrato-acoustic transfer function (VATF) analysis. These two methods are combined for the prediction of interior noise caused by a power rain. Throughout this research, two papers are presented. This paper presents a simulation of the excitation force of the power rain exciting the vehicle body based on numerical simulation. The other paper presents a prediction of interior noise based on the hybrid TPA, which uses the VATF of the car body and the excitation force predicted in this paper.

• Journal of Drive and Control
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• v.13 no.1
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• pp.72-77
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• 2016

• Journal of Drive and Control
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• v.16 no.2
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• pp.1-7
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• 2019

Jaw crusher is a device that breaks rock collected from mines or quarries to produce aggregates of the size desired by user. A representative method for measuring load is to measure them by attaching force sensors directly to the part where the load is generated. However, the direct method has many limitations such as high-impact loads generation in equipment or space constraints, sensor capacities and costs. Therefore, Transfer Path Analysis (TPA) was used to indirectly measure impact loads by attaching acceleration sensors. In this study, both direct and TPA methods were used to measure the impact load of Jaw crusher. This study finally quantifies the impact of the load generated by the Jaw crusher using direct method and TPA method, and comparing the impact load measured calculated the derive the error rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.1
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• pp.46-52
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• 2012

A PAEM(Pneumatic Active Engine Mount) system has been developed to improve NVH performance of a SUV in idle state. Control objective to attenuate the vibration of a vehicle should be determined prior to the design of control algorithm. This study presents the correlation analysis of output variables of PAEM system by means of TPA(Transfer Path Analysis) using experimental data obtained by vehicle test. The analysis results show that the vibration of vertical direction is more serious than those of longitudinal and lateral direction of the vehicle, and that the correlation between the vibration of front seat rail and that of steer wheel is highest. In conclusion, the vibrations of front seat rail and steer wheel in vertical direction should be considered as the control objectives of the PAEM.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.365-370
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• 2011

Structure-bone noise is an important aspect to consider during the design and development of a vehicle. Reduction of structure-bone noise of the compartment in a vehicle is an important task in automotive engineering. Many methods which analyze transfer path of noise have been used for structure-bone noise. The existing method to measure of frequency response function of transfer path has been tested by removing a source. This Paper presents an experimental analysis about Transfer Path Analysis of the vehicle interior noise according to Excitation or not. To identify these points of difference, experiment were conducted through an experimental test using simulation vehicle.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.452-457
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• 2008

In this paper, the vibrations of floor systems of which buildings are under construction are studied by experimental and analysis method. The first step is to measure the operational response data and FRF at the supporting points of the utility and the second step is to calculate the dynamic load by TPA Method which provided by LMS VirtualLab System Analysis Module. The dynamics we used to identify is expressed by below equation; $$\{F_{oper}\}=[H]^{-1}\;{\cdot}\;\{{.. \atop x_{oper}}\}$$ Where, H(Transfer function between position of the force and response) and x(response) are measured by vibration test.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.05a
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• pp.123-125
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• 2010

As the exterior noise emitted by a vehicle is getting more and more attention, simulated pass-by measurements become more important. This well established method provides information about the total noise emitted by the vehicle. For a vehicle manufacturer it is not only interesting to know about the total noise but also to know how this total exterior noise is composed of different contributions, such as for example the contribution of the engine, the intake or exhaust system. Transfer path analysis (TPA) provides a separation of these contributions for each of the pass-by microphones alongside the track. Presented is a method for fast and efficient determination of the contributions of multiple sources using operational transfer path analysis (OTPA). The calculation of the transfer characteristics between the reference measurement points on the vehicle and the corresponding response points of both microphone lines are carried out while operation of the vehicle. As result of the contribution analysis from operational transfer path analysis, the characteristic noise level as function of the covered distance is displayed for all individual sound sources, thus providing in depth information for sound quality engineering.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.822-823
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• 2013