LMS Test.Lab Transfer Path Analysis

Transfer Path Analysis or TPA is used to identify and assess structureborne and airborne energy transfer routes – from the excitation source to a given receiver location. Once the sources and their paths have been quantifi ed and modeled, it is a relatively straightforward design task to optimize the system. Transfer path analysis sets out to quantify the various sources and their paths and fi gure out which ones are important, which ones contribute to the noise issues and which ones cancel each other out.

The LMS Test.Lab Transfer Path Analysis solution is based on the source-transmitter-receiver methodology. All noise and vibration issues originate at a source and are transmitted through airborne or structure-borne transfer paths to a given receiver location where the vibro-acoustic disturbances are perceived. Solving vibro-acoustic issues can be done by acting on the source, the transmission path or the receiver, or by addressing several of these elements. The goal of transfer path analysis is to calculate the vector contribution of each energy path from the source to the receiver. Components along that path can be identifi ed and thus modifi ed to solve a specific problem. Alternatively, TPA helps optimize the product design by choosing effective and desirable characteristics for these components to avert noise and vibration problems.

LMS Test.Lab Transfer Path Analysis is designed to manage data collected during measurement campaigns in a convenient and effi cient way. Using embedded documentation, like function class or point IDs, transfer functions and operational data are automatically sorted through easy transfer path model defi nition. The automated procedures eliminate data handling errors and make the process as
productive as possible.。

Similar processing can be simultaneously applied to different operating conditions. For engine transfer path analysis, engineers will typically prefer to analyze the most important orders during run-up or run-down. Working on spectra in different formats (spectrum, autopower, 1/3 octave) is also completely supported by the solution.

LMS Test.Lab Transfer Path Analysis focuses on ease-of-use and productivity. Engineers appreciate the workfl ow-oriented GUI, the powerful data management that continuously checks data and minimizes translation issues and operator errors. The productivity enhancing features like active displays make it possible for any person in the organization to dive into the data and investigate it from all possible angles to achieve the best understanding of the TPA results.

LMS Test.Lab Transfer Path Analysis helps users perform data processing and results interpretation fast and effi ciently. The enormous amount of TPA results is easily accessibly and clearly organized. For each operational condition and transfer path, the operational forces can be retrieved and accessed. To quickly visualize the relative importance of the different paths, a color display shows the amplitude of the partial contributions for all selected paths as a function of rpm or frequency.

The LMS solution helps users analyze the interior acoustic response both objectively and subjectively and identify the disturbing spectral components or even the lack of masking constituents. For those frequencies, the operating and laboratory data are combined to quantify the contributions of the various sources and their paths. Once the sources and their paths have been quantifi ed and modeled, it is a relatively straightforward design task to optimize the system.

The various TPA techniques can be expanded to support “what-if” scenarios, whereby loads and/or transfer paths can be interactively modifi ed and visually evaluated in real-time. Multiple modifi cations can be compared against each other, by a single mouse-click, which
greatly enhances the target setting process.