Fatigue strength analysis considering temperature distribution [Improved high temperature strength analysis accuracy, faster meshing]

Motorcycle manufacturer

Fatigue strength analysis considering temperature distribution [Improved high temperature strength analysis accuracy, faster meshing]

A certain motorcycle manufacturer has been working on improving the analysis accuracy of high temperature strength in order to respond to the tightening of exhaust gas regulations, and speeding up meshing to respond to the increase in the number of CAE studies. Jupiter-Pre, Post and Sun Shine are used for high temperature intensity analysis, and Jupiter-Exhaust Modeling is used for meshing.

Client	Motorcycle manufacturer
Purpose 1	Improved analysis accuracy of high temperature strength
Purpose 2	Reduction of mesh model creation man-hours
model	Exhaust system
mesh	Shell element (some solid elements)
analysis	Temperature-dependent fatigue strength analysis (in cooperation with mechanical analysis)

background

Correspondence to improvement of strength and durability at high temperature due to tightening of laws and regulations.

Lightness and design are important for the exhaust system parts of motorcycles, and various metal materials are used. On the other hand, due to the recent tightening of environmental regulations, the temperature of exhaust gas tends to rise, and it is necessary to select a material with appropriate durability and strength. Therefore, the demand for design study by CAE is increasing, but since the exhaust system is a downstream process, it is necessary to study in a short time. Against this background, an analysis method with high prediction accuracy and execution in a short time has been desired.

Solution

Development of fatigue treatment by Jupiter and introduction of meshing for exhaust system.

Therefore, in order to improve the accuracy of high-temperature strength analysis, we have established a method of mapping different material properties for each temperature with Jupiter and collectively performing fatigue treatment using multiple fatigue limit diagrams (thermal stress is the mechanism analysis software RecurDyn). We are seeking in cooperation with). As a result, the three factors of engine vibration stress-> thermal stress-> fatigue limit reduction are considered at the same time. In addition, we have established a new modeling flow with Jupiter-Exhaust Modeling (exhaust system meshing function) to speed up meshing and standardize operations.

effect

Improved analysis accuracy of high temperature strength and faster meshing (1/4 man-hours)

The new method improves the accuracy of predicting natural frequency, thermal stress, and factor of safety. In addition, many results from multiple temperature distributions and combinations of materials and properties can now be processed collectively by the fatigue limit diagram table function for each material temperature of Jupiter-Post. With the introduction and customization of Jupiter-Exhaust Modeling, meshing time has been reduced to about 1/4 of the conventional time.