Optimising Transmission NVH with CAE
The Benefits of Improving NVH
- Meeting legislation: legislation exists in most markets to set maximum limits for noise and vibration. This can be for pass by noise or to meet working environment directives. If products don’t meet the legislative targets they will be prevented from selling or will incur a fine.
- Increasing sales: demand for a product will be increased by optimising the NVH. This can be through reducing overall NVH levels or achieving the appropriate sound for your brand e.g. a high performance versus a luxury vehicle. This increased demand can be turned into increased unit sales or margins or a combination of the two.
Challenges to Maintaining or Optimising Transmission NVH
- Changing performance targets: the transmission or component will be in a constant state of development to improve one or more of the following: efficiency, torque capacity, weight, cost, size.
- New applications: the engine will be tried in different applications to increase sales volumes either within or across industry segments for example passenger vehicle to small commercial vehicle or across industries for example stationary (power generation) to automotive or automotive to marine.
- New environments: the engine may be sold in different geographical markets to increase sales. These may have significantly different operating temperatures, air densities (altitude) or air compositions (pollution) than the home market.
- New duty cycles: new customers may introduce more severe usage patterns for example the police or military environment
The Importance of Design Verification using CAE
Whenever a design is changed, for whatever reason, it is essential that the product is tested either physically or virtually to determine whether those changes have had a negative effect on its NVH performance. For example a weight reduction exercise can reduce the stiffness of the casing which may increase its vibration. This outcome can be minimised through good design based on a solid understanding of NVH fundamentals.
As discussed in the Transmission page CAE simulation allows the engineer to verify relatively quickly and cheaply whether the revised product still meets its NVH targets. To read more about the benefits of CAE click here.
When optimising NVH is the main design objective then CAE simulation can be performed to check any negative consequences on any of the other attributes including durability, weight, thermal, efficiency and torque capacity. For example modifying gear micro-geometry to reduce noise can reduce the efficiency which will lead to lower fuel economy. Again this outcome can be mitigated through good design based on a solid understanding of NVH fundamentals and advanced problem and product specific simulation tools.
The Caepro Advantage
Caepro has performed NVH CAE on the major components of the transmission both individually and as an assembly. This includes rattle and whine. See one of our Transmission NVH Case Studies. Our deep product knowledge and experience enables us to
- Understand your objectives for the product
- Prepare a model optimised for calculation speed and accuracy
- Apply appropriate boundary conditions
- Perform simulation using world-class procedures and tools
- Make sensible recommendations for design improvements
- Minimise any negative impact on other attributes
To get more information or to request a quote for transmission NVH CAE please submit an enquiry. For more on why Caepro is the best partner for your outsourced CAE requirements please read our 9 Reasons for Using Caepro article.