Optimizing Heating Boiler Acoustics at Viessmann with Altair OptiStruct

• Procurement
• Product Research & Development

• Traffic Monitoring

Viessmann Werke GmbH, a leading manufacturer of household and industrial heating technology, was faced with acoustical issues during the development of a new generation of gas-fired heating boilers. The challenge was to reduce the noise levels by increasing the structural stiffness of the boiler cover. The initial approach involved integrating additional parts to increase the stiffness. However, this method was not optimal as it resulted in increased mass and more parts, leading to higher costs. An alternative approach was sought, which led to the exploration of optimum bead patterns using Altair OptiStruct. The bead pattern concept was preferred as it resulted in less mass, fewer parts, and ultimately, a lower total cost.

Viessmann Werke GmbH is a leading manufacturer of household and industrial heating technology based in Germany. The company is committed to minimizing environmental impact at every stage of the manufacturing process chain through the use of innovative product designs. During the development of a new generation of gas-fired heating boilers, the company faced a challenge with acoustical issues that needed to be resolved through design changes to the boiler cover. The company sought a solution that would not only resolve the acoustical issues but also be cost-effective and environmentally friendly.

To generate the best possible bead pattern, a two-step optimization process was employed using Altair OptiStruct. The first step involved topography optimization to generate the initial bead layout. The desired bead parameters, such as bead width and height, were defined within the design space. OptiStruct then generated a design proposal for the optimum pattern with respect to given design targets. The goal was to maximize the stiffness of the cover under specified load conditions. OptiStruct also allowed for the definition of desired bead pattern symmetries to generate designs that are easier to manufacture. The second step involved shape optimization of the pre-optimized bead pattern to further improve component performance. Integrated morphing technology was used to parameterize the initial design for shape optimization, even without underlying CAD data.

• The optimized cover design for the 'Vitopend 200' boiler series, enhanced by Altair OptiStruct, went into production in 2005. The use of optimization techniques in the design process led to significant improvements. The stiffness of the boiler cover was increased, which effectively reduced the noise levels. Additionally, the bead pattern concept resulted in less mass and fewer parts, leading to a lower total cost. The design was also easier to manufacture due to the defined bead pattern symmetries. The successful implementation of this solution demonstrates the potential of using advanced optimization techniques in the design process to improve product performance and reduce costs.

• Stiffness improvement of the cover: +20% compared to the alternative design concept
• Part consolidation and cost reduction: ~30% (an assembly of 4 parts reduced to one)