*Article* **Significance of Model Parameter Variations in the pARD-RSC Model**

#### **Armin Kech 1,\*, Susanne Kugler 1 and Tim Osswald 2**


Received: 10 July 2020; Accepted: 29 July 2020; Published: 7 August 2020

**Abstract:** This study aims to evaluate how fiber orientation results are dependent on fluctuations in input parameters, such as the average fiber length, fiber volume content, and initial alignment of fibers. The range of parameters is restricted to deviations within one specific short fiber reinforced thermoplastic and is not set up to investigate the di fferences between materials. The evaluation was conducted by a virtual shear cell based on a mechanistic modeling approach. The fiber orientation prediction model discussed is the pARD-RSC (principal anisotropic rotary di ffusion-reduced strain closure) model implemented as a user routine in AUTODESK MOLDFLOW INSIGHT ® (AMI ®). The material investigated was discontinuous short glass fiber reinforced PBT (polybutylene-terephthalate), which is often used for housings in various industries. It is shown that variation in the input parameters, although having an influence on the fiber orientation model parameters, only a ffects the final orientation moderately.

**Keywords:** pARD-RSC; fiber orientation; short fiber reinforced; mechanistic modelling
