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In order to study flow induced convective and acoustic pressure fluctuations around a car side window and their transmission characteristics and mechanism to the interior, a full-size DrivAer clay model equipped with a normal front left side glass was employed. In this way, the side glass is the exclusive transmission path for the exterior pressure to the isolated acoustic cabin behind the glass. By means of a compressible CFD simulation based on the Spalart-Allmaras DES model combined with an improved wavenumber decomposition algorithm particularly implemented in MATLAB, the two kinds of pressure fluctuations on the side glass of DrivAer model were separated successfully. Subsequently, their contributions to interior noise were calculated with SEA method individually. Since the predicted total interior noise level at the middle and high frequency range shows good agreement with the tested result, the reliability of the implemented wavenumber filtering approach was indirectly validated. The contributions of these two fractions indicate that the acoustic pressure fluctuations take much higher transmission efficiency than the convective one, especially for frequencies above the coincidence frequency of the glass, the contribution of the acoustic fraction is even absolutely dominant.

Even though the noise issue in manufacturing is widely discussed from legal and health aspects, there is still no comprehensive method to simulate and analyze it. In this paper, a novel concept to investigate the noise level is proposed. Therefore a simulation method and the virtual reality (VR) implementation are involved. Acoustic measurements in real factory provide validation data for a realistic simulation. Furthermore, a representation of simulation results in the virtual environment is visualized in a Cave Automatic Virtual Environment (CAVE). The analysis and evaluation of potential noise reduction are realized by using described methods.

We present a novel method to simulate fibers in flows transporting droplets. We discuss how to model the collisions of droplets and fibers. Since droplet-fiber collision is computationally expensive we use a new stochastic approach modeling the collision probability of droplets and fibers. From a continuous spatial distribution of the particle masses we can calculate the impact on a specific fiber at any arbitrary point. This gives an average mass and momentum of the droplets which is transferred to the fiber. We integrate our model in a fiber dynamics simulation tool (FIDYST) used to simulate industrial manufacturing processes.

Insertional leukemogenesis represents the major risk factor of hematopoietic stem cell (HSC) based gene therapy utilizing integrating viral vectors. To develop a pre-clinical model for the evaluation of vector-related genotoxicity directly in the relevant human target cells, cord blood CD34(+) HSCs were transplanted into immunodeficient NOD.SCID.IL2rg(-/-) (NSG) mice after transduction with an LTR-driven gammaretroviral vector (GV). Furthermore, we specifically investigated the effect of prolonged in vitro culture in the presence of cytokines recently described to promote HSC expansion or maintenance. Clonality of human hematopoiesis in NSG mice was assessed by high throughput insertion site analyses and validated by insertion site-specific PCR depicting a GV typical integration profile with insertion sites resembling to 25% those of clinical studies. No overrepresentation of integrations in the vicinity of cancer-related genes was observed, however, several dominant clones were identified including two clones harboring integrations in the ANGPT1 and near the ANGPT2 genes associated with deregulated ANGPT1- and ANGPT2-mRNA levels. While these data underscore the potential value of the NSG model, our studies also identified short-comings such as overall low numbers of engrafted HSCs, limited in vivo observation time, and the challenges of in-depth insertion site analyses by low contribution of gene modified hematopoiesis.