| 1. |
- Brett, Calvin
(författare)
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Neutron and X-ray Surface Scattering Reveals the Morphology of Soft Matter Thin Films
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The last decades have been overshadowed by reports about the seemingly endless increase use of fossil-based resources. With the development of new products, our mindset is changing so that we more and more need to consider sustainability in our daily lives. Furthermore, smarter devices are indispensable in our world and daily life, and these are expected to be smaller and smaller in size.To support the transition from fossil-based to sustainable materials, we need to develop knowledge of new materials. Within this thesis project, the aim has been to understand the thin-film properties of sustainable materials and to develop methodologies to measure these. As sustainable template material wood-based nanocellulose was chosen as a bio-degradable representative with favourable favourable physical properties, such as lightweight, transparency, and flexibility. These properties make nanocellulose a perfect candidate for future advanced applications in thin-film organic solar cells, supercapacitors, or sensors. Nanocellulose comprises only a part of such a device, and hence the relevant functional materials and their combinations have to be studied to reveal the interaction between multiple material components on the final device performance. As the nanoscale, or even Ångstrom scale, governs the macroscopic physical properties, it is crucial to understand the materials in detail. Ergo, neutron and X-ray surface-sensitive scattering methods were applied to study nanoparticle deposition layering kinetics and the effects of environmental changes, which revealed the morphology of the resulting nanoporous nanocellulose thin films. The knowledge was used to infiltrate water-soluble intrinsic conductive polymers into these nanopores, which serves as a model for transparent but conductive templates for organic electronics. By changing the environment of the films through humidity cycling, the impact of the environment during a real-life application could be illustrated. Neutron scattering experiments also showed that the cellulose-conductive polymer composite (or hybridmaterial) changes irreversibly during humidity cycling while the pure nanocellulose films show fully reversible properties.Furthermore, the thermal decomposition of silver nitrate deposited on nanocellulose was studied to understand the nanofibrils' impact on the synthesis of nanoparticles. The transparency allowed in situ studies of the synthesis process, the spectroscopic properties as well as the plasmonic effect, which demonstrated routes for minimal material usage concepts for surface synthesis processes. It was also discovered that the process allows for band-gap tuning, which can be directly be applied in organic solar cells to tailor the band-gap to be adapted and hence increasing the efficiency.The morphological properties, as studied using X-rays and neutrons, were correlated to macroscopic properties by measuring wettability, surface topography, spectroscopy, or conductivity to examine the full materials application possibilities. Neutron and X-ray scattering methods are complementary and wisely combined, thus allowed pioneering studies of bio-based sustainable nanocomposites leading to advanced functional material concepts that support the development of devices using less fossil-based materials.
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| 2. |
- Gullman-Strand, Johan, 1974-
(författare)
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Turbulence and scalar flux modelling applied to separated flows
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The turbulen flow in an asymmetric diffuser has been en studied by the means of Reynold average Navier-Stokes equations with both differential and explict algebraic expressions to model the Reynolds stress tensor. Modifications to the differential stress model have been derived, using the inverse turbulence timescale to obtain the dissipation of turbuence kinetic energy. The explicit algebraic Reynolds stress model has been used in combination with a two-equation platform to close the system of equations. Modifications made to the transport equation for the inverse turbulence timescale has made it possible to substantially relax the deman on near-wall resolution of this quantity. The rapid growth wth present in the original formulation can be treated as an explicit function of the wall-normal distance. In order to use the new formulation for the transport equation, an equation has as been derived to obtain the shortest distance bettwee a point and the closest wall, regardles of the geometric complexity of the domain. An explicit algebraic expression to model the passive scalar flux vector has been investigated using a comparison with a standard eddy-diffusivity model in the asymmetric diffuser. Results show a substantial improvement of the complexity of the scalar field and scalar flux vector in sepaarated flows. Automated code generation has been used in all the above studies to generate versatile model testing tools for general two-dimensional geometries. Finite element formulations are used for these tools.
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| 3. |
- Guo, Meng, 1988-
(författare)
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Hybrid Control of Multi-robot Systems under Complex Temporal Tasks
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Autonomous robots like household service robots, self-driving cars and dronesare emerging as important parts of our daily lives in the near future. They need tocomprehend and fulfill complex tasks specified by the users with minimal humanintervention. Also they should be able to handle un-modeled changes and contingentevents in the workspace. More importantly, they shall communicate and collaboratewith each other in an efficient and correct manner. In this thesis, we address theseissues by focusing on the distributed and hybrid control of multi-robot systemsunder complex individual tasks.We start from the nominal case where a single dynamical robot is deployed in astatic and fully-known workspace. Its local tasks are specified as Linear TemporalLogic (LTL) formulas containing the desired motion. We provide an automatedframework as the nominal solution to construct the hybrid controller that drives therobot such that its resulting trajectory satisfies the given task. Then we expand theproblem by considering a team of networked dynamical robots, where each robot hasa locally-specified individual task also as LTL formulas. In particular, we analyzefour different aspects as described below.When the workspace is only partially known to each robot, the nominal solutionmight be inadequate. Thus we first propose an algorithm for initial plan synthesis tohandle partially infeasible tasks that contain hard and soft constraints. We designan on-line scheme for each robot to verify and improve its local plan during runtime, utilizing its sensory measurements and communications with other robots. Itis ensured that the hard constraints for safety are always fulfilled while the softconstraints for performance are improved gradually.Secondly, we introduce a new approach to construct a full model of both robotmotion and actions. Based on this model, we can specify much broader robotic tasksand it is used to model inter-robot collaborative actions, which are essential for manymulti-robot applications to improve system capability, efficiency and robustness.Accordingly, we devise a distributed strategy where the robots coordinate theirmotion and action plans to fulfill the desired collaboration by their local tasks.Thirdly, continuous relative-motion constraints among the robots, such as collision avoidance and connectivity maintenance, are closely related to the stability,safety and integrity of multi-robot systems. We propose two different hybrid controlapproaches to guarantee the satisfaction of all local tasks and the relative-motionconstraints at all time: the first one is based on potential fields and nonlinear controltechnique; the second uses Embedded Graph Grammars (EGGs) as the main tool.At last, we take into account two common cooperative robotic tasks, namelyservice and formation tasks. These tasks are requested and exchanged among therobots during run time. The proposed hybrid control scheme ensures that the real-time plan execution incorporates not only local tasks of each robot but also thecontingent service and formation tasks it receives.Some of the theoretical results of the thesis have been implemented and demonstrated on various robotic platforms.
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| 4. |
- Johansson, Anna L V
(författare)
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Pregnancy and breast cancer : risk patterns, tumour characteristics and prognosis
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Pregnancy-associated breast cancer (PABC) is commonly defined as a breast cancer (BC) diagnosed during pregnancy or within one or two years after delivery. The risk of BC is lower than expected during pregnancy with a small rebound within 2 years after delivery, compared to non-pregnant women of the same age. Although a rare event, there is evidence that women with PABC have a poorer prognosis compared to women with BC diagnosed not near a pregnancy (non-PABC). It is important to improve the understanding of underlying mechanisms and identify factors that may influence outcome, including the role of detection and tumour biology. The possible influence of pregnancy exposures on detection and tumour biology may be time-varying, with different effects during the pregnancy period compared to time windows further away from delivery. Since a transient risk has been reported 5-10 years post-delivery, it is also of interest to compare pregnancy-associated tumours to tumours diagnosed further away, say up to ten years, from delivery with respect to tumour biology and prognosis. Having a relative with breast cancer is an established risk factor for breast cancer, in particular at a young age. Women with a family history of breast cancer may be more likely to have pre-malignant breast cells at a young age, and could be more susceptible to pregnancy-related exposures, such as elevated levels of endogenous hormones. Study III assessed the risk pattern for breast cancer during pregnancy and up to ten years after delivery in relation to family history of breast cancer using a cohort of 3.5 million women aged 15-44 years identified in the Swedish Multi-Generation Register and the Swedish Cancer Register. In total, 15,548 women had a recorded BC diagnosis of which 1,208 were PABC. To reduce the comparison population and improve computational efficiency, a case-cohort design was utilised. The results showed that a family history of BC did not affect the risk pattern around pregnancy and up to 10 years post-delivery, indicating that pregnancy-related exposures do not interact with the familial pre-disposition for BC in these women. Results from several studies have suggested that BC tumours diagnosed around delivery have adverse tumour characteristics, such as advanced TNM stage and triple-negative subtype, but it remains unclear if adverse tumour characteristics can fully explain the worse prognosis in women with PABC. Studies II and IV assessed TNM stage in cohorts of patients diagnosed with BC during pregnancy and up to ten years post delivery using information from the Swedish Cancer Register for years 2002-2009 (study II) and the Swedish Breast Cancer Quality Register for years 1992-2009 (study IV). Study IV also assessed histological grade and tumour biology, such as hormone receptor status. The results showed that tumours detected during pregnancy and within one year of delivery were more often advanced, of high grade and hormone receptor negative (triple-negative and non-luminal Her2 positive subtypes) compared to nulliparous women. These associations were most pronounced in tumours diagnosed during the first six months post-delivery. In combination with the previously observed lower risk during pregnancy, these findings could reflect diagnostic delays, resulting in more advanced tumours at diagnosis, or a suppression of hormone responsive tumours around delivery. With the aim to investigate prognosis in women with PABC, two partly over-lapping cohorts of BC patients were identified in the Swedish Cancer Register for years 1963-2002 (study I) and in the Breast Cancer Quality Register for years 1992-2009 (study IV), including 1,110 and 778 women with PABC, respectively. The association between PABC and mortality was analysed using Cox regression and flexible parametric models. The results from study I and IV corroborated previous findings that women with PABC have a poorer prognosis compared to women with non-PABC. The mortality was highest in women diagnosed 0-6 months after delivery, and remained elevated up to eight years after diagnosis, in comparison to women diagnosed not near a delivery. However, following adjustment for tumour characteristics, the difference in mortality between women with PABC and women with non-PABC was attenuated and non-significant (study IV). These findings suggest that although PABC is associated with more advanced and aggressive tumours, the outcome is similar to that in women with non-PABC when taking tumour characteristics into account. For comparison, we also assessed tumour characteristics and prognosis in women diagnosed with BC 2-10 years after delivery (study IV). A transient risk of BC around 5-10 years after delivery has been reported previously. Compared to nulliparous women, women diagnosed 2-5 years post-delivery did not differ in tumour size, grade and ER status, but more often presented with spread to lymph nodes, negative PR status and non-luminal Her2 positive subtype. Women with BC diagnosed 2-5 years post-delivery also exhibited a poorer prognosis compared to nulliparous women, which remained significant after adjustment for T/N stage and hormone receptor status. These findings could indicate different mechanisms for risk, detection and prognosis in women diagnosed 2-5 years after delivery compared to women with PABC. In conclusion, the findings indicate that pregnant and lactating women exhibit different patterns of BC risk, tumour biology and prognosis compared to other pre-menopausal women with BC. The poorer prognosis observed in women with PABC can largely be explained by adverse tumour characteristics at diagnosis.
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| 5. |
- Johansson, Malin E V, 1971
(författare)
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The MUC2 mucin -A network in the intestinal protective mucus
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The intestine is covered by mucus that is the first line of defence of the epithelium. The main structural component of the intestinal mucus is the MUC2 mucin. This is a large glycoprotein with two long and heavily O-glycosylated mucin domains. Our studies of the biosynthesis have revealed that MUC2 forms large disulphide linked networks starting with C-C terminal dimers. In the late secretory pathway the N-terminal of MUC2 forms trimers within a core fragment resistant to trypsin cleavage. The MUC2 assembly creates an enormous network with an ability to resist protease degradation. It is important that the mucus is resistant to the intestinal digestive enzymes. In colon, the real challenge is to wield the large number of bacteria in the normal flora. Immune tolerance has been studied intensely, but the contribution of the mucus in the protective function has been neglected largely due to the technical difficulties to work with the large mucin glycoproteins. The mucus in colon is made up of two mucus layers. In mouse the inner mucus layer is 50 µm thick and firmly attached to the epithelium. This is a compact, insoluble and stratified mucus layer with a high Muc2 concentration. The firm layer is converted to a 100 µm, soluble, loose overlaying mucus layer that is expanded in volume by proteolysis. The mucus turnover is fast and in colon the luminal mucus layers are renewed in hours. The composition of the mucus was investigated by proteomics and was found to be similar in the two mucus layers, indicating a common source. One of the components identified, Fc gamma binding protein (Fcgbp) was shown by purification of the mucus in guanidinium chloride to be covalently attached to Muc2. The binding may be mediated by potential autocatalytic cleavage sites that generate new reactive C-termini in Fcgbp. The disulphide stabilized Fcgbp could thus be a cross-linker of the Muc2 network. Bacteria in colon were detected in the outer loose mucus layer by in-situ hybridization using a 16S rRNA general bacterial probe. This mucus is likely to be a good habitat for bacteria providing binding sites and energy. The inner compact firm mucus is impervious to bacteria, making it a protective barrier for the enormous bacterial load. The mucus is through this mechanism a part of the innate immunity to keep the homeostasis in colon. The protective function of mucus argues for that defects in the mucus can be a cause of inflammation. In fact, mice with the Muc2 gene disrupted do not produce mucus and develop spontaneous colitis. In these animals the epithelium is in direct contact with the colonic flora, bacteria enter deep into the normally sterile crypts and penetrate the epithelial cells. An overt immune reaction to the bacteria is an obvious cause of the inflammation. In wild type mice Dextran sulphate (DSS), a highly sulphated glucose polymer, is used to induce colitis and is the most common UC model. DSS exposure resulted in alterations in the mucus long before any signs of inflammation were observed. The inner mucus allowed bacteria to penetrate as early as after 4 h of exposure, with a massive bacterial penetration into the inner mucus after 12 h. The mechanisms behind this colitis model were not known until now when our observations suggest that a defect mucus layer is likely to have triggered the inflammation. The importance of the inner mucus for epithelial protection argues for defective mucus as a possible cause of ulcerative colitis.
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| 6. |
- Johansson, Ulf. S., 1970-
(författare)
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Clades in the "higher land bird assemblage"
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis summarizes the results of several phylogenetic studies of birds included in the “higher land bird assemblage” (Anomalogonatae sensu Beddard 1898). The phylogenetic analyses are primarily based on gene sequences obtained from the nuclear genome (exons of the c-myc and RAG-1 genes and an intron of the myoglobin gene). Monophyly of the “higher land bird assemblage” has previously been suggested based on the loss of the ambiens muscle in these birds. However, in agreement with other molecular studies, the results presented do not corroborate the monophyly of this group, although the tree is basically unresolved to due lack of statistical support (Bootstrap, parsimony jackknifing and Bayesian inference). Of the groups included in the “higher land bird assemblage”, Strigiformes (owls), Apodiformes (swifts and hummingbirds), Coliiformes (mousebirds), Trogoniformes (trogons), Piciformes (e.g., woodpeckers, barbets, toucans, puffbirds, jacamars) and Passeriformes (passerines) are supported as monophyletic, whereas Caprimulgiformes (e.g., nightjars, oilbird, and owletnightjars) and Coraciiformes (e.g., rollers, cuckoo-rollers, bee-eaters, kingfishers, hoopoes, hornbills) are not. Among the caprimulgiform birds, the owlet-nightjars (Aegothelidae) are found to be closer to the swifts and hummingbirds (Apodiformes) than to other caprimulgiforms. In addition, the results indicate that the cuckoo-roller (Leptosomatidae) is not associated with rollers and ground-rollers as suggested by some previous studies. Instead, the rollers and ground-rollers (Coracioidea) are probably sister group to a clade containing todies, motmots, kingfishers, and bee-eaters (Alcedini). Hoopoes, woodhoopoes, and hornbills are monophyletic (Bucerotimorphae). As in many previous analyses, the relationships between Strigiformes, Apodiformes, Coliiformes, Trogoniformes, Piciformes, Passeriformes, Leptosomatidae, Coracioidea, Alcedini, and Bucerotimorphae are unresolved, which could indicate that these groups underwent a rapid evolution, probably in the late Cretaceous – early Tertiary.
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| 7. |
- Karimi, Arizo, 1983-
(författare)
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Impacts of Policies, Peers and Parenthood on Labor Market Outcomes
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis consists of five self-contained papers.Paper 1 This paper analyzes the causal effect of the timing of first birth on highly educated women's career outcomes. To address the endogeneity of birth timing to labor market outcomes, I instrument the former with the occurrence of pregnancy loss before first birth. The results from OLS estimation suggest that a one-year delay of motherhood is positively associated with income and wages. However, 2SLS estimation instead indicates that a one-year delay has a significantly negative effect on both income and wages. The negative effects might partly be explained by child spacing: motherhood delay induces women to have the second child more closely spaced (but not fewer or more children altogether), and consequently to have a potentially longer consequtive parental leave. The same findings hold true when I employ an individual-fixed effects estimator based on panel data and no instrument, from which the results suggest a larger slope decline in the wage profile for "late" mothers compared to "earlier" mothers.Paper 2 This paper analyzes the relevance of spacing births for women's subsequent earnings and wages. Spacing births in longer intervals may allow women to re-enter the labor market between childbearing events, thereby avoiding expanded work interruptions and, in turn, reduce the negative effects of subsequent children. Based on arguably exogenous variation in birth spacing induced by pregnancy loss between the first two live births, the evidence provided in this paper supports this hypothesis and suggest that delaying second birth by one year, on average, increases the probability of re-entering the labor market between births. Moreover, spacing births are found to increase both labor market participation and labor income over an extended horizon after second birth. Also long-run wages are positively affected, with a more pronounced effect for highly educated mothers.Paper 3 This paper studies gender differences in the extent to which social preferences affect workers' shirking decisions. Using exogenous variation in work absence induced by a randomized field experiment that increased treated workers' absence, we find that also non-treated workers increase their absence as a response. Furthermore, we find that male workers react more strongly to decreased monitoring. In addition, our results suggest significant heterogeneity in the degree of influence that male and female workers exert on each other: conditional on the potential exposure to same-sex co-workers, men are only affected by their male peers, and women are only affected by their female peers.Paper 4 We examine the temporal pattern of the causal effect of fertility on female labor income using panel data based on Swedish registers, and instrumenting family size with parents' preferences for a mixed-sex sibling composition. The effect of a third child over the life cycle is evaluated against the alternative of stopping at two children. Our findings indicate a sizeable income reduction in the immediate years after birth, followed by a catching-up effect in income. The short-lived reduction likely corresponds to formal parental leave. Gauging the magnitude of the effect, we find that income decreases by roughly 11 percent over a 10-year horizon after birth. No effects are found on long-run wage rates or on contracted hours of work.Paper 5 This paper re-examines the labor supply responses to changes in the Swedish parental leave system, recognizing that take-up of parental leave benefits might not fully reflect time off from work in a system where job protection exceeds paid leave. We study three reforms, of which the first expanded the entitlement to paid leave by three months, and the two other reforms introduced gender quotas in paid leave. We find that both mothers and fathers decreased their labor supply when entitlement to paid leave was increased. However, the additional benefits were spread out over a long horizon and thus seem to have been used by parents to increase job flexibility. In addition, we find no evidence suggesting that the introduced gender quotas in paid leave altered parents' labor supply.
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| 8. |
- Marstorp, Linus, 1978-
(författare)
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Modelling of subgrid-scale stress and passive scalar flux in large eddy simulations of wall bounded turbulent flows
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of the thesis is to develop and validate subgrid-scale models that are relevant for large eddy simulations of complex flows including scalar mixing. A stochastic Smagorinsky model with adjustable variance and time scale is developed by adding a stochastic component to the Smagorinsky constant. The stochastic model is shown to provide for backscatter of both kinetic energy and scalar variance without causing numerical instabilities. In addition, new models for the subgrid-scale stress and passive scalar flux are derived from modelled subgrid scale transport equations. These models properly account for the anisotropy of the subgrid scales and have potentials wall bounded flows. The proposed models are validated in wall bounded flows with and without rotation and show potential or significantly improve predictions for such cases.
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| 9. |
- Montecchia, Matteo, 1990-
(författare)
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Numerical and modelling aspects of large-eddy and hybrid simulations of turbulent flows
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this study, the explicit algebraic sub-grid scale (SGS) model (EAM) has been extensively validated in wall-resolved large-eddy simulations (LES) of wall-bounded turbulent flows at different Reynolds numbers and a wide range of resolutions. Compared to eddy-viscosity based models, the formulation of the EAM is more consistent with the physics and allows to accurately capture SGS anisotropy,which is relevant especially close to walls.The present work aims to extend the validation of the EAM to larger Reynolds numbers using codes with different orders of numerical accuracy.The first simulations, performed by using a pseudo-spectral code, show that the use of the EAM, compared to the dynamic Smagorinsky model (DSM), leads to significant improvements in the prediction of the first-and second order statistics of turbulent channel flow.These improvements are observed from relatively low to reasonably high Reynolds numbers and with coarse grids.The evaluation of the EAM was continued by implementing and testing of the EAM in the general-purpose finite-volume code OpenFOAM.Several tests of LES of turbulent channel flow have shown thatthe use of the Rhie and Chow (R&C) interpolation in OpenFOAM induces significant numerical dissipation.A new custom-built solver has been utilized in order to minimize the dissipation without generating significant adverse effects. The use of the EAM, together with the new solver, gives a substantially improved prediction of the mean velocity profiles as compared to predictions using the DSM, resulting in roughly 50% reduction in the grid point requirements to achieve a given degree of accuracy. In periodic hill flow, LES with the EAM agreed reasonably well with the reference dataat different bulk Reynolds numbers and reduced the misprediction of the first- and second order statistics observed in LES with DSM.The reduction of the R&C filter dissipation was also shown to be beneficial for the prediction of the mean quantities. An analysis of the skin friction along the lower wall reveals spanwise-elongated, almost axi-symmetric vortical structures generated by the Kelvin-Helmholtz instability. The structures introduced a significant amount of anisotropy.The last part of the study involved the development of a novel hybrid RANS-LES model where explicit algebraic Reynolds stress modelling is applied in both RANS and LES regions.Validations have been conducted on turbulent channel and periodic hill flows at different Reynolds numbers.The explicit algebraic Reynolds stress model for improved-delayed-detached-eddy simulation (EARSM-IDDES) gives reasonable predictions of the mean quantities and Reynolds stresses in both the geometries considered.The use of EARSM-IDDES, compared to the k-omega SST-IDDES model, improves the estimation of the quantities close to the wall.The present work has proven that the use of EAM in wall-resolved LES of wall-bounded flows in simple and complex geometries leads to a substantial reduction of computational requirements both in high-accuracy and general-purpose codes, compared to the use of eddy-viscosity models.In hybrid simulations the EARSM-IDDES shows a clear potential in capturing the physics of wall-bounded flows.
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| 10. |
- Pouransari, Zeinab, 1982-
(författare)
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Numerical studies of turbulent flames in wall-jet flows
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The present thesis deals with the fundamental aspects of turbulent mixing and non-premixed combustion in the wall-jet flow, which has a close resemblance to many industrial applications. Direct numerical simulations (DNS) of turbulent wall-jets with isothermal and exothermic reactions are performed. In the computational domain, fuel and oxidizer enter separately in a nonpremixed manner and the flow is compressible, fully turbulent and subsonic. The triple “turbulence-chemistry-wall” interactions in the wall-jet flow have been addressed first by focusing on turbulent flow effects on the isothermal reaction, and then, by concentrating on heat-release effects on both turbulence and flame characteristics in the exothermic reaction. In the former, the mixing characteristics of the flow, the key statistics for combustion and the near-wall effects in the absence of thermal effects are isolated and studied. In the latter, the main target was to identify the heat-release effects on the different mixing scales of turbulence. Key statistics such as the scalar dissipation rates, time scale ratios, two-point correlations, one and two-dimensional premultiplied spectra are used to illustrate the heat release induced modifications. Finer small mixing scales were observed in the isothermal simulations and larger vortical structures formed after adding significant amounts of heat-release. A deeper insight into the heat release effects on three-dimensional mixing and reaction characteristics of the turbulent wall-jet flow has been gained by digging in different scales of DNS datasets. In particular, attention has been paid to the anisotropy levels and intermittency of the flow by investigating the probability density functions, higher order moments of velocities and reacting scalars and anisotropy invariant maps for different reacting cases. To evaluate and isolate the Damkohler number effects on the reaction zone structure from those of the heat release a comparison between two DNS cases with different Damkohler numbers but a comparable temperature rise is performed. Furthermore, the wall effects on the flame and flow characteristics, for instance, the wall heat transfer; the near-wall combustion effects on the skin-friction, the isothermal wall cooling effects on the average burning rates and the possibility of formation of the premixed mode within the non-premixed flame are addressed. The DNS datasets are also used for a priori analysis, focused on the heat release effects on the subgrid-scale (SGS) statistics. The findings regarding the turbulence small-scale characteristics, gained through the statistical analysis of the flow have many phenomenological parallels with those concerning the SGS statistics. Finally, a DNS of turbulent reacting wall-jet at a substantially higher Reynolds number is performed in order to extend the applicability range for the conclusions of the present study and figuring out the possible differences.
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