Decoupled Design of Auxiliary Systems for Internal Combustion Engines

This thesis investigated if decoupled design of the air intake and exhaust systems for four-stroke internal combustion engines is possible. Using the information found design guidelines were set up for the formula student team ELiTH Racing. The literature study revealed that the systems are not uncoupled, and the inuence of exhaust geometry on air intake behavior needed more thorough investigation. Experiments were designed, using a single cylinder engine with simple intake and exhaust geometries. The tests were attempted, but had to be abandoned due to time constraints. Successful tests would have yielded results in the form of pressure measurements, froma Prandtl-tube, in the air intake, and footage of smoke tests. As a secondary task the potential of computer simulations during the design process was investigated, which yielded a suggestion on how to set up a complete reasonable computational model of the systems. This also resulted in that the design guidelines included how to use computer simulations for the design process. Finally a few ways to expand this work are presented

Decoupled Design of Auxiliary Systems for Internal Combustion Engines

This thesis investigated if decoupled design of the air intake and exhaust systems for four-stroke internal combustion engines is possible. Using the information found design guidelines were set up for the formula student team ELiTH Racing. The literature study revealed that the systems are not uncoupled, and the inuence of exhaust geometry on air intake behavior needed more thorough investigation. Experiments were designed, using a single cylinder engine with simple intake and exhaust geometries. The tests were attempted, but had to be abandoned due to time constraints. Successful tests would have yielded results in the form of pressure measurements, froma Prandtl-tube, in the air intake, and footage of smoke tests. As a secondary task the potential of computer simulations during the design process was investigated, which yielded a suggestion on how to set up a complete reasonable computational model of the systems. This also resulted in that the design guidelines included how to use computer simulations for the design process. Finally a few ways to expand this work are presented

Ultimate limit state analysis of FRP composite sandwich plates – development of a semi-analytical method

The development of Sandwich PULS, a semi-analytical calculation tool for predicting the ultimate limit state (ULS) of FRP composite sandwich plates is presented. This was done by extending DNV GL’s semi-analytical calculation tool Composite PULS, which is used for quick estimation of the ULS for unstiffened composite plates. ULS was evaluated in terms of the first buckling load and the first ply failure (FPF). The Sandwich PULS code was developed by implementing formulations for sandwich plate theory. First-order shear deformation theory (FSDT) was implemented to include the transverse shear deformations that are highly important for sandwich plates with poor shear stiffness of the core. The Sandwich PULS code was evaluated against nonlinear finite element analyses (FEA). It was concluded that Sandwich PULS shows good agreement with FEA-predicted critical buckling loads. For all inspected plates, Sandwich PULS shows improved results compared to Composite PULS. Differences between Sandwich PULS and FEA are caused by the difference in evaluating shear stiffness. It has been shown that neglecting shear stiffness of faces results in good agreement between Sandwich PULS and FEA, while use of conventional shear correction factors proved to be unfavourable for sandwich plates. It was found that Sandwich PULS is limited in terms of slenderness. Sandwich plates with soft core should not have slenderness below 20 to assure an accurate solution

Optimus Pr\ue5m - Semi-submersible wind farm installation vessel for Blekinge Offshore

In Sweden the government is investing lots of resources in order to meet the energy need with clean and renewable alternatives. Since wind is an unlimited source of energy the exploitations of wind farms is of great interest. This report describes a conceptual design of an innovative offshore wind turbine installation vessel for inland sea conditions, with highest possible energy efficiency and environmental friendly performance in every detail. The customer, Blekinge Offshore, main requirement is to receive a concept with an as low installation cost as possible.The final concept Optimus Pr\ue5m includes one installation vessel, which is a semi-submersible barge, and one support vessel that supply the installation vessel with power and propulsion. The power is distributed from the support vessel to the installation vessel through a power cable. The installation vessel will be self-propelled during the installation phase using electrical motors and thrusters.The installation vessel shall be able to handle gravity foundations and fully assembled wind turbines, transported vertically to the installation site. Foundations and windmills will be fully assembled in Karlshamn port before transit to site. During transit the installation and support vessel are connected to each other in all motions except pitch. This almost total fixed connection makes the two vessels acts like one, which gives the joint vessel excellent manoeuvrability. When installing foundations, the installation vessel and the support vessel disconnect. The installation vessel places the foundation at the planned location by ballasting until the foundation has reached the seabed. After de-ballasting the installation vessel and support vessel connects again and transit back to the harbour. When installing wind turbines the two vessels are kept connected and makes highly accurate positioning for the installation possibl

Nusinersen versus Sham Control in Later-Onset Spinal Muscular Atrophy

International audienceBACKGROUND Nusinersen is an antisense oligonucleotide drug that modulates pre-messenger RNA splicing of the survival motor neuron 2 (SMN2) gene. It has been developed for the treatment of spinal muscular atrophy (SMA). METHODS We conducted a multicenter, double-blind, sham-controlled, phase 3 trial of nusinersen in 126 children with SMA who had symptom onset after 6 months of age. The children were randomly assigned, in a 2: 1 ratio, to undergo intrathecal administration of nusinersen at a dose of 12 mg (nusinersen group) or a sham procedure (control group) on days 1, 29, 85, and 274. The primary end point was the least-squares mean change from baseline in the Hammersmith Functional Motor Scale-Expanded (HFMSE) score at 15 months of treatment; HFMSE scores range from 0 to 66, with higher scores indicating better motor function. Secondary end points included the percentage of children with a clinically meaningful increase from baseline in the HFMSE score (>= 3 points), an outcome that indicates improvement in at least two motor skills. RESULTS In the prespecified interim analysis, there was a least-squares mean increase from baseline to month 15 in the HFMSE score in the nusinersen group (by 4.0 points) and a least-squares mean decrease in the control group (by -1.9 points), with a significant between-group difference favoring nusinersen (least-squares mean difference in change, 5.9 points; 95% confidence interval, 3.7 to 8.1; P< 0.001). This result prompted early termination of the trial. Results of the final analysis were consistent with results of the interim analysis. In the final analysis, 57% of the children in the nusinersen group as compared with 26% in the control group had an increase from baseline to month 15 in the HFMSE score of at least 3 points (P< 0.001), and the overall incidence of adverse events was similar in the nusinersen group and the control group (93% and 100%, respectively). CONCLUSIONS Among children with later-onset SMA, those who received nusinersen had significant and clinically meaningful improvement in motor function as compared with those in the control group. (Funded by Biogen and Ionis Pharmaceuticals; CHERISH ClinicalTrials. gov number, NCT02292537.