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92 Uppsatser om Hydraulic conductance - Sida 4 av 7

Föroreningsspridning via ledningsgravar : en fältstudie på Köpmanholmens industriområde

Sewer trenches usually contain material with a higher hydraulic conductivity then the adjacent soil. Thus they can serve as paths of preferential flow in a polluted area. Wastewater from factories can also leak from wastewater pipes and pollute the soil in the sewer trenches.The purpose of this project was to investigate pollutions in sewer trenches and in sewer pipes in the industrial area of Köpmanholmen, 20 km south of Örnsköldsvik in the north of Sweden. To make an estimation concerning the potential of transport of pollutions in sewer trenches, hydrological calculations were performed.Leakage to any greater extent did not seem to be a problem in the area. This is the case both for the concrete and the wooden pipes that have served as factory wastewater pipes.

Förslag till ombyggnation av klipp- och bockningsmaskin

This thesis work has been performed on request by SWT (Scandinavia WeldTech AB). SWT manufactures, develop and sell ready to assemble building systems for concrete rafter beam applications. The beams in this system consist of a u-beam that is welded to a flange. To be able to fill the beams with concrete there is holes in the beams top end. The holes are made in a ?punching machine?.  These holes are cut out and the remaining steel piece is bent down in the u-beam.

NEDKYLNING HOS VANLIG B?NA, PHASEOLUS VULGARIS

Beans are a global source of plant-based protein, and in some countries, they constitute a primary source of protein intake. With ongoing climate change, including rising temperatures, it is necessary to adapt beans to ensure a reliable food supply. An important mechanism that many plants have, to cope with high temperatures, is cooling through transpiration. During transpiration, stomata open and release water vapor. Water molecules use heat energy from the leaf to convert into gas, thereby cooling the leaf.

Modellering av manövercylindern för Nosstället på JAS39 Gripen

When models are used to describe physical phenomenon during development or modification of a technical system, it is often possible to reduce both the time needed and the overall development cost. With the use of models it is also possible to investigate the potential of the selected solution, without the need for any expensive details and testrigs. In many cases it is also not possible to test all the aspects regarding the functionality that are desired from the system, without using the complete and final product.In this case a model based approach has been used to optimize the different parameters in the new snubbing mechanism for the Nose Landing Gear Retract Actuator on the JAS39 Gripen.During the simulations, upper and lower boundaries were calculated for the length of the spring and the diameter for the restrictor. The governing constraints were given by the requirements for the retraction time during cold conditions and that the amplitude of the alternating loads in the uplock mechanism were brought to an acceptable level.The most promising results from the simulations were then used in a limited number of trials in the hydraulic rig to verify that the configurations comply with the requirements.The final parameters for the snubbing mechanism were chosen to 35±1mm for the spring and 0.4-0.5 mm diameter for the restrictor..

Undersökning av luftkvaliteten vid småskalig biobränsleförbränning i två kommuner med modellsystemet VEDAIR

An Internet application, VEDAIR, for estimation of air quality in regions with small-scale combustion of bio fuel has been developed by Swedish Meteorological and Hydrological Institute with financing from Swedish Energy Agency and Swedish Environmental Protection Agency. The model contains user interface and a coupled model concept where concentrations of atmospheric pollutions are calculated for regional, urban and local contributions. In this report the model is described and a first study of air quality considering PM10 (particles with a diameter less than 10 µm) in two Swedish municipalities, Vänersborg and Gnosjö, is introduced.According to the result, there are areas with poor air quality even in smaller Swedish municipalities, mostly due to high emission from buildings with older wood heating furnace without hydraulic accumulator.In Vänersborg three areas were analysed in VEDAIR for the year 2003: Vargön, Mariedal and the downtown district. In the whole municipality the upper evaluation threshold for PM10, which is defined as 14 µg/m3 for annual average, was exceeded due to background contribution of particles. In all areas, however, the concentrations of PM10 were less than the environmental quality norms.

Bors E23 - Framtagning av eldriven röravklippningsmaskin

Our Bachelor´s Thesis has been performed in co-operation with Bors Automation & Tool AB.Our task was to develop a servomotor powered tube cutting-machine with initial point fromtoday's hydraulic driven tube cutting machine Bors HYD 23. The purpose with the newconstruction was to achieve a more power-efficient tube cutting machine which could lowerthe power consumption, and also meet the market continued growing demand forenvironmental-conscious production.Bors Automation & Tool gave us relatively free hands in order to enable new thinking ideaswithout following their traditional constructional solutions.Our solution resulted in a construction based on a power source existing of a servomotordrivenrollerscrew, witch provides a more rational use of energy compared with the currentmethod.Bors Automation & Tool AB has decided to fabricate a prototype of Bors E 23 during theautumn of 2007, which they are planning to revile at the Tube 2008 exhibition in Düsseldorf,Germany.NOTE:Due to an agreement signed by the authors in the beginning of this project, no appendix is published at this time.If you want to wiew these documents, please contact the authors..

Modellering av ett bränslesystem i Modelica : tillämpat på ett obemannat flygplan

Mathematical models possible to simulate are of great importance in order to make successful projects in the aircraft manufacturing industry. An aircraft fuel system is very complex, containing pipes, tanks, orifices, valves and pumps. The principal of this thesis is using the tool Easy5, which no longer is considered reliable enough in terms of development and support. This thesis tries to evaluate the Modelica language as a possible alternative to Easy5. To make this evaluation, the components concerned in the fuel library in Easy5 are implemented to the Modelica language.

Framtagande av ny höjdmätningsmetod till försvarets antennhiss 861

This bachelor degree project was carried out at Saab AB Service and Repair, Arboga, Sweden. The objective was to design, construct and implement a new stable and reliable method of measuring the continuous vertical displacement (height) of the military search radar PS861 mounted on a hydraulic powered elevator. The end product needs to be durable enough to be fully operational in the harsh environment of an outdoor elevator shaft and yet as accurate and precise as possible since one of its purposes is to calibrate control equipment. Previously used technique has proven not to meet any of the above mentioned properties.A prototype using a high resolution quadrature output rotary encoder has been developed, allowing a completely digital interface. This new method has been evaluated in laboratory environment where tests have been conducted regarding both reliability and validity.

Krafter på rörsystem vid transient flöde : En jämförelse mellan RELAP5 och Fluent

At Forsmarks Kraftgrupp AB (FKA) forces on pipe systems due to transient flow are frequently calculated as a step to verify their structural integrity. In nuclear industries these forces are often calculated with a one dimensional thermal-hydraulic analysis-code called RELAP5. When calculations regarding more complex geometries are needed, the three dimensional code Fluent is often used. This code is highly time consuming and requires large computational power.This projects aim is to compare calculations of pressure, flow and forces carried out by RELAP5 and Fluent for an arbitrary pipe section during transient flow conditions. This has been accomplished by constructing a simple geometry for which a transient flow is simulated in both programs.

Vinster med återvinning, Stena Recycling

This project operate an environmental assessment of total waste was conducted by using a life cycle assessment (LCA), that examines the environmental benefits of recycling production waste from Atlas Copco at Stena recycling. Atlas Copco is a company engaged in the development and production of rig-mounted hydraulic breakers and handheld air breakers and handheld motorized rotisserie. Stena recycling is a recycling company engaged in recycling, processing and refining of metals, paper, electronics waste and hazardous waste.The purpose of this study is to focus on Stena customer Atlas Copco and evaluate environmental benefits between to recycle and not to do it. The result shows that the total energy gain, resulting from the recycling of waste fractions, lands at 6 990 089 MJ, corresponding to drive 3 times around the Equator with a truck (40 t). The result shows that recycling 3040 kg paper provides an energy gain of (38 600 MJ) compared with burning paper (19 500 MJ) is 19 100 MJ, which corresponds to heat a house for 11 weeks.

En flödesutjämnande driftstrategi för Uppsalas fjärrvärmesystem : En ändrad styrning av framtemperaturen

This thesis examines a possible control strategy to minimize flow fluctuations in Uppsala?s district heating system. High variations in flow rate may lead to complications caused by hydraulic constraints in the district heating system. These complications, such as inadequate pressure and temperature levels, increase the risk of heat delivery failures. It is therefore important to avoid such situations both for the producer and for the customers.Typically, the forward temperature is controlled by using a rough correlation with respect to the outdoor temperature.

Analys av tidsåtgång vid montering av aggregat på Haldex Barnes Hydraules

Haldex Barnes Hydraulics (HBH) is a company which produces hydraulic aggregates for use in forklifts, construction equipment, and trucks. The last two years the company has expanded. This has lead to an insufficient production of aggregates. Thus wishes HBH to increase their production without making to large investments.This report includes a now-state analysis of the problems and where they are. From this a further analysis of possible improvements are made.HBH works mainly with assembling and this is made manually.

Hur effektivt och säkert är ivacaftor vid behandling av cystisk fibros (CF)? : Studier av forcerad expiratorisk volym under den första sekunden (FEV1) hos CF-patienter vid behandling med ivacaftor 

Cystisk fibros (CF) är en kronisk, ärftlig sjukdom, som framför allt drabbar lungorna och kan p.g.a. påverkan på dessa leda till för tidig död. I Sverige är ca 650 personer drabbade av cystisk fibros och det föds runt 20 barn med CF i Sverige varje år.CF beror på förekomst av en eller flera mutationer i genen för Cystic Fibrosis Transmembrane Conductance Regulator (CFTR), vilket leder till defekt CFTR och därmed till rubbad jontransport över cellmembranet. Det finns idag inget botemedel mot CF. Fram till nu har behandlingarna av CF riktats mot sjukdomens symtom.

VVA-strategier för avgastemperaturhöjning på en HD-Dieselmotor

Regulations on the exhaust emissions of HD-diesel engines are becoming more and more stringent, and therefore, emission after-treatment systems are commonly used. These systems rely on catalytic conversion of NOx,CO , and HC emissions, and are thus dependant on temperature. At low load of the engine, exhaust temperatures are not sufficient for the after-treatment components. Therefore, means to increase the exhaust temperature while maintaining low emissions and fuel consumption are needed.The focus of this project has been to develop strategies for the lift profiles of exhaust and intake valves in the engine, with the goal to raise exhaust temperature in combination with low emissions and fuel consumption. The strategies have been tested in a single-cylinder research engine equipped with a hydraulic variable valve actuation system.

Geotermisk fjärrvärme i Gunsta

Gunsta is situated about 10 km east of Uppsala. Today there are plans to establish 1000 new households in Gunsta before year 2030. The required energy for heating houses and water would be distributed via a district heating system, which also includes 200 existing residences. The annual required energy, according to this study, would be 16.2 GWh with a maximal peak effect of 6.9 MW. To meet this need, the study suggests a system with heat pumps to upgrade the 31?C water from a 1.8 kilometre deep borehole.

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