Efficiency of wind fences is evaluated by the reduction of wind velocity and the effective shelter area behind the fence. Fence porosity is the most influential structural parameters in the porous fence design, and has significant impact on the structure of wind velocity and turbulence leeward. In this work, three fences with porosity of 23%, 35% and 45% have been tested under 10m/s inlet velocity ...

This report simulates Purmo type C22 and C33 radiators with both standard calculation and heat transfer method with help of Matlab/Simulink. Simulation results are presented to describe the radiators’ thermal performances with different simulation strategies. The deviations between two different calculation methods are identified and the heat transfer radiator model can be improved with more ...

This paper presents a numerical prediction on the assessment of natural ventilation on a livestock house built in porous panels, aided by Computational Fluid Dynamics techniques. A typical climatic environment in Cold Regions was taken into consideration. The ventilation performances have been assessed by the distribution of indoor air velocity, turbulence intensity and local mean age of air through ...

Crystallographic aspects of heterogeneous plastic flow during ductile tearing are assessed experimentally by combining in situ synchrotron laminography imaging of notched flat samples with a full-field measurement technique and numerical simulations with the crystal plasticity finite element method (CP-FEM). Advantage is taken of the plane strain condition in the region ahead of the notch root (i.e., ...

In this paper, a sensitivity analysis of a continuous stirred tank bioreactor (CSTBR) was conducted to determine a parametrically sensitive regime. The growth of a lactic acid bacterium, namely, <i>Lactobacillus casei</i>, in a pH-controlled CSTBR was considered as a process model. Normalized objective sensitivities of the minimum pH were determined with respect to input parameters. A generalized ...

The rapid oxidation of carbon black (CB) is a major drawback for its use as a catalyst support in polymer electrolyte fuel cells. Here, we synthesize poly[2,20 -(4,40 -bipyridine)-5,50 -bibenzimidazole] (BiPyPBI) as a conducting polymer and use it to functionalize the surface of CB and homogenously anchor platinum metal nanoparticles (Pt-NPs) on a CB surface. The as-prepared materials were ...

Verden står ovenfor store klimaendringer og klimagassmengden fortsetter å øke. For å begrense økning av gjennomsnittstemperaturen må tiltak iverksettes for å redusere utslippene. Betong er det mest anvendte byggematerialet i verden og det brukes dobbelt så mye betong enn andre byggematerialer til sammen. Sementproduksjon antas å bidra til 7-8 prosent av klimagassutslipp på verdensbasis. Betong ...

I den norske byggebransjen i dag er det lite samsvar mellom tilbud og etterspørsel av boliger, og det er dermed behov for økt effektivisering av byggebransjen. Prefabrikasjon som byggemetode har potensiale til å bidra til å øke effektiviteten i bygg- og anleggsnæringen, sett opp mot tradisjonell plassbygd metode. Denne artikkelen har dermed gjennomført en sammenligning av de positive og negative ...

In this paper, the inhibitory effects of added hydrogen in reactor headspace on fermentative hydrogen production from acidogenesis of glucose by a bacterium, Clostridium acetobutylicum, was investigated experimentally in a batch reactor. It was observed that hydrogen itself became an acute inhibitor of hydrogen production if it accumulated excessively in the reactor headspace. A mathematical model ...

Denne oppgaven er en studie om radon i eksisterende bygninger med en casestudie. I forkant av utarbeidelse og utførelse av en tiltakspakke, ble det gjort en litteraturstudie innenfor temaet om radon, situasjonen i Norge og anbefalte tiltak for å redusere radonnivåene i eksisterende boliger. Casestudien omhandler en enebolig i Beisfjord, Narvik kommune. Det har blitt utført bytte av innvendig radonbrønn ...