scholarly journals Experimental and Numerical Testing of Ambient Temperature Impact on Lifespans of Cuffs of Vehicles’ Steering Systems

2020 ◽  
Vol 10 (12) ◽  
pp. 4371
Author(s):  
Radoje Vujadinović ◽  
Vladimir Pajković ◽  
Sreten Simović ◽  
Milanko Damjanović ◽  
Petar Nikčević
Keyword(s):  
Numerical Analysis ◽  
Ambient Temperature ◽  
Steering System ◽  
Ansys Software ◽  
Software Environment ◽  
Numerical Testing ◽  
Northern Areas ◽  
Protective Element ◽  
Temperature Impact ◽  
The Impact

The steering system represents one of the most important systems of active safety in vehicles. The process of a steering system failure usually starts with the failure of its protective element (cuff). Numerous factors influence a cuff’s lifespan, but the research subject of this paper is the impact of ambient temperature. The goal of this research is the experimental verification of the finding that vehicles used in northern areas require more frequent interventions in their steering systems than vehicles used in the south. A simulator performing a motion similar to the work of a cuff during a vehicle’s motion was made for the purpose of the research. A refrigerating chamber where cuffs were tested at temperatures from −4 °C to −20 °C was also made. A numerical analysis, with the ANSYS software environment, was also carried out. The numerical analysis shows that the failure of a cuff could be expected at almost the same point at which it was experimentally proven. Therefore, the failure, namely the breaking of a cuff, is not only a consequence of the material’s fatigue due to a big number of oscillations, but it also depends upon the impact of ambient temperature where the vehicle is used.

scholarly journals Analysis of the Driving Altitude and Ambient Temperature Impact on the Conversion Efficiency of Oxidation Catalysts

2021 ◽  
Vol 11 (3) ◽  
pp. 1283
Author(s):  
José Ramón Serrano ◽  
Pedro Piqueras ◽  
Enrique José Sanchis ◽  
Bárbara Diesel
Keyword(s):  
Ambient Temperature ◽  
Conversion Efficiency ◽  
Mass Flow ◽  
Engine Performance ◽  
Oxidation Catalyst ◽  
Ambient Conditions ◽  
Engine Operation ◽  
Temperature Impact ◽  
Conversion Efficiencies ◽  
The Impact

Worldwide emission standards are extending their requirements to cover engine operation under extreme ambient conditions and fill the gap between the type-approval and real driving conditions. The new ambient boundaries affect the engine performance and raw emissions as well as the efficiency of the exhaust aftertreatment systems. This study evaluates the impact of high altitude and low ambient temperature on the light-off temperature and conversion efficiency of an oxidation catalyst. The results are compared in a common range of exhaust mass flow and temperature with the baseline sea-level operation at 20 °C. A reduction of CO and HC conversion efficiencies was found at 2500 m and −7 °C, with a relevant increase of the light-off temperature for both of the pollutants. The analysis of the experimental data was complemented with the use of a catalyst model to identify the causes leading to the deterioration of the CO and HC light-off. The use of the model allowed for identifying, for the same exhaust mass flow and temperature, the contributions to the variation of conversion efficiency caused by the change in engine-out emissions and tailpipe pressure, which are, in turn, manifested in the variation of the reactants partial pressure and dwell time as governing parameters.

TEM comparison of osmium vs osmium with potassium ferricyanide secondary fixatives and the impact of secondary fixative temperature on tissue preservation/contrast quality

1996 ◽  
Vol 54 ◽  
pp. 910-911
Author(s):  
J. W. Horn ◽  
B. J. Dovey-Hartman ◽  
V. P. Meador
Keyword(s):  
Osmium Tetroxide ◽  
Potassium Ferricyanide ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Microscopic Evaluation ◽  
Cacodylate Buffer ◽  
Transmission Electron Microscopic ◽  
Glutaraldehyde Solution ◽  
Temperature Impact ◽  
The Impact

Osmium tetroxide (OsO4) is a universally used secondary fixative for routine transmission electron microscopic evaluation of biological specimens. Use of OsO4 results in good ultrastructural preservation and electron density but several factors, such as concentration, length of exposure, and temperature, impact overall results. Potassium ferricyanide, an additive used primarily in combination with OsO4, has mainly been used to enhance the contrast of lipids, glycogen, cell membranes, and membranous organelles. The purpose of this project was to compare the secondary fixative solutions, OsO4 vs. OsO4 with potassium ferricyanide, and secondary fixative temperature for determining which combination gives optimal ultrastructural fixation and enhanced organelle staining/contrast.Fresh rat liver samples were diced to ∼1 mm3 blocks, placed into porous processing capsules/baskets, preserved in buffered 2% formaldehyde/2.5% glutaraldehyde solution, and rinsed with 0.12 M cacodylate buffer (pH 7.2). Tissue processing capsules were separated (3 capsules/secondary fixative.solution) and secondarily fixed (table) for 90 minutes. Tissues were buffer rinsed, dehydrated with ascending concentrations of ethanol solutions, infiltrated, and embedded in epoxy resin.

The Impact of Light Polarisation on Light Field of Scenes with Multiple Reflections

2020 ◽  
pp. 108-115 ◽  
Author(s):  
Vladimir P. Budak ◽  
Anton V. Grimaylo
Keyword(s):  
Mathematical Model ◽  
Light Field ◽  
Global Illumination ◽  
Multiple Reflections ◽  
Software Environment ◽  
The Monte Carlo Method ◽  
Mueller Matrices ◽  
Volume Integration ◽  
The Impact

The article describes the role of polarisation in calculation of multiple reflections. A mathematical model of multiple reflections based on the Stokes vector for beam description and Mueller matrices for description of surface properties is presented. On the basis of this model, the global illumination equation is generalised for the polarisation case and is resolved into volume integration. This allows us to obtain an expression for the Monte Carlo method local estimates and to use them for evaluation of light distribution in the scene with consideration of polarisation. The obtained mathematical model was implemented in the software environment using the example of a scene with its surfaces having both diffuse and regular components of reflection. The results presented in the article show that the calculation difference may reach 30 % when polarisation is taken into consideration as compared to standard modelling.

Evaluation the effect of the ambient temperature on the liquid petroleum gas transportation pipeline

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ammar Ali Abd ◽  
Samah Zaki Naji ◽  
Ching Thian Tye ◽  
Mohd Roslee Othman
Keyword(s):  
Energy Consumption ◽  
Greenhouse Gases ◽  
Ambient Temperature ◽  
Phase Change ◽  
Liquid State ◽  
Pump Energy ◽  
Compressible Liquid ◽  
Liquefied Petroleum Gas ◽  
Efficient Design ◽  
The Impact

Abstract Liquefied petroleum gas (LPG) plays a major role in worldwide energy consumption as a clean source of energy with low greenhouse gases emission. LPG transportation is exhibited through networks of pipelines, maritime, and tracks. LPG transmission using pipeline is environmentally friendly owing to the low greenhouse gases emission and low energy requirements. This work is a comprehensive evaluation of transportation petroleum gas in liquid state and compressible liquid state concerning LPG density, temperature and pressure, flow velocity, and pump energy consumption under the impact of different ambient temperatures. Inevitably, the pipeline surface exchanges heat between LPG and surrounding soil owing to the temperature difference and change in elevation. To prevent phase change, it is important to pay attention for several parameters such as ambient temperature, thermal conductivity of pipeline materials, soil type, and change in elevation for safe, reliable, and economic transportation. Transporting LPG at high pressure requests smaller pipeline size and consumes less energy for pumps due to its higher density. Also, LPG transportation under moderate or low pressure is more likely exposed to phase change, thus more thermal insulation and pressure boosting stations required to maintain the phase envelope. The models developed in this work aim to advance the existing knowledge and serve as a guide for efficient design by underling the importance of the mentioned parameters.

scholarly journals A novel mouse model of heatstroke accounting for ambient temperature and relative humidity

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Kazuyuki Miyamoto ◽  
Keisuke Suzuki ◽  
Hirokazu Ohtaki ◽  
Motoyasu Nakamura ◽  
Hiroki Yamaga ◽  
...  
Keyword(s):  
Gene Expression ◽  
Body Temperature ◽  
Relative Humidity ◽  
Ambient Temperature ◽  
Core Body Temperature ◽  
Heat Exposure ◽  
Organ Damage ◽  
Core Body ◽  
The Impact ◽  
Treatment Water

Abstract Background Heatstroke is associated with exposure to high ambient temperature (AT) and relative humidity (RH), and an increased risk of organ damage or death. Previously proposed animal models of heatstroke disregard the impact of RH. Therefore, we aimed to establish and validate an animal model of heatstroke considering RH. To validate our model, we also examined the effect of hydration and investigated gene expression of cotransporter proteins in the intestinal membranes after heat exposure. Methods Mildly dehydrated adult male C57/BL6J mice were subjected to three AT conditions (37 °C, 41 °C, or 43 °C) at RH > 99% and monitored with WetBulb globe temperature (WBGT) for 1 h. The survival rate, body weight, core body temperature, blood parameters, and histologically confirmed tissue damage were evaluated to establish a mouse heatstroke model. Then, the mice received no treatment, water, or oral rehydration solution (ORS) before and after heat exposure; subsequent organ damage was compared using our model. Thereafter, we investigated cotransporter protein gene expressions in the intestinal membranes of mice that received no treatment, water, or ORS. Results The survival rates of mice exposed to ATs of 37 °C, 41 °C, and 43 °C were 100%, 83.3%, and 0%, respectively. From this result, we excluded AT43. Mice in the AT 41 °C group appeared to be more dehydrated than those in the AT 37 °C group. WBGT in the AT 41 °C group was > 44 °C; core body temperature in this group reached 41.3 ± 0.08 °C during heat exposure and decreased to 34.0 ± 0.18 °C, returning to baseline after 8 h which showed a biphasic thermal dysregulation response. The AT 41 °C group presented with greater hepatic, renal, and musculoskeletal damage than did the other groups. The impact of ORS on recovery was greater than that of water or no treatment. The administration of ORS with heat exposure increased cotransporter gene expression in the intestines and reduced heatstroke-related damage. Conclusions We developed a novel mouse heatstroke model that considered AT and RH. We found that ORS administration improved inadequate circulation and reduced tissue injury by increasing cotransporter gene expression in the intestines.

Upgraded Railway Front Searchlight Design Plastic Deformations by its Vibrations with Resonance Frequencies

2016 ◽  
Vol 684 ◽  
pp. 111-119 ◽  
Author(s):  
Stanislav Rafaelevich Abulkhanov ◽  
Dmitrii Sergeevich Goryainov
Keyword(s):  
Natural Frequencies ◽  
Ansys Software ◽  
Software Environment ◽  
Low Frequencies ◽  
Plastic Deformations ◽  
Vibration Resistance ◽  
First Case ◽  
Resonance Frequencies ◽  
The One ◽  
Electric Lamp

Natural frequencies of the four upgraded front searchlight designs were received in ANSYS software environment. In the first case serial front searchlight incandescent electric lamp was replaced by a LED group which was mounted on the one-piece cylinder backing. The second front searchlight design had the backing which was upgraded by a radial ribs and concentric rigidity ferrules. Analyze of the backing deformation character by vibrations with the natural frequencies established a number of design solutions which make it possible to raise front searchlight vibration resistance. By the front searchlight model were established that the natural frequencies of the searchlight with the one-piece backing appertain to the whole range of the train vibrations. Natural frequencies of the backing with perforation, rigidity ferrules, and radial ribs appertain to the low frequencies of the railway locomotive vibrations spectrum. On basis of devised methodology of analyze of the deformation and natural frequencies of the surface carrying a LED group the vibration-proof searchlight design was introduced and researched.

Silane Functionalized Ethylene/Diene Copolymer Modifiers in Composites of Heterophasic Polypropylene and Microsilica

2007 ◽  
Vol 15 (5) ◽  
pp. 343-355 ◽  
Author(s):  
S. Lipponen ◽  
P. Pietikäinen ◽  
U. Vainio ◽  
R. Serimaa ◽  
J.V. Seppälä
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Impact Strength ◽  
Ambient Temperature ◽  
Metallocene Catalyst ◽  
The Poor ◽  
Rubber Toughened ◽  
Rubbery Phase ◽  
The Impact

Ethylene/1,7-octadiene copolymer was polymerised with metallocene catalyst and hydrosilylated to form silane functionalised polyethylenes (PE-co-SiX, X=Cl, OEt, Ph). The functionalised species were tested as modifiers in composites of rubber toughened polypropylene (heterophasic PP, hPP) and microsilica filler (μSi). A metallocene-based functionalised PE (PE-co-SiF) produced earlier in our laboratory and three commercial grades of functionalised polyolefins (one PE- and two PP-based) were used as reference modifiers. Major differences were seen in the toughness of the composites both above and below the glass transition temperature (Tg) of PP. In addition to increasing the stiffness, the microsilica filler enhanced the toughness of the heterophasic polypropylene by over 200% at ambient temperature. Below the Tg of PP (at −20 °C), the influence of μSi was the opposite and the impact strength of the hPP/μSi composite was below that of unfilled hPP. With the addition of just 2 wt% of functionalised polyethylene, the poor cold toughness of hPP/μSi composite was improved by nearly 100%. With the same addition, the toughness of the composites at ambient temperature was improved by 50 to 100% compared with the unfilled hPP. This behaviour was explained by significant changes in the fracture mechanism. Addition of functionalised PE increased the concentration of microsilica in the rubbery phase, allowing the crack to enter that phase. The rubbery phase was also able to absorb a large amount of impact energy below the glass transition temperature of PP.

Energy or carbon? Exploring the relative size of universal zero carbon and zero energy design spaces

2018 ◽  
Vol 40 (3) ◽  
pp. 319-339 ◽  
Author(s):  
Anna Parkin ◽  
Manuel Herrera ◽  
David A Coley
Keyword(s):  
Design Space ◽  
Relative Size ◽  
Building Design ◽  
Zero Energy ◽  
Software Environment ◽  
Space Forms ◽  
Regulatory Frameworks ◽  
Regulatory Standards ◽  
Zero Carbon ◽  
The Impact

One aim of zero carbon, or zero energy, buildings is to help slow climate change. However, regulatory definitions frequently miss substantial emissions, for example ones associated with the materials the building is constructed from, thereby compromising this goal. Unfortunately, including such emissions might restrict the design space, reduce architectural freedom or greatly increase costs. This work presents a new framework for examining the problem. The zero carbon/energy design and regulatory space forms a sub-space of the hyper-volume enclosing all possible designs and regulatory frameworks. A new mathematical/software environment was developed which allows the size and shape of this sub-space to be investigated for the first time. Twenty-four million building design/regulatory standard combinations were modelled and assessed using a tree classification approach. It was found that a worldwide zero standard that includes embodied emissions is possible and is easier to achieve if a carbon rather than an energy metric is adopted, with the design space twice the size for a carbon metric. This result is important for the development of more encompassing regulations, and the novel methods developed applicable to other aspects of construction controlled by regulation where there is the desire to examine the impact of new regulations prior to legislation. Practical application: As energy standards become more strict, and given the growth in non-regulatory standards (such as Passivhaus), there is the need to study the potential impact of any element of a standard on the range of designs that can be built or the materials that can be used. This work sets out a general framework and method for doing this. The approach and results will be of interest to policy makers, but also to engineers and architects wondering what the key constraints to design the adoption of various philosophies to low energy/carbon standards might have within their work. For example, the implications of the building standard (or client) requiring embodied emissions to be included or the energy balance period for renewable generation to be monthly, not annual.

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