Electric Vehicle Traction and Rolling Resistance in Winter

1998 ◽  
Vol 26 (2) ◽  
pp. 64-83 ◽  
Author(s):  
S. Shoop
Keyword(s):  
Electric Vehicle ◽  
Rolling Resistance ◽  
Weather Conditions ◽  
Cold Weather ◽  
Tire Pressure ◽  
Air Drag ◽  
Cold Temperatures ◽  
Winter Conditions ◽  
Total Vehicle ◽  
Primary Contribution

Abstract Low rolling resistance tires help optimize the economy of electric vehicle (EV) operation. Five types of EV tires were evaluated under cold weather conditions and compared with traditional winter tires in terms of traction and rolling resistance. Other contributions to vehicle resistance (brake drag, wheel bearing resistance, driveline resistance, and air drag) were also measured and used to estimate changes in total vehicle resistance and associated changes in range with temperature. At low speeds, tire rolling resistance is the primary contribution to increased vehicle resistance at cold temperatures, with snow tires having both higher resistance and a stronger dependence on temperature than low rolling resistance tires. Lowering tire pressure increases both resistance and temperature dependence for most tires but also improves traction and therefore may serve as a temporary safety measure in winter conditions.

“EXTREME” COLD WEATHER OIL SPILL RESPONSE TECHNIQUES & STRATEGIES – ICE & SNOW ENVIRONMENTS

2005 ◽  
Vol 2005 (1) ◽  
pp. 521-525
Author(s):  
Carl J. Oskins ◽  
Dee Bradley
Keyword(s):  
Oil Spill ◽  
Oil Pollution ◽  
Weather Conditions ◽  
Climatic Conditions ◽  
Cold Weather ◽  
Worst Case ◽  
Cold Temperatures ◽  
Physical Constraints ◽  
Adverse Weather ◽  
Extreme Cold

ABSTRACT The logistics of cleaning up spilled oil in cold weather differ from those involved in cleaning up a warm water oil spill. The cleanup is complicated by climatic conditions, the presence of various forms of ice, and the changes that take place in the oil itself in response to cold temperatures. The physical constraints on the cleanup of an extreme cold weather oil spill include the fact that during winter months, it's often too cold to work and daylight becomes a premium. The Oil Pollution Act of 1990 states that when designing a Facility Response Plan, it should be based on a Worst Case Oil Spill in the Most Adverse Weather Conditions. In many parts of the country, Extreme Cold Weather qualifies as the most adverse condition. Almost every aspect of spill response is affected by extreme temperatures. The equipment changes as does the PPE worn by responders. Ice can contain and entrain oil that is spilled and may work both for and against recovery. Utilizing techniques such as ice slotting can aid immensely in recovery operations, but the safety of responders must always remain paramount.

Analysis of Embedded Blade Root Carrot and T-Bolt Connections Subject to Cold Weather Conditions Using a Finite Element Model

2010 ◽  
Author(s):  
Patricio Lillo ◽  
Curran Crawford
Keyword(s):  
Finite Element ◽  
Thermal Stresses ◽  
Weather Conditions ◽  
Element Model ◽  
Cold Weather ◽  
Cold Temperatures ◽  
Operational Conditions ◽  
Blade Root ◽  
Applied Loading ◽  
Composite Blades

Canada has aggressive targets for introducing wind energy across the country, but also faces challenges in achieving these goals due to the harsh Canadian climate. One issue which has received little attention in other countries not experiencing these extremes is the behavior of the composite blades in winter conditions. The scope of this work is to determine and analyze the static stresses on the blade root during operational conditions at extreme cold temperatures. The paper analyses the stresses in the root of the composite blades, specifically two blade-hub connection methods: embedded root carrots and T-bolts. Finite element models of the root are proposed to properly simulate boundary conditions, applied loading and thermal stresses for a 1.5 MW wind turbine. Finally, it is shown that the blade root is strongly affected by the thermal stresses caused by the mismatch and orthotrophy of the coefficients of thermal expansion of the blade root constituents.

Vulnerability of sweet cherry cultivars to continuous periods of spring frosts in Plovdiv, Bulgaria

2020 ◽  
Vol 12 (4) ◽  
pp. 348-352
Author(s):  
S. Malchev ◽  
S. Savchovska
Keyword(s):  
Sweet Cherry ◽  
Weather Conditions ◽  
Frost Damage ◽  
Cold Weather ◽  
Bud Burst ◽  
Intermediate Group ◽  
Air Temperatures ◽  
Wide Range ◽  
Group Form ◽  
Sweet Cherry Cultivars

Abstract. The periods with continuous freezing air temperatures reported during the spring of 2020 (13 incidents) affected a wide range of local and introduced sweet cherry cultivars in the region of Plovdiv. They vary from -0.6°C on March 02 to -4.9°C on March 16-17. The duration of influence of the lowest temperatures is 6 and 12 hours between March 16 and 17. The inspection of fruit buds and flowers was conducted twice (on March 26 and April 08) at different phenological stages after continuous waves of cold weather conditions alternated with high temperatures. During the phenological phase ‘bud burst’ (tight cluster or BBCH 55) some of the flowers in the buds did not develop further making the damage hardly detectable. The most damaged are hybrid El.28-21 (95.00%), ‘Van’ (91.89%) and ‘Bing’ (89.41%) and from the next group ‘Lapins’ (85.98%) and ‘Rosita’ (83.33%). A larger intermediate group form ‘Kossara’ (81.67%), ‘Rozalina’ (76.00%), ‘Sunburst’ (75.00%), ‘Bigarreau Burlat’ (69.11%) and ‘Kuklenska belitza’ (66.67%). Candidate-cultivar El.17-90 ‘Asparuh’ has the lowest frost damage values of 55.00% and El.17-37 ‘Tzvetina’ with damage of 50.60%.

Heating up trickling filters to tackle cold weather conditions

2000 ◽  
Vol 41 (1) ◽  
pp. 163-166 ◽  
Author(s):  
W. Gebert ◽  
P.A. Wilderer
Keyword(s):  
Waste Heat ◽  
Treatment Plant ◽  
Weather Conditions ◽  
Pilot Scale ◽  
Cold Weather ◽  
Filling Material ◽  
Trickling Filter ◽  
Biofilm Thickness ◽  
Trickling Filters ◽  
Biofilm Support

The investigated effects of heating the filling material in trickling filters were carried out at the Ingolstadt wastewater treatment plant, Germany. Two pilot scale trickling filters were set up. Heat exchanger pipings were embedded in the filter media of one of these trickling filters, and the temperature in the trickling filter was raised. The other trickling filter was operated under normal temperature conditions, and was used as a control. The results clearly demonstrate that the performance of trickling filters cannot be constantly improved by heating the biofilm support media. A sustained increase of the metabolic rates did not occur. The decrease of the solubility of oxgen in water and mass transfer limitations caused by an increase of the biofilm thickness are the main reasons for that. Thus, the heating of trickling filters (e.g. by waste heat utilization) in order to increase the capacity of trickling filters under cold weather conditions cannot be recommended.

scholarly journals Cold weather is a predisposing factor for testicular torsion in a tropical country. A retrospective study

2014 ◽  
Vol 133 (3) ◽  
pp. 187-190 ◽  
Author(s):  
Daniel de Oliveira Gomes ◽  
Rafael Rocha Vidal ◽  
Bruno Figueiredo Foeppel ◽  
Danilo Fiorindo Faria ◽  
Minori Saito
Keyword(s):  
Retrospective Study ◽  
Symptom Onset ◽  
Testicular Torsion ◽  
Weather Conditions ◽  
Cold Weather ◽  
Predisposing Factor ◽  
Tropical Country ◽  
Etiologic Role ◽  
Urological Emergency

CONTEXT AND OBJECTIVE:Testicular torsion is a medical and urological emergency because it can lead to loss of the organ. The theory of seasonal testicular torsion occurrence is based on studies from institutions located in cold and temperate regions. The objective here was to determine whether cold weather is associated with higher incidence of testicular torsion in a tropical country, such as Brazil.DESIGN AND SETTING:Retrospective study, conducted in a tertiary and teaching hospital.METHODS:Patients with acute testicular torsion confirmed by surgery between April 2006 and March 2011 were studied. Information on weather conditions at the time of symptom onset was collected.RESULTS:A total of 64 testicular torsion cases were identified. The months with the highest incidences of testicular torsion were June (16%), July (19%) and August (11%), which had the lowest mean temperatures, of 17.6 °C, 16.4 °C and 18.2 °C, respectively. Eleven percent of cases occurred during spring (October to December), 16% occurred in summer (January to March), 34% occurred in fall (April to June) and 39% occurred in winter (July to September). There was a significant association between the incidence of testicular torsion and the season (fall and winter), P < 0.001.CONCLUSIONS:Testicular torsion follows a seasonal association even in a tropical country, and is more frequent in the colder months of the year, namely fall and winter, when almost three-quarters of the cases occurred. These observations add further evidence that cold weather has an etiologic role in testicular torsion occurrence.

The Study of Fuel-Saving Technology of GSI

2014 ◽  
Vol 1070-1072 ◽  
pp. 392-397
Author(s):  
Jun Hui Xu ◽  
Ming Qiu Gao ◽  
Ji Qiang Gao ◽  
Xiang Bao
Keyword(s):  
Fuel Consumption ◽  
Fuel Economy ◽  
Rolling Resistance ◽  
Fuel Saving ◽  
Pressure Monitoring ◽  
Tire Pressure ◽  
Engine Efficiency ◽  
Tire Pressure Monitoring System ◽  
The Eu

In the background of the main technologies of fuel economy in automobiles developed to a certain stage, it is necessary to reduce fuel consumption and increase the engine efficiency by developing other auxiliary technologies such as improving the ratio of pure energy drive, low rolling resistance tires, tire pressure monitoring system and gear shift indicators (GSI). This article introduces the principle of GSI, analyses how GSI works in improving engine efficiency, and then evaluates the method for determination of the relative saving rate of fuel consumption, which method was introduced in the EU regulation EC No. 65/2012.

scholarly journals Ice fog monitoring near Fairbanks, AK

2021 ◽  
Author(s):  
Dragos Vas ◽  
Steven Peckham ◽  
Carl Schmitt ◽  
Martin Stuefer ◽  
Ross Burgener ◽  
...  
Keyword(s):  
Power Generation ◽  
Environmental Conditions ◽  
Weather Conditions ◽  
Cold Weather ◽  
The Arctic ◽  
Local Power ◽  
Environmental Complexity ◽  
Ice Fog ◽  
Innovative Methods ◽  
Generation Facility

Ice fog events, which occur during the Arctic winter, result in greatly decreased visibility and can lead to an increase of ice on roadways, aircraft, and airfields. The Fairbanks area is known for ice fog conditions, and previous studies have shown these events to be associated with moisture released from local power generation. Despite the identified originating mechanism of ice fog, there remains a need to quantify the environmental conditions controlling its origination, intensity, and spatial extent. This investigation focused on developing innovative methods of identifying and characterizing the environmental conditions that lead to ice fog formation near Fort Wainwright, Alaska. Preliminary data collected from December 2019 to March 2020 suggest that ice fog events occurred with temperatures below −34°C, up to 74% of the time ice fog emanated from the power generation facility, and at least 95% of ice particles during ice fog events were solid droxtals with diameters ranging from 7 to 50 μm. This report documents the need for frequent and detailed observations of the meteorological conditions in combination with photographic and ice particle observations. Datasets from these observations capture the environmental complexity and the impacts from energy generation in extremely cold weather conditions.

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