WorldWideScience

Sample records for aquaplanes

  1. Predicting aquaplaning performance from tyre profile images with machine learning

    OpenAIRE

    Weyde, T.; Slabaugh, G.G.; Fontaine, G.; Bederna, C.

    2013-01-01

    The tread of a tyre consists of a profile (pattern of grooves, sipes, and blocks) mainly designed to improve wet performance and inhibit aquaplaning by providing a conduit for water to be expelled underneath the tyre as it makes contact with the road surface. Testing different tread profile designs is time consuming, as it requires fabrication and physical measurement of tyres. We propose a supervised machine learning method to predict tyres’ aquaplaning performance based on the tread profile...

  2. Leaf roll-up and aquaplaning in strong winds and floods

    CERN Document Server

    Miller, Laura; Santhanakrishnan, Arvind

    2008-01-01

    Flexible plants, fungi, and sessile animals are thought to reconfigure in the wind and water to reduce the drag forces that act upon them. In strong winds, for example, leaves roll up into cone shapes that reduce flutter and drag when compared to paper cut-outs with similar shapes and flexibility. During flash floods, herbaceous broad leaves aquaplane on the surface of the water which reduces drag. Simple mathematical models of a flexible beam immersed in a two-dimensional flow will also reconfigure in flow. What is less understood is how the mechanical properties of a two-dimensional leaf in a three-dimensional flow will passively allow roll up and aquaplaning. In this study, we film leaf roll-up and aquaplaning in tree and vine leaves in both strong winds and water flows.

  3. Aquaplaning : ongevallen op nat wegdek.

    NARCIS (Netherlands)

    Welleman, A.G.

    1980-01-01

    If the road surface is wet a vehicle does not always immediately react to the driver's actions such as braking and steering, because there is a film of water between tyre and road surface. If this water cannot be expelled fast enough, the direct contact between tyre and surface is lost with the cons

  4. Aquaplaning, een aspect van de verkeersveiligheid.

    NARCIS (Netherlands)

    Welleman, A.G. & Schlösser, L.H.M.

    1980-01-01

    If the road surface is wet a vehicle does not always react immediately to the driver's action as braking and steering because between tyre and surface there is a film of water. If this water cannot be expelled fast enough, the direct contact between tyre and surface is lost with the consequence that

  5. Three 3-axis accelerometers fixed inside the tyre for studying contact patch deformations in wet conditions

    Science.gov (United States)

    Niskanen, Arto J.; Tuononen, Ari J.

    2014-05-01

    The tyre-road contact area was studied visually by means of a high-speed camera and three accelerometers fixed to the inner liner of the tyre carcass. Both methods show a distorted contact area in wet conditions, but interesting differences appeared. First, the contact area in full aquaplaning seems strongly distorted on a glass plate when subjected to visual inspection, while the accelerometers indicate a more even hydrodynamic aquaplaning contact length (CL) across the tyre width. Secondly, the acceleration sensors predict the clear shortening of the CL of the tyre before the critical aquaplaning speed. It can be concluded that the visual contact area and shape are heavily dependent on the transparency of the liquid and smoothness of the glass. Meanwhile, the tyre sensors can provide a CL estimate on any road surface imaginable.

  6. Time resolved analysis of water drainage in porous asphalt concrete using neutron radiography.

    Science.gov (United States)

    Poulikakos, L D; Sedighi Gilani, M; Derome, D; Jerjen, I; Vontobel, P

    2013-07-01

    Porous asphalt as a road surface layer controls aquaplaning as rain water can drain through its highly porous structure. The process of water drainage through this permeable layer is studied using neutron radiography. Time-resolved water configuration and distribution within the porous structure are reported. It is shown that radiography depicts the process of liquid water transport within the complex geometry of porous asphalt, capturing water films, filled dead end pores and water islands.

  7. Clean-up plan for the Rioja region of Alava (Northern Spain); Plan de saneamiento de la Rioja Alavesa

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Orue, J.M. [Servicio de Aguas Diputacion Foral de Alava, Vitoria (Spain); Nieves de la Vega Sedo, G.

    1996-08-01

    Requirements of wastewater discharges, in order to maintain and improve receiving water qualities, create a demand of means of wastewater management besides implementation of control systems, technical and economical management programs and financing. In this background, Direccion de Medio Ambiente of Diputacion Foral de Alava, through its Water Service, has settled the need of a integral planning for wastewater management in Rioja Alavesa. This job has been commanded to the engineering consulting AQUA/PLAN, S.A. (Author)

  8. Time resolved analysis of water drainage in porous asphalt concrete using neutron radiography.

    Science.gov (United States)

    Poulikakos, L D; Sedighi Gilani, M; Derome, D; Jerjen, I; Vontobel, P

    2013-07-01

    Porous asphalt as a road surface layer controls aquaplaning as rain water can drain through its highly porous structure. The process of water drainage through this permeable layer is studied using neutron radiography. Time-resolved water configuration and distribution within the porous structure are reported. It is shown that radiography depicts the process of liquid water transport within the complex geometry of porous asphalt, capturing water films, filled dead end pores and water islands. PMID:23500651

  9. With a flick of the lid: a novel trapping mechanism in Nepenthes gracilis pitcher plants.

    Directory of Open Access Journals (Sweden)

    Ulrike Bauer

    Full Text Available Carnivorous pitcher plants capture prey with modified leaves (pitchers, using diverse mechanisms such as 'insect aquaplaning' on the wet pitcher rim, slippery wax crystals on the inner pitcher wall, and viscoelastic retentive fluids. Here we describe a new trapping mechanism for Nepenthes gracilis which has evolved a unique, semi-slippery wax crystal surface on the underside of the pitcher lid and utilises the impact of rain drops to 'flick' insects into the trap. Depending on the experimental conditions (simulated 'rain', wet after 'rain', or dry, insects were captured mainly by the lid, the peristome, or the inner pitcher wall, respectively. The application of an anti-slip coating to the lower lid surface reduced prey capture in the field. Compared to sympatric N. rafflesiana, N. gracilis pitchers secreted more nectar under the lid and less on the peristome, thereby directing prey mainly towards the lid. The direct contribution to prey capture represents a novel function of the pitcher lid.

  10. Aspects of Applying Weather Radar Based Nowcast for Highways in Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Quist, MIchael; Thorndahl, Søren Liedtke

    nowcast can be used for two scenarios: 1) Safety - reduced visibility and possibility for aquaplaning can jeopardise the safety of the road users 2) Construction and maintenance - ensuring protection against flooding and pollution. The two different applications can represent two different precipitation......The Danish road network consists of 73.331 km. of roads. 3.790 km. of these roads are state roads and are considered as major lines of transportation. Although these roads only represent 5% of the total network, 45% of all traffic is moving along these roads. Application of weather radar based...... on the visibility, rain intensity and rain volume. This can actively be used to optimise basin volumes and to direct critical information to traffic. A system for nowcast dedicated to road applications are under development in Denmark. This paper investigates the different approaches in nowcasting of precipitation...

  11. Tyre contact length on dry and wet road surfaces measured by three-axial accelerometer

    Science.gov (United States)

    Matilainen, Mika; Tuononen, Ari

    2015-02-01

    We determined the tyre contact length on dry and wet roads by measuring the accelerations of the inner liner with a three-axial accelerometer. The influence of the tyre pressure, driving velocity, and tread depth on the contact length was studied in both types of road surface conditions. On dry asphalt the contact length was almost constant, regardless of the driving velocity. On wet asphalt the presence of water could be detected even at low driving velocities (e.g. 20 km/h for a worn tyre) as the contact length began to decrease from that found in the dry asphalt situation. In addition to improving the performance of active safety systems and driver warning systems, the contact length information could be beneficial for classifying and studying the aquaplaning behaviour of tyres.

  12. Time resolved analysis of water drainage in porous asphalt concrete using neutron radiography

    International Nuclear Information System (INIS)

    Porous asphalt as a road surface layer controls aquaplaning as rain water can drain through its highly porous structure. The process of water drainage through this permeable layer is studied using neutron radiography. Time-resolved water configuration and distribution within the porous structure are reported. It is shown that radiography depicts the process of liquid water transport within the complex geometry of porous asphalt, capturing water films, filled dead end pores and water islands. - Highlights: ► The water drainage process in porous asphalt was studied using neutron radiography. ► Despite similar mix designs, different processes of water transport were established. ► Water transport within porous asphalt showed filled dead end pores and water islands