The effect of pressure on the melting temperature is also accounted for. The model takes into account frictional melting, heat conduction into the ice and the lateral squeeze flow of the lubricating liquid. Friction results from a ploughing force, arising from ice deformation, crushing and extrusion, and from the shear stress in the lubricating Couette flow. The effect of any contact between asperities on both surfaces is neglected. The model describes ice friction in the fully-lubricated, hydrodynamic regime, where a layer of meltwater completely separates the ice and slider surfaces. The model of ice friction described here is for a steel bobsleigh runner sliding on ice at high velocity. This paper addresses only one aspect of ice friction in winter sports, but it is potentially relevant to other applications, particularly surface transportation over ice. Ice friction also affects surface transportation over snow and ice. It also influences the structural forces resulting from ice interactions with fixed and moored structures and with floating vessels. In cold regions, ice friction influences ice interaction with itself, which determines the motion of ice floes. Ice friction affects us in many ways, from slippery roads to winter sports. The mean coefficient ofįriction was found to be mu = (5.3 +/- 2.0) x 10-3 and the mean drag Olympic Oval and at Canada Olympic Park: at the Ice House and on theīobsleigh track during a World Cup competition. Were determined from radar speed measurements taken at the Calgary The coefficient of frictionīetween runners and ice and the drag performance of 2-men bobsleighs The lowest coefficient of friction and that the rocker affects friction The model for flat ice suggests that the flattest runners produce 20☌, in agreement with observations on the Calgary bobsleigh That maximum velocities are obtained for temperatures between -10 and model was adaptedįrom a speed skate model to calculate the coefficient of frictionīetween a bobsleigh runner and a flat ice surface. Surface, from a height of (0.3-1.2) m, and measuring the diameter of The ice hardness was determined byĭropping steel balls varying in mass from (8-540) g onto the ice Next, the hardness ofĪthletic ice surfaces was analyzed. Ice generally has a rocker value of (20-50) m. The gauge and it was found that the portion of the runner contacting the The size of the device was optimized for hockey, short and long track Performed using a handheld rocker gauge, a device used in speed skating. Was to analyze runners used in the sport of bobsleigh. 3.2b) which calculates theĬoefficient of friction between a steel blade and ice. I would be clear where the configuration of the threads has been defined, and the 1D, 2D and 3D access pattern depends on how you are interpreting your data and also how you are accessing them by 1D, 2D and 3D blocks of threads.The primary objective of this work is to examine the effect of theīobsleigh runner profile on ice / runner friction. To sumup, it does it matter if you use a dim3 structure. Int y = blockIdx.y * blockDim.y + threadIdx.y īecause blockIdx.y and threadIdx.y will be zero. So, in both cases: dim3 blockDims(512) and myKernel>(.) you will always have access to threadIdx.y and threadIdx.z.Īs the thread ids start at zero, you can calculate a memory position as a row major order using also the ydimension: int x = blockIdx.x * blockDim.x + threadIdx.x The same happens for the blocks and the grid. When defining a variable of type dim3, any component left unspecified is initialized to 1. However, the access pattern depends on how you are interpreting your data and also how you are accessing them by 1D, 2D and 3D blocks of threads.ĭim3 is an integer vector type based on uint3 that is used to specify dimensions. The memory is always a 1D continuous space of bytes. The way you arrange the data in memory is independently on how you would configure the threads of your kernel.
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