METHOD FOR DETERMINING THE AERODYNAMIC MOMENT OF RESISTANCE OF A WHEEL

摘要

A method for determining the aerodynamic moment of resistance Maero-EM of a wheel arranged on an axis, by measuring the value of the mechanical power Pm to be applied to the wheel in order to maintain it in rotation at a constant speed ω, the said wheel being equipped with a rotational-drive means and with a device for picking off and/or recording the numerical values of the said mechanical power and those of the rotational speed. The wheel is protected by a removable cap and is subjected to a flow of air.

主权项

1. A method for determining the aerodynamic moment of resistance Maero-EM of a wheel arranged on an axis, by measuring the value of the mechanical power Pm to be applied to the wheel in order to maintain it in rotation at a constant speed ω, wherein the wheel is equipped with a rotational-drive means and with a device for picking off and/or recording the numerical values of the mechanical power and of the rotational speed, comprising:
protecting the wheel by a removable cap, constantly subjecting the wheel to a flow of air, picking off the mechanical power Pm applied to the wheel and the rotational speed ω of the wheel, inputting the picked-off measurements of rotational speed ω and of mechanical power Pm of the wheel into the following mathematical formula:
Pm=ω(Maero-EM+Mf)   (I)where
Pm represents the mechanical power needed to keep the wheel in rotation at a constant speed, ω represents the rotational speed of the said wheel, Mf represents the value of the moment of friction of the hub of the wheel, and Maero-EM represents the aerodynamic moment of resistance of the said wheel.