Heat transfer efficiency/capability. better. less. Ethylene glycol has superior heat transfer efficiency due to lower viscosity - but more fluid must be circulated to transfer the same amount of energy since Propylene glycol has higher specific heat. Viscosity.
Rotaries, still in use in some parts of the country, are typically larger circles through which vehicles move at higher speeds, while neighborhood traffic circles are typically smaller than roundabouts, and used primarily to calm traffic. In a roundabout, there is no need to change lanes to exit, and traffic moves in a counterclockwise direction. A roundabout also has geometry that forces slower speeds and features islands at the approaches and yield signs. Here are instructions from the Federal Highway Administration on how to use a roundabout:
Another way of looking at roundabouts. Turns that occur at roundabouts can be described by imagining the roundabout to be a clock face. Any turn that exits the roundabout before 12 o'clock can be considered a left turn. Any turn that exits after 12 o'clock can be considered a right turn.