Today we went for a highway trip. There was a crosswind of about 30 MPH coming at our driver's side most of the time. On the way home there was a lesser breeze blowing at I think the right front corner of the Prius. When I got home I checked the consumption on the computer. It was reading about 3 MPG less than the last time I drove the same road & same speed. Can someone tell me how much wind affects the MPG? I know there is resistance, but this is new to me. Thanks. :huh:
Wind direction and speed plays a huge effect. From a Palm Application called "Prius Synergy Simulator" A Prius going 55 mph and a head wind of 30 mph will have a 57.3% aero component resulting in a calculated 31.1 mpg. On the other hand the same as a tail wind will have a 69.84 mpg result. Wind speed and direction does have a sizeable effect depending on the speed of the Prius and the speed and direction of the wind. You can view information about this program at: Prius Synergy Simulator I am currently beta testing this program for the author. As you can see from the web site the program is quite comprehensive. Hope that helps. Cheers p.s. other variables entered into the program to arrive at the above results were based on my location, temperature, humidity, elevation, barometer, load, tires, etc which are all accounted for in the above program.
Just the data displayed here is most illuminating: very impressive - thanks. Any chance there will be a Windows version of the program in the future? Good luck for its success. Will it be released as a commercial program? C
I, too, am beta testing the public version of this program. It's unlikely there'll be a Windows version, but there are PDA emulators for PC available so it can be run on a PC. It will be released as a commercial program...probably fairly soon.
Hi Walker1, Yes crosswinds from slightly to the front or further forward increase wind drag. The car is designed for front-back airflow. When there is a cross wind, the vehicle sees the front-back wind, sumed with the cross wind. The resulting wind flows a little sideways across the car, and the distance the wind is in contact with the car is longer as the distance from the front left (for example) to the rear right (for example) is longer than from the front tip to the rear tip. This creates more of what is called friction drag. As the wind is now not flowing in the designed optimum path over the car, the air tumbles more as it comes off the car. This results in more of what is called form drag. Thirdly, the total car airspeed is more than if there was no side wind.
I can attest that "crosswinds" have a profound effect on MPG's. My Holiday roundtrip to see my extended family members was a 750-mile triangle: Dallas South to Houston; Houston West to Kingsland (West of Austin); Kingsland North to Dallas. The South leg MPG was 52.1 MPG with a ~15 mph headwind; The West leg MPG was 40.5 MPG with a ~30 MPH South wind off the Gulf of Mexico; The North leg MPG was 54.5 MPG with positive wind effect - ~10 MPH help from the South. Surprised me, but a crosswind does have a strong effect on MPG.
