Determination of Heat and Momentum Fluxes Over Baghdad City
Keywords:Momentum flux, Heat flux, Obukhov length, Stability.
AbstractIn this study heat and momentum fluxes have been determined at Al-Mustansiriyah University, Baghdad, Iraq, by using eddy correlation method. It is one of the methods which determines heat and momentum fluxes and it is considered direct and accurate. This method depends on high response instruments like Ultrasonic Anemometer (model: 1590- PK- 020) which is used in this study. Observation period is about 53 days for 24 hours in months June, July and August from 15/06/2016 to 06//08/2016 and the observations included wind speed and temperature every second. MATLAB program has been used to process huge data to calculate heat and momentum fluxes (H and ). The maximum value of H equals 127.6 Wm-2 in 10:30 at 26/07/2016 and minimum value equals -58.9 Wm-2 in 07:30 at 29/06/2016, as well, the maximum value of equals 0.134535 Nm-2 in 15:00 at 03/08/2016 and minimum value equals -0.4649 Nm-2 in 03:00 at 01/07/2016. It is found that there is an inverse relationship between H and. Also maximum frequency of friction velocity at unstable conditions.
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