Airflow and heat flux through the vertical opening of buoyancy-induced naturally ventilated enclosures

Thermography and Sonic Anemometry to Analyze Air Heaters in Mediterranean Greenhouses

“…From the inside humidity data recorded by the fixed sensors, we can obtain the specific humidity ( q ) and correct the sonic anemometer temperature ( T SC , °C) using the following expression [24]: $T_{sc}=\frac{T_s}{1+0.51q}$To improve the accuracy of this correction of the sonic temperature a humidity sensor would be required together with each ultrasonic anemometer, measuring the air humidity at the same points as the sonic temperature is measured.…”

Sonic anemometry and sediment traps to evaluate the effectiveness of windbreaks in preventing wind erosion

“…ized increase in the airflow energy, which is probably due to the increase in velocity as the air overcomes the barrier (Table 6). The macroscale represents the dimension of the most energetic eddies that have a significant effect on the air mixture and therefore on ventilation (Tanny et al, 2008). There was an overall reduction in the value of the macroscale (larger eddies, with more energy and greater capacity to transport particles) at heights of 0.4 and 0.7 m. This behavior is of great interest to reduce wind erosion.…”

Effectiveness of horizontal air flow fans supporting natural ventilation in a Mediterranean multi-span greenhouse

“…The term η T represents the effectiveness in eliminating the heat from the area of the greenhouse occupied by the crop. When the air inside the greenhouse mixes perfectly then η T = 1 (Tanny et al, 2008). For the first test, without fans but with moderate wind velocity, η T was 0.95.…”

“…Therefore, in humid air it is necessary to correct the sonic temperature of air T S [ºC] obtained by the 3D sonic anemometer with the speed of sound. The specific humidity q [kg kg -1 ] was used to calculate the corrected sonic temperature T SC [ºC] using the following expression (Tanny et al, 2008): ( )…”

“…This term can be calculated with the inside temperature of the greenhouse and with the temperature of the air leaving through the vents as follows (Qingyan et al, 1988;Tanny et al, 2008): where: T ov is the average temperature of the air going out through the vents and ∆T io is the difference between inside and outside temperature during the measurement test. The term η T represents the effectiveness in eliminating the heat from the area of the greenhouse occupied by the crop.…”