A transient model was developed to predict heat and mass transfer between the environment and chickens subjected to partial surface evaporative cooling under various dry to humid, calm to drafty and hot conditions. A factorial experiment composed by 3 air dry-bulb temperatures (tdb) (35, 38 and 41 °C), 2 dew point temperatures (tdp) (21.1 and 26.7 °C) and 3 air velocities (V) (0.2, 0.7 and 1.2 m.s -1 ) was designed to evaluate the physiological responses of the birds subject to thermal stress with and with out use of direct evaporative cooling. Deep body temperature (tb) and surface temperature (tsurf) were measured throughout the tests via telemetry and thermography, respectively. The model predicts tb rise after 50 min of acute heat exposure (Dtb,50), and it can also be used to predict the effects of wetness level (b) and V on Dtb,50. The model provides a convenient, interactive tool for determining Dtb,50 on wetted and non-wetted hens as a function of environmental conditions.
Available at: http://works.bepress.com/richard-gates/60/
This is an ASAE Meeting Presentation, Paper No. 013011