Sprinkler and Fan Cooling System for Dairy Cows in Hot, Humid Climates

1989 ◽  
Vol 5 (2) ◽  
pp. 231-236 ◽  
Author(s):  
J. T. Strickland ◽  
R. A. Bucklin ◽  
R. A. Nordstedt ◽  
D. K. Beede ◽  
D. R. Bray
2014 ◽  
Vol 722 ◽  
pp. 182-189
Author(s):  
Li Gang Ma ◽  
Chang Le Xiang ◽  
Tian Gang Zou ◽  
Fei Hong Mao

The paper proposes a cascade control strategy of speed feedback in inner loop and temperature feedback in outer ring for hydro-viscous driven fan cooling system, and compares the simulation of PID and fuzzy PID. The simulation result shows that the double-loop control system while the response time longer, but much smaller overshoot, can achieve a good feedback to adjust the fan speed and temperature and realize stepless speed regulation of hydro-viscous driven fan cooling system under the premise of stability for fan speed and system temperature.


Author(s):  
Dong-Il Kim ◽  
Ki-So Bok ◽  
Han-Bae Lee

To seek the fan operating point on a cooling system with fans, it is very important to determine the system impedance curve and it has been usually examined with the fan tester based on ASHRAE standard and AMCA standard. This leads to a large investment in time and cost, because it could not be executed until the system is made actually. Therefore it is necessary to predict the system impedance curve through numerical analysis so that we could reduce the measurement time and effort. This paper presents how the system impedance curve (pressure drop curve) is computed by CFD in substitute for experiment. In reverse order to the experimental principle of the fan tester, pressure difference was adopted first as inlet and outlet boundary conditions of the system and then flow rate was calculated. After determining the system impedance curve, it was compared with experimental results. Also the computational domain of the system was investigated to minimize computational time.


2008 ◽  
Author(s):  
Mohamed Samer ◽  
Hartmut Grimm ◽  
Mohamed H Hatem ◽  
Reiner Doluschitz ◽  
Thomas Jungbluth
Keyword(s):  

2017 ◽  
Vol 48 (1) ◽  
pp. 21-27 ◽  
Author(s):  
Simona M.C. Porto ◽  
Alessandro D'Emilio ◽  
Giovanni Cascone

Among the causes that influence cow welfare, heat stress induced by microclimatic conditions is one of the most relevant and many studies have investigated the efficacy of different cooling systems on animal health status. Nevertheless, the direct influence of the cooling systems on possible modifications of dairy cow behaviour has been addressed in a few studies and the related results were affected by the presence of a paddock, which gave a refuge from hot temperature. Since an alteration of the daily time budget spent by dairy cows in their usual activities can be associated with changes in their health status, this study investigated the effects of the alternation of two different cooling systems on lying, standing, and feeding behaviour of a group of dairy cows bred in a free-stall dairy house where animals had no access to a paddock. The barn was equipped with a fogging system associated with forced ventilation installed in the resting area and a sprinkler system associated with forced ventilation installed in the feeding area. The two systems were activated alternately. The results demonstrated that the management of the two cooling systems affected the analysed behaviours. Though the activation of the cooling system installed in the resting area encouraged the decubitus of animals in the stalls, the activation of that one of the feeding alley could not be able to influence the standing behaviour and had only a moderate positive influence on the feeding activity.


2012 ◽  
Vol 57 (2) ◽  
pp. 299-306 ◽  
Author(s):  
Cristiane Gonçalves Titto ◽  
João Alberto Negrão ◽  
Evaldo Antonio Lencioni Titto ◽  
Taissa de Souza Canaes ◽  
Rafael Martins Titto ◽  
...  

1992 ◽  
Vol 8 (2) ◽  
pp. 251-256 ◽  
Author(s):  
L. W. Turner ◽  
J. P. Chastain ◽  
R. W. Hemken ◽  
R. S. Gates ◽  
W. L. Crist
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document