scholarly journals STATISTICAL CONSIDERATIONS WHEN USING HYSTERESIS TO ESTIMATE INTERNAL HEAT LOAD IN DAIRY COWS

2012 ◽  
Author(s):  
S. Maynes ◽  
A. M. Parkhurst
Keyword(s):  
Dairy Cows ◽  
Heat Load ◽  
Internal Heat

Effects of the daily heat load duration exceeding determined heat load thresholds on activity traits of lactating dairy cows

2018 ◽  
Vol 77 ◽  
pp. 67-74 ◽  
Author(s):  
Julia Heinicke ◽  
Gundula Hoffmann ◽  
Christian Ammon ◽  
Barbara Amon ◽  
Thomas Amon
Keyword(s):  
Dairy Cows ◽  
Heat Load ◽  
Load Duration ◽  
Lactating Dairy Cows

Modeling the Applicability of a Displacement Ventilation System

2021 ◽  
Vol 11 (1) ◽  
pp. 63-89
Author(s):  
Edgar C. Ambos ◽  
Evan Neil V. Ambos ◽  
Lanndon A. Ocampo
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Heat Load ◽  
Ventilation System ◽  
Internal Heat ◽  
The Philippines ◽  
Airflow Rate ◽  
Displacement Ventilation ◽  
Tropical Country

Due to its significant role in improving indoor air quality, displacement ventilation system is widely adopted in current literature. This paper proposes a displacement ventilation system for room conditions with ceilings that are relatively low, internal heat load could be high, walls could be sunlit, and occupants doing the low physical activity. These conditions are prevalent in the Philippines, being a tropical country. Input parameters to the design process such as heat load, the height of the ceiling, comfort, and indoor air quality requirements were generated, and the main output parameters are the stratification height and ventilation airflow rate. To demonstrate the proposed displacement ventilation system, four cases were generated. Results show that the ventilation airflow rates obtained from the four cases were greater than the minimum outdoor air requirements for health in conference rooms and large assembly areas which are 17.5 and 3.5 liters/sec*person respectively, for smoking and no smoking rooms.

scholarly journals The effect of food location, heat load, and intrusive medical procedures on brushing activity in dairy cows

2013 ◽  
Vol 96 (10) ◽  
pp. 6506-6513 ◽  
Author(s):  
R. Mandel ◽  
H.R. Whay ◽  
C.J. Nicol ◽  
E. Klement
Keyword(s):  
Dairy Cows ◽  
Heat Load ◽  
Medical Procedures ◽  
Food Location ◽  
Effect Of Food

A Comparison of the Relative Effectiveness of Fin Aspect Ratio Under Natural Convective Heat Transfer With Top Mounted Fins

2009 ◽  
Author(s):  
Anthony S. Pruszenski
Keyword(s):  
Natural Convection ◽  
Aspect Ratio ◽  
Heat Load ◽  
Relative Effectiveness ◽  
Internal Heat ◽  
Maximum Temperature ◽  
Constant Heat ◽  
Aspect Ratios ◽  
Square Plate ◽  
Base Width

Mechanical engineers often design fins on metal enclosures to dissipate an internal heat load using natural convection. This paper gives the results of a series of CFD (Computational Fluid Dynamics) studies, and, supporting calculations for the maximum temperature rise on a plate with a constant heat load of 100 watts applied to the bottom of the plate. Vertical fins are formed on the top surface of the plate. In this study, the horizontal dimensions and thickness of a square plate are held constant, while, the aspect ratio of the top surface fins are varied between studies. The aspect ratio is defined as the ratio of the height of the fin to the width of the base of the fin. The study compares aspect ratios from 1:1 to 40:1 with a constant base width. In addition, comparisons between 20:1 aspect ratio fins with the same height but with different fin counts due to changes in fin separation distances are compared. Closely spaced fins are not always the best solution for natural convection.

scholarly journals Evaluation of thermal stress indexes for dairy cows in tropical regions

2007 ◽  
Vol 36 (4 suppl) ◽  
pp. 1192-1198 ◽  
Author(s):  
Roberto Gomes da Silva ◽  
Débora Andréa Evangelista Façanha Morais ◽  
Magda Maria Guilhermino
Keyword(s):  
Dairy Cows ◽  
Heat Load ◽  
Selection Criterion ◽  
Equivalent Temperature ◽  
Temperature Index ◽  
Tropical Regions ◽  
Heat Load Index ◽  
Humidity Index ◽  
Index Value ◽  
Jersey Cows

Data from 359 Holstein and 54 Jersey cows (total of 1359 observations) collected in commercial herds in the northeast of Brazil were used to evaluate six environmental stress indexes. The selection criterion was the correlation between the index value with the rectal temperature (RT) and the respiratory rate (RR) of cows. Both Temperature-Humidity Index (THI) and Black Globe-Humidity Index (BGHI) had the lowest correlations with animal RT and RR. The selected indexes were the Equivalent Temperature Index (r = 0.293 and 0.520 with RT and RR, respectively) and the Heat Load Index (0.286 and 0.542, respectively).

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