Abstract
In order to try to make the design and the control of thermal radiant environment within livestock barns most suitable, effects of different factors on radiant environment need to be clarified. The authors made the computer program for calculating thermal radiant heat in a gable roofed open-type barn and then carried out an analysis of factorial effects. These procedures are described in this paper and a summary of those is shown below.
The main parts involved in the present program were weather condition, radiant-interchange configuration factors, ground surface temperatures, outside and inside roof surface temperatures, and downward radiant heat in the barn (Fig. 2).
An analysis of factorial effects was conducted by using a response analysis method in “design of experiments” techniques. The factors in the present analysis were (1) the resistance of total heat transmission for the roof, (2) the absorptivity of the outside roof surface for short-wave radiation, (3) the emissivity of the outside roof surface for long-wave radiation, (4) the absorptivity of the inside roof surface, (5) the emissivity of the inside roof surface, (6) the kinds of ground surfaces, (7) the length of the barn, (8) the width of the barn, (9) the height of the eaves, (10) the orientation of the barn, and (11) the inclination of the roof. The values at three levels were given to each factor (Table 5) and numerical simulations for the radiant heat were conducted with the combinations obtained by the table of orthogonal arrays L81 (340). An analysis of variance (ANOVA) for the radiant heat obtained by the simulation will make it possible to evaluate the significance and contribution ratios of factorial effects. And a equation that consists of arithmetic sums of several significant factorial-effects will be able to predict the radiant heat in different barns (eq. (39)).
The results of ANOVA will be discussed in detail in following papers.
