Models are defined for various mixing conditions, in continuous flow systems. Differential equations are derived which take into account aneffective volume of mixing, possible short-circuiting, hold-up time of the system, partial displacement or piston flow. The values of the different factors contained in the integrated equations can be determined experimentally by the particular response of a given system to a sudden change in composition of the feed. A correlation of the effective volume of mixing and the agitator r.p.m. is presented.

A systematic series of tests measuring probable distribution of wind pressure on buildings over a practically useful range of building proportions was undertaken using a three dimensional tunnel on a wide assortment of simply gabled block type structures. These tests were then extended to thinwalls, hangar type structures, and simple building groups. The possible effects on building codes and construction techniques are discussed.

This paper discusses the flow of air around ideal (cubic) structures on plane surfaces subjected to a turbulent boundary layer wind. These winds are shown to follow a power-law variation with height, while winds significantly effected by thermal stratification follow a log-linear distribution. Discussion of stagnation zones, flow separation, and pressure changes is included, with possible effects upon air quality and infiltration. Also discussed are variations in building design and addition of neighboring buildings, both which produce very complex winds, yet to be quantized.

The objectives of this review are to establish an initial subject-matter base for wind engineering, to demonstrate current capabilities and deficiencies of this base for an engineering treatment of wind-effect problems, and to indicate are

Three identical houses in Houston, Texas were extensively instrumented for measuring their air conditioner energy consumption and ceiling and duct heat-gain rates. Comparative tests were conducted to investigate differences in house performance due to increased attic ventilation. The performances of a roof-mounted power ventilator, a ridge vent, and wind-driven turbines were compared to the performance of soffit venting meeting the requirements of the HUD Minimum Property Standards.

An analysis of ventilation necessary to maintain air quality in an above-ground fallout shelter was done, making use of theoretical models, and generalizing the results to fit measurements on actual shelter data. Results show that, at most, boundary surface heat loss serves as a safety factor for ventilation systems, and thus ventilation systems should be designed to remove the entire thermal load generated within the shelter. This, when considered in addition to weather and load expectations, establishes an upper limit on ventilation equipment size.

This paper describes part of a research on the influence of environment on physiological reactions and thermal comfort. Experimental rooms and apparatus are described and the imperfections in some of the instrumental methods - especially in respect to the measurement of air change by tracer substances - are noted. A brief description of a method to measure air change is givenin which CO2 is used. The importance of limiting the rate of air change in rooms heated by fires - as a means to save heat - is stressed.

Describes validation of a simple technique for infiltration measurement in large, multicelled, naturally ventilated buildings by reference to a computer model study and by field measurements in two naturally ventilated office buildings. The salient features of the technique are: 1) a single tracer gasis used, 2) measurements need only be carried out in part of the building, 3) an initially uniform distribution of tracer is not needed, and 4) artificial mixing of the tracer with the internal air is not essential.

Air leakage characteristics of 192 new windows installed in new residential construction representative of those units commonly installed in the Minneapolis/St. Paul Metropolitan Area have been measured and evaluated. The tested windows represented all major operation types, window material types and manufacturers represented in this market segment. The air leakage data obtained in the field were compared to industry and government standards and manufacturers reports for reference.