Wind-tunnel transient concentration data were obtained from modeling tests which reproduced gaseous dispersion from five different forty cubic meter or less liquefied natural gas (LNG) spills performed at China Lake Naval Weapons Center. Comparisons in the transient concentration data between these modeled tests and the field tests indicated which parameters are dominant in the modeling process. Model tests which reproduced the wind shear and turbulence...

An experimental study of techniques for modifying the surface shear stress, both mean and fluctuating, in turbulent boundary layers is reported. The surface shear along the test section of a 45.7 cm square wind tunnel, with a downstream expansion section, was determined by means of surface-hot-wire-heat-transfer-gauges. Turbulent boundary layers in both zero and adverse pressure gradients were evaluated.

Accurate, quantitative analysis of ecosystems is dependent on the quality of data used to describe the environment. Data quality is a major concern for the Multi-resource Management Planning Research Project, referred to as the Beaver Creek Project, administered by the Rocky Mountain Forest and Range Experiment Station. The goals of the Beaver Creek Project are centered on development and testing of methodologies for management decision making in...

Soil erosion by rainfall is one of the major sources of sediments transported into streams. The physical processes governing rainfall erosion are very complex and no generally accepted sediment transport equation has been developed so far. Various approaches have been used in the past decades to analyze sediment transport by overland flow.

A simulated atmospheric boundary layer flow over the Renaissance Center model was established whose characteristics compared favorably with the expected flow over the Detroit area. Flow visualization showed fluctuating separation features at certain locations on the center hotel structure and on the elevator towers of office buildings suggesting high values of pressure coefficient in those regions.

Visual and concentration measurements were made for a large number of continuous ground-level releases of heavy gases into a wind-tunnel boundary layer. These different plumes were not affected by any topographic or building wake influences. The experiments provided a broad coverage of the variable range of source gas specific gravity, source gas flow rate, and approach flow wind speed.

Rural transportation systems are of major importance to the nation's economy. Safety of rural bridges in many cases has deteriorated to a dangerous level rendering many avenues for the movement of goods and people to an unusable state. The recently developed glulam bridge system, composed of laminated stringers and deck fastened together by bolted and doweled connections, offers great potential in needed national bridge replacement programs.