This paper presents the study of a local exhaust ventilation system with plain (unflanged) and flanged hoods. Centerline velocity and velocity contours in front of exhaust hood openingswere measured and compared to other previously reported results. Centerline velocity correlations are derived for a full range of hood axes. The effect of turbulence intensity and surrounding equipment on the velocity contours is also analyzed. Capture velocity for three different types of contaminant particles (saw dust, wheat flour, and sand) was determined.
The purpose of continuous fan operation is to bring in fresh outdoor air to the conditioned space in order to maintain acceptable indoor air quality. Ventilation not only uses more energy, but it also impacts air distribution system efficiency.This is partially due to various system interactions. The objective of this paper is to quantify the impact of continuous fan operation on energy use and distribution efficiency by introducingtwo new parameters: energy use ratio (EUR) and distribution efficiency ratio (DER).
Velocity and turbulence intensity profiles of the airflow inside a section of a narrow body (737) aircraft cabin were measured using the particle image velocimetry (PIV) technique.In this paper the measurement technique is described and the results are presented and discussed. The purpose of this study was to provide accurate experimental data for validation of the computational fluid dynamics (CFD) codes developed for this application.
This paper gives an overview of sources of indoor particulate matter (PM) and its effects on occupants. Studies indicate that outdoor PM contributes to indoor PM, yet a large fractionof indoor PM is generated indoors. The ratio of indoor to outdoor PM concentrations (I/O ratio) varies substantially due to different indoor conditions and PM spatial distributions.Real-time investigation using multiple point sampling technique is needed for better understanding of PM spatial distribution.
This paper intends to answer the folllowing question : Why a laboratory on Indoor Air technology ?Some good reasons are that the HVAC sector in Norway is facing an increasingly difficult situation :. need of major renovation for schools and hospitals, . limited resources available for research and development in small and medium-sized enterprises.. Number of students graduating from the university with an HVAC degree has been steadity decreasing..
The article discusses the design of the system with heat recovery to be used for the ventilation/air conditioning of a swimming pool building, in which air reaches high temperatures and humidities. The systems described and analysed use heat recovery through air to air heat exchanger or heat recovery through heat exchanger and heat pump.
The purpose of the current study is to compare experimental thermal comfort results with those predicted by the Fanger model. In making this comparison, the uncertainty of the data will be considered along with the uncertainty of the Fanger model predictions based on the uncertainty of the model input parameters. A primary outcome of the study will be a better understanding of the uncertainty associated with thermal comfort predictions. A qualitative comparison illustrates that the Fanger model can predict the experimental results for many of the cases.
This paper presents the main findings of Project HIT.2000.25 supported by the Scientific Research Foundation of Harbin Institute of Technology, a field study of indoor climates and occupant comfort in 66 residential buildings in Harbin, located in northeastern China.
Fountain and Huizenga (1995) conducted a comprehensive literature review of thermal comfort models. Significant advances in thermal comfort modeling have been achieved since that review. The present paper summarizes the advances in thermal comfort modeling for both building and vehicle HVAC applications that have occurred since Fountain and Huizengas literature review. This paper is intended to describe the potential use of these models and to demonstrate their suitability for predicting comfort during complex transient and non-uniform environmental conditions.
This paper focuses on the mathematical modeling of dynamic human thermal comfort under highly transient conditions for automotive applications. A combined physiological and psychological modeling approach was taken. First, the transient environmental and human activity data, plus the
clothing insulation data, were used as inputs to a human thermal model to determine the physiological responses for the vehicle thermal environmental conditions. Secondly, a series
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