scholarly journals Effects of Season and House Microclimate on Fungal Flora in Air and Broiler Trachea

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 459
Author(s):  
Danijela Horvatek Tomić ◽  
Ivica Ravić ◽  
Anamaria Ekert Kabalin ◽  
Matija Kovačić ◽  
Željko Gottstein ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Indoor Air ◽  
Ammonia Concentration ◽  
Airflow Rate ◽  
Fungal Flora ◽  
Poultry House ◽  
Study Results ◽  
Seasonal Impact ◽  
Microclimate Conditions

Fungi are present in abundance in poultry housing. The aim of the study was to assess the effect of season and microclimate parameters in poultry housing on fungal flora in the air and broiler trachea in commercial fattening conditions. The study was conducted in summer and winter. Study results indicated seasonal impact and association between fungal flora composition in housing air and broiler trachea. However, the total fungal count in housing air was significantly higher in summer and in broiler trachea in winter, both significantly correlated with indoor relative humidity and ammonia concentration. There was no significant correlation between outdoor and indoor air temperature, relative humidity and airflow rate, respectively. Study results suggested that environmental determination of fungi should be accompanied by their determination in broilers. In addition, seasonal impact on fungal contamination should be associated with microclimate conditions in the poultry house rather than the season itself. The fungi detected and the results obtained have implications not only for broiler health but also for the health of humans working in such environments.

Application of an Air-Air Energy Exchanger in a Building HVAC System in Xiamen

2012 ◽  
Vol 170-173 ◽  
pp. 2474-2477
Author(s):  
Li Li ◽  
Qing Ling Zhang ◽  
Ya Ping Li
Keyword(s):  
Relative Humidity ◽  
Indoor Air ◽  
Air Conditioning ◽  
Living Environment ◽  
Operating Conditions ◽  
Total Heat ◽  
Sensible Heat ◽  
Hvac System ◽  
Indoor Temperature ◽  
Study Results

An air-air energy exchanger (AAEE) has been introduced in the literature as a novel energy recovery system that transfers heat and moisture between the ventilation and exhaust air. In this paper, the application of an AAEE in a HVAC system is investigated. The paper discusses the dependency of AAEE performance on ventilation air and indoor and outdoor air conditions, it describes how to control the AAEE in different operating conditions (summer and winter). The suited meteorological conditions of the AAEE in buildings are given. Based on the humidity and temperature data of the typical meteorological year in Xiamen, the temperature distribution statistics throughout the year is studied and the air enthalpy difference is calculated. Combining with the demand of the indoor air conditioning parameters, the applicable hours of different types of AAEE, such as total heat and sensible heat, in Xiamen are analyzed. It is shown that the lower we intend to get the temperature and relative humidity, the more space there will be for the AAEE to work in summer. In winter, for the sensible heat AAEE, the higher indoor temperature we design, the more hours it works, the greater space we will have for heat recovery. But for the total heat AAEE, it will be used longer as the indoor temperature and relative humidity are designed higher. The study results show that the AAEE can be energy-saving and reduce indoor air pollution of modern buildings, improve indoor work and living environment. The result can provide basic principle and referenced data for product improvement and air-conditioning system design.

scholarly journals Relation Between Microclimate and Air Quality in the Extensively Reared Turkey House

2017 ◽  
Vol 40 (1) ◽  
pp. 83-90
Author(s):  
Mario Ostović ◽  
Sven Menčik ◽  
Ivica Ravić ◽  
Slavko Žužul ◽  
Željko Pavičić ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Air Quality ◽  
Relative Humidity ◽  
Air Temperature ◽  
Indoor Air ◽  
Animal Health ◽  
Airflow Rate ◽  
Carbon Dioxide Concentrations ◽  
Bacteria And Fungi

Abstract Good air quality in poultry houses is crucial for animal health and productivity. In these houses, air is generally contaminated with noxious gases and microorganisms, the concentrations of which depend on numerous factors including microclimate. In this case study, the relation between microclimate and air concentrations of noxious gases and microorganisms was investigated in extensively reared turkey house. The study was carried out at a family household in Dalmatia hinterland, Croatia, with 50.3±3.1 turkeys kept in the house during the study period. Air temperature, relative humidity, airflow rate, concentrations of ammonia, carbon dioxide, bacteria and fungi in indoor air were measured three times per month from September to December, in the morning, prior to releasing turkeys out for grazing. Air temperature ranged from 9.73 to 26.98 °C, relative humidity from 63.29% to 75.08%, and airflow rate from 0.11 to 0.17 m/s. Lowest ammonia and carbon dioxide concentrations were measured in September (2.17 ppm and 550 ppm, respectively) and highest in December (4.50 ppm and 900 ppm, respectively). Bacterial and fungal counts were lowest in December (2.51×105 CFU/m3 and 3.27×103 CFU/m3 air, respectively) and highest in September (6.85×105 CFU/m3 and 1.06x105 CFU/m3 air, respectively). Air temperature and relative humidity showed negative correlation with concentrations of noxious gases and positive correlation with air microorganisms (P<0.05 all).

Numerical and Experimental Modeling of Indoor Air Quality Inside a Conditioned Space with Mechanical Ventilation and DX-Air Conditioner

2020 ◽  
Vol 38 (9A) ◽  
pp. 1257-1275
Author(s):  
Wisam M. Mareed ◽  
Hasanen M. Hussen
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Ventilation System ◽  
Thermal Conditions ◽  
Airflow Rate ◽  
Air Conditioner ◽  
Breathing Zone ◽  
Lecture Room ◽  
Ventilation Performance

 Elevated CO2 rates in a building affect the health of the occupant. This paper deals with an experimental and numerical analysis conducted in a full-scale test room located in the Department of Mechanical Engineering at the University of Technology. The experiments and CFD were conducted for analyzing ventilation performance. It is a study on the effect of the discharge airflow rate of the ceiling type air-conditioner on ventilation performance in the lecture room with the mixing ventilation. Most obtained findings show that database and questionnaires analyzed prefer heights between 0.2 m to 1.2 m in the middle of an occupied zone and breathing zone height of between 0.75 m to 1.8 given in the literature surveyed. It is noticed the mismatch of internal conditions with thermal comfort, and indoor air quality recommended by [ASHRAE Standard 62, ANSI / ASHRAE Standard 55-2010]. CFD simulations have been carried to provide insights on the indoor air quality and comfort conditions throughout the classroom. Particle concentrations, thermal conditions, and modified ventilation system solutions are reported.

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