Vehicle Air Conditioning (AC) systems are used in countries that suffer high temperature degrees during the summer season, one of these countries is Iraq. Most passengers suffer manifestations which may lead to Allergic or Respiratory diseases as they inhale polluted air produced by AC systems.
In this study 10 vehicle were selected randomly on the basis of noxious odors emitted from AC systems. Indoor air samples were collected by using impaction method and using Sabouraud's dextrose agar to grow and isolate dominant fungi species accompanied with AC polluted air. Dust particle diameters aggregated in AC filters were measured because the particles work as transporters to carry fungi then get inhaled by the passengers. After isolating and identifying air fungi, frequency, occurrences percentage calculated. The Ganoderma lucidum extract was used as inhibitor agent and antifungal growth by using different concentrations: (10, 15, 20, 25) mg/ml. The results showed that the dominant species air fungi related to AC systems are: Aspergillus niger, Aspergillus flavus, Penicillium and Rhizopus . The highest occurrences percent 80%, and highest frequency percent 33.3% was recorded to Aspergillus niger ,while the lowest occurrences percent 30%, and lowest frequency percent 12.5% was records to Rhizopus . Microscopic examination for dust particles showed that the particles size ranged between (1 μm to 10 μm), and the highest distribution percentage was 43% for particles of less than 5μm in size which are respirable and can cause allergic and respiratory diseases .The Ganoderma lucidum in concentration of 25mg/ml have highly inhibition zone than other concentrations .
The phenomenon of young people frequenting closed cafes spread in Baghdad to smoke hookahs and cigarettes has increased. This phenomenon is associated with unemployment, an increase in leisure time and the deterioration of economic conditions. This phenomenon has an impact on indoor air quality and exposes workers to the risk of exposure to various pollutants, including particulate matter, therefore, we examined some indicators (PM2.5, PM10) IAQ for a month in summer and another month in winter in six different locations in the Rusafa district. PM2.5 and PM10 concentrations, relative humidity (RH) and temperatures were measured using (Multifunction Air Quality Detector BENETECH -China). The results showed an increase in temperatures inside
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This research was conducted to measure the levels of asbestos fibers in the air of some dense sites of Baghdad city, which were monitored in autumn 2019. Samples collection was conducted via directing air flow to a mixed cellulose ester membrane filter mounted on an open‑faced filter holder using sniffer with a low flow sampling pump. Air samples were collected from four studied areas selected in some high traffic areas of Baghdad city, two of them were located in Karkh (Al-Bayaa and Al-Shurta tunnel) and two in Rusafa (Al-Jadriya and Al-Meshin complex), then analyzed to determine concentrations of asbestos. Measuring of levels of asbestos fibers on the filters was carried out via using scanning electron micros
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In recent years, the demand for air travel has increased and many people have traveled by plane. Most passengers, however, feel stressed due to the limited cabin space. In order to make these passengers more comfortable, a personal air-conditioning system for the entire chair is needed. This is because the human body experiences discomfort from localized heating or cooling, and thus, it is necessary to provide appropriate airflow to each part of the body. In this paper, a personal air-conditioning system, which consists of six vertically installed air-conditioning vents, will be proposed. To clarify the setting temperature of each vent, the airflow around the passenger and the operative temperature of each part of the body is investigate
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Shisha smoke represents one of the causes of indoor air pollution. Heavy metals represent the main components in shisha smoke. In this research study, the indoor concentrations of heavy metals in shisha smoke café sites was investigated, samples were taken from two café sites (site1, site 2) which differ in their volume. Site1 volume was 77m3, while site 2 was 437.5m3. Sample were taken by using a low volume sampler (sniffer), and then examined by the Atomic Absorption Spectrometry (AAS). The results showed that indoor air shisha smoke samples for both experimental sites have shown a significant amount of heavy metals as compared with control sampling values. The mean concentration values of (Pb, Zn, Co, Ni, Cr) in site 1 were (11.004,
... Show MoreA novel robust finite time disturbance observer (RFTDO) based on an independent output-finite time composite control (FTCC) scheme is proposed for an air conditioning-system temperature and humidity regulation. The variable air volume (VAV) of the system is represented by two first-order mathematical models for the temperature and humidity dynamics. In the temperature loop dynamics, a RFTDO temperature (RFTDO-T) and an FTCC temperature (FTCC-T) are designed to estimate and reject the lumped disturbances of the temperature subsystem. In the humidity loop, a robust output of the FTCC humidity (FTCC-H) and RFTDO humidity (RFTDO-H) are also designed to estimate and reject the lumped disturbances of the humidity subsystem. Based on Lyapunov theo
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In this paper, an experimental study of the thermal performance for hybrid solar air conditioning system was carried out, to investigate system suitability for the hot climate in Iraq. The system consists of vapor compression unit combined with evacuated tube solar collector and liquid storage tank. A three-way valve was installed after the compressor to control the direction flow of the refrigerant, either to the storage tank or directly to the condenser. The performance parameters were collected by data logger to display and record in the computer by using LabVIEW software. The results show that the average coefficient of performance of hybrid solar air conditioning system (R=1) was about 2.42 to 2.77 and the average p
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In this paper, an experimental analysis of conventional air-cooled and microchannel condensers in automotive vapor compression refrigeration cycle concerning heat transfer coefficient and energy using R134a as a refrigerant was presented. The performance of two condensers and cycles tested regarding ambient temperature which it was varied from 40oC to 65oC, while the indoor temperature and load have been set to be 23oC and 2200 W respectively. Results showed that the microchannel condenser has 224 % and 77 % higher refrigerant side and air side heat transfer coefficient respectively than the coefficients of the conventional condenser. Thus, the COP, in case of using the microchannel
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In Iraq most of the small buildings deployed a conventional air conditioning technology which typically uses electrically driven compressor systems which exhibits several clear disadvantages such as high energy consumption, high electricity at peak loads. In this work a thermal performance of air conditioning system combined with a solar collector is investigated theoretically. The hybrid air conditioner consists of a semi hermetic compressor, water cooled shell and tube condenser, thermal expansion valve and coil with tank evaporator. The theoretical analysis included a simulation for the solar assisted air-conditioning system using EES software to analyze the effect of different parameters on the power consumption of c
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