Performance test of PSA-type O2 separator for efficient O2 supply to room ventilation system combined with CO2 adsorption module

In Vietnam, the operating room (OR) is used with max productivity. So, how to maintain comfort environment level, which is one of the assignments in designing and installing the operating room. In this study, the OR model is designed based on ASHRAE 170 – 2013 standard [1], and dimensions are referred to as “Comparison of Operating Room Ventilation System in the Protection of the Surgical Site” [2]. ANSYS CFX is used for calculating and simulating velocity and temperature of surveyed air points inside the room by many cases. A face temperature between 20,3 and 20,6 °C and a velocity of around 0,15 to 0,18 m/s is provided from the same laminar diffuser array. From the results, the OR comfort level is reviewed through the ADPI index.

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Tracking the Flu Virus in a Room Mechanical Ventilation Using CFD Tools and Effective Disinfection of an HVAC System

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132520500194 ◽

2020 ◽

Vol 28 (02) ◽

pp. 2050019

Author(s):

Ali Hasan

Keyword(s):

Mechanical Ventilation ◽

Ventilation System ◽

Scientific Data ◽

World Health ◽

Mechanically Ventilated ◽

The Status ◽

Air Disinfection ◽

Room Ventilation System ◽

Health Organization ◽

Airborne Viruses

Recent concerns raised by the World Health Organization over the Coronavirus raised a worldwide reaction. Governments are racing to contain and stop the Coronavirus from reaching an epidemic/pandemic status. This research presents a way in tracking such a virus or any contagious germ capable of transferring through air specifically where such a transfer can be assisted by a mechanical room ventilation system. Tracking the spread of such a virus is a complicated process, as they can exist in a variety of forms, shapes, sizes, and can change with time. However, a beginning has to be made at some point. Assumptions had to be made based on published scientific data, and standards. The tracking of airborne viruses was carried out on the following assumption (for illustrative purposes); one person with one sneeze in a period of 600 s. The presence of viruses was tracked with curves plotted indicating how long it could take to remove the sneezed viruses from the mechanically ventilated room space. Results gave an indication of what time span is required to remove airborne viruses. Thus, we propose the following: (a) utilizing CFD software as a possible tool in optimizing a mechanical ventilation system in removing contagious viruses. This will track the dispersion of viruses and their removal. The numerical solution revealed that with one typical adult human sneeze, it can take approximately 640 s to reduce an average sneeze of 20,000 droplets to a fifth; (b) upscaling the status of human comfort to a “must have” with regards to the 50% relative humidity, and the use of Ultraviolet germicidal irradiation (UVGI) air disinfection in an epidemic/pandemic condition. A recommendation can be presented to the local authorities of jurisdiction in enforcing the above proposals partially/fully as seen fit as “prevention is better than cure”. This will preclude the spread of highly infectious viruses in mechanically ventilated buildings.

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A new modelling procedure of the engine room ventilation system for work risk prevention and energy saving

Proceedings of the Institution of Mechanical Engineers Part M Journal of Engineering for the Maritime Environment ◽

10.1177/1475090216687148 ◽

2017 ◽

Vol 231 (4) ◽

pp. 863-870 ◽

Cited By ~ 1

Author(s):

José A Orosa ◽

Ángel M Costa ◽

José A Pérez

Keyword(s):

Energy Saving ◽

Ventilation System ◽

Three Dimensional ◽

Thermal Conditions ◽

Pollution Reduction ◽

Dynamics Model ◽

Engine Room ◽

Efficient Control ◽

Room Ventilation System ◽

Time Required

Maritime transport is one of the primary international objectives for energy saving and pollution reduction, in agreement with the International Maritime Organization. Within the most interesting energy-saving topics, the ventilation system of the engine room must be highlighted, which represents about 5% of the nominal power of a modern ship. Nevertheless, its energetic optimization is not simple and must consider also work risk criteria, since the engine room is the hottest and, in consequence, one of the hazardous places in the ship. In this research, a complete three-dimensional computational fluid dynamics model of the engine room of a real ship has been developed in order to identify the hottest places and fully characterize their thermal conditions. On the basis of this analysis, a mathematical model of the maximum working time allowed has been defined, which can be directly used to design an efficient control algorithm for the ventilation system. In a complementary way, the minimum time required to rest in the control engine room to release the cumulated heat has also been analysed, in order to optimize its set-point conditions.

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Solar Powered Mechanical Ventilation: A case study

E3S Web of Conferences ◽

10.1051/e3sconf/201911101058 ◽

2019 ◽

Vol 111 ◽

pp. 01058

Author(s):

Aslı Birtürk ◽

Orhan Ekren ◽

Sinan Aktakka ◽

Özdem Özel ◽

Macit Toksoy

Keyword(s):

Mechanical Ventilation ◽

Solar Energy ◽

Performance Test ◽

Ventilation System ◽

Test System ◽

Photovoltaic System ◽

Airflow Rate ◽

Technical Problems ◽

Photovoltaic Panels ◽

Solar Powered

In this study, a solar powered mechanical ventilation unit has investigated and tested in terms of efficiency and performance. Test unit can be divided into two parts, the first one is ventilation unit with 370 m3/h max airflow rate and max 167 W fan power provides fresh air for a residency and recovers heat from the climatized exhaust air. Total area is 70 m2 for the residency and total occupant is four. The second part of the test system is solar energy power system with two 325 W polycrystalline photovoltaic panels, an inverter and two batteries. The mechanical ventilation unit has energized by a solar photovoltaic system; if the solar energy is not available then ventilation unit has connected to the national electricity grid. This is an alternative option to consumers to use electricity by the grid in case the PV system does not produce enough energy because of the usage or the technical problems or the weather conditions based on the seasons. On the other hand, in some cities, number of photovoltaic panels rolled up upper number according to solar energy potential and therefore resulted excess electricity has assumed to sell to the national grid. According to the results, the test system is able to operate at maximum ventilation necessity and power consumption without grid connection in Izmir. Furthermore, we have compared Izmir and Romania in accordance with feasibility for the same mechanical ventilation system at max flow rate and required ventilation rate is determined depends on daily usage scenario of the room.

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EKSPERIMENTINIO ŠILUMOS SIURBLIO CIKLO VALDYMO ALGORITMO PAIEŠKA / EXPERIMENTAL STUDY OF THE HEAT PUMP CYCLE CONTROL ALGORITHM SEARCH

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2019.10583 ◽

2019 ◽

Vol 11 (0) ◽

pp. 1-5

Author(s):

Anton Frik ◽

Dovydas Rimdžius ◽

Tomas Kropas

Keyword(s):

Heat Pump ◽

Air Temperature ◽

Ventilation System ◽

Experimental Tests ◽

Outdoor Air ◽

Control Logic ◽

Experimental Heat ◽

Expansion Valve ◽

Room Ventilation System ◽

Compressor Power

This paper analyzes an experimental heat pump used for heat recovery in a mechanical room ventilation system. The aim of the work is to examine the operation, control logic of the heat pump and evaluate the possibilities of its operation modes, cycle control by outdoor air temperature. A review of scientific literature and experimental tests of the heat pump were performed to achieve this goal. Tests were performed in three stages, after each stage, according to the results obtained the heat pump stand was improved and experimental modes were adjusted. During the experiment, the tendencies of the heat pump freon and air involved in the heat exchange parameters are analyzed with different combinations of expansion valve positions and compressor power. Knowing these experimental characteristics, the extent to which the combination of these two controls can be used to efficiently control of the heat pump according to the outside air temperature is assessed. Based on the results of the research the heat pump control algorithms (depending on the variable outdoor air temperature) are prepared.

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