Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 2

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available remote Air distribution in clean rooms
EN
Development of new technologies (microelectronics, computer technology, medicine etc.) demands availability of high-precision technological rooms, named "clean rooms". That is why, demands for keeping necessary microclimate and, as a result, maintenance of effective air exchange organization are constantly rising. In clean rooms there are three basic schemes of air exchange according to Federal Standart of the USA F209C depending on their purpose: 1 - with vertical air jets (from top to bottom); 2 - with horizontal (air supply from whole surface of ceiling or wall ); 3 - with vertical and horizontal air jets. Last one is the most spread for clean rooms with clean degree. Experimental investigations of air jets were carried out on the module of clean room 0,65x3,8x2,4(h)m as a basic unit of clean rooms creation with various volume and different purpose at presence and absence of the equipment. Air was supplied through filters of careful purification, mounted on the wall of equal air distribution pipe with directing blades. Air exhaust was realised through the side hole by width 0,6m and various height in the wall over the floor. Measurement of air jet's velocity was made by thermoelectrical anemometer TA-9 at its numbers 0-5m/s. For obtaining universal calculating equations the air jet's velocities have been expressed as sizeless. Air outlet velocity from incoming hole Vo and air jet's velocity epures in clean room module have been determined without any equipment and with it, taking into account different places of air exhaust devices; dependences of air jet's sizeless velocities have been obtained at the conditions described above; corrective coefficient, which takes into account different places of the equipment, has been determined; non-ventilated areas have been established at these conditions. Velocity of incoming air outlet Vo was determined under condition of minimum air velocity maintenance in service area of clean room module; obtained equations make possible to establish recommended places of the technological equipment situation at the initial input parameters.
2
Content available remote Air distribution and air jet's acoustic properties
EN
Relation between such factors as a noise level, air flow rate and incoming hole size were considered. The aim of investigations is to obtain the chart and analytic equations for determination of the necessary incoming hole size (diameter or width and height) under condition of the necessary amount of air satisfaction at the rated noise level. Experimental research of the acoustic phenomena at the air jets leakage from flat and round outlets was carried out in room 12,0x6,0x3,0 (h) m. Air was supplied at the various flow rate both through a flat incoming hole by variable width (200 - 600mm), height (10 - 60mm) and through a round outlet by various diameter (100 - 400mm). Air exhaust was realised through a side hole by diameter 250mm in a wall under a ceiling. Measurement of the air jet's velocity was made by thermoelectrical anemometer TA-9 at its numbers 0—5m/s. The noise level was measured by noisemeter SHM-1-MI and vibration of air pipes' metal walls - by vibrometer DN-3-MI. Three noise sources were taken into account, namely: fan, vibration of air pipes' metal walls and aerodynamic noise at the air jet's leakage. For obtaining universal calculating equations width, height and diameter of the outlets were expressed as sizeless. Air jet's initial velocity Vo at leakage from different size and shape incoming holes, noise level and vibration of air pipes' metal walls have been measured; the chart, that shows relation between such factors as a noise level, air flow rate and incoming hole's size of both shapes (flat and round), has been created; obtained chart has been approximated by equation for analytic calculation. Represented data gives a possibility to determine air distribution units' size under maintenance of the rated noise level, when necessary air amount is supplied, and is considered as a base for designing air conditioning system.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.