air & ventilation, environmental

Upload: rahul-netragaonkar

Post on 08-Jul-2018

219 views

Category:

Documents


0 download

TRANSCRIPT

  • 8/19/2019 Air & Ventilation, Environmental

    1/21

    VentilationDr. Rahul Netragaonkar

    Associate Professor

  • 8/19/2019 Air & Ventilation, Environmental

    2/21

    Air of occupied room

    Occupied room air Vitiated air

    Human activity

    Chemical changes CO ! O

    At rest ".# cu ft CO $hr$per person

  • 8/19/2019 Air & Ventilation, Environmental

    3/21

    Air of occupied room

    Physical changes %

    &emperature ' (ody e)pels heat

    Humidity ' *kin ! lung perspiration #""gm vapour$man$day

    Air movement ' Overcro+ding ,O-struction

  • 8/19/2019 Air & Ventilation, Environmental

    4/21

    Air of occupied room

    Physical changes %

    (ody odour ' Perspiration/ -ad oral hygiene/dirty cloths

    (acterial pollution '

    0)haled air % microorganismsDuring conversation/ coughing/ snee1ingtalking/ spitting etc.

  • 8/19/2019 Air & Ventilation, Environmental

    5/21

    Air of occupied room

    Causes %

    Discomfort /efficiency of +ork /

    Headache /dro+siness /ina-ility to concentrate

  • 8/19/2019 Air & Ventilation, Environmental

    6/21

    Indices of thermal comfort

    2. A3R &04P0RA&5R06. A3R &04P0RA&5R0 AND

    H543D3&76.8. COO93N: PO;0R 6 Air temperature/

    humidity and air movement +ereconsidered together and e)pressed asata &hermometer tomeasure the cooling po+er.

    = A dry >ata reading of ? and a-ove/and a +et >ata reading of " anda-ove/ +ere regarded as indices ofthermal comfort.

  • 8/19/2019 Air & Ventilation, Environmental

    7/21

    2. 0@@0C&3V0 &04P0RA&5R06 temperature/ humidity andmovement of the internal air on the sensation of +armth orcold felt -y the human -ody..

    . CORR0C&0D 0@@0C&3V0 &04P0RA&5R06 3mprovementover the 0ffective &emperature 3nde).

    = 3nstead of the dry -ul- temperature/ the reading of the:lo-e &hermometer is used to allo+ for radiant heat.

    = Air temperature/ velocity/ humidity and mean radiant heat.2. 4cARD90 * 4AB3454 A99O;A(90 *;0A& RA&0 6 .

    litres of s+eat e)creted in four hours as the ma)imumallo+a-le s+eat rate compati-le +ith physiological normal

    reaction of acclimati1ed/ healthy young men for repeatede)posures to heat.= 4cArdle has put P *R value of 8 as upper limit of comfort

    1one

  • 8/19/2019 Air & Ventilation, Environmental

    8/21

    Comfort zones

    = Comforta-le thermal conditions are those under +hich aperson can maintain normal -alance -et+een productionand loss of heat/ at normal -ody temperature and +ithouts+eating.

    C orrected effective temperature deg C 2. Pleasant and cool%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    . Comforta-le and cool%%%%%%%%%%%%%%%%%%%%%%%%%%8. Comforta-le%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    . Hot and uncomforta-le%%%%%%%%%%%%%%%%%%%%%%%%%

    . 0)tremely hot%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    ?. 3ntolera-ly hot%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

  • 8/19/2019 Air & Ventilation, Environmental

    9/21

    Predicted four-hour sweat rate(P4SR)

    2.Comfort 1one%%%%%%%%2%8 litres

    .Gust tolera-le%%%%%%%%%8% . 8.3ntolera-le%%%%%%%%%%%%% .

  • 8/19/2019 Air & Ventilation, Environmental

    10/21

    Ventilation

    Definition 6%

    Replacement of vitiated air !control of incoming air +ith regard

    to it s temperature/ humidity !purity.

  • 8/19/2019 Air & Ventilation, Environmental

    11/21

    Ventilation

    *tandards of ventilation6% Cu-ic space% 4in. 8""%8""" cu. ft $hr$per

    Air change% 9iving room% %8 $hr

    ;ork rooms ! Assem-lies ' %? $hr

    @loor space% "%2"" sI. ft.$per

  • 8/19/2019 Air & Ventilation, Environmental

    12/21

    Ventilation

    &ypes of ventilation6%

    &he +ind%

    Natural

    4echanicalNatural

    Perflation Aspiration

    Cross Ventilation

  • 8/19/2019 Air & Ventilation, Environmental

    13/21

  • 8/19/2019 Air & Ventilation, Environmental

    14/21

    Ventilation

    0)haust ventilation ' 3n halls/ auditoriums/3ndustries etc.

    4echanical

  • 8/19/2019 Air & Ventilation, Environmental

    15/21

    Ventilation

    Plenum ventilation ,Propultion '4echanical

  • 8/19/2019 Air & Ventilation, Environmental

    16/21

    Ventilation

    (alanced ventilation ,Com-ination

    0)haust F Plenum

    4echanical

  • 8/19/2019 Air & Ventilation, Environmental

    17/21

    Ventilation

    Air conditioning '

    *imultaneous control of factorsPhysical ! Chemical

    &emperature/ humidity/ movement/

    distri-ution/ dust/ -acteria/ odour ! to)ic gase

    Affect human health

    4echanical

  • 8/19/2019 Air & Ventilation, Environmental

    18/21

    Ventilation

    Place '

    3ndustries / hospitals /

    operation theatre

  • 8/19/2019 Air & Ventilation, Environmental

    19/21

    Process '

    vapoursaturation

    distri-ution

    @ilter

    heatingat desired temperature

    removal of e)cess moisture

  • 8/19/2019 Air & Ventilation, Environmental

    20/21

    Air conditioning

    Difference in Outside temp ! inside temp J "KC

    Desira-le ' 2" ' 2 KCTransition room – or !cclimati"ation3f temperature difference is large -et+een outside

    atmosphere and air conditioned room/

  • 8/19/2019 Air & Ventilation, Environmental

    21/21