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. 2023 Apr 3;9(4):e14807. doi: 10.1016/j.heliyon.2023.e14807

Table 4.

Energy calculation expressions for inclined solar still with baffles [39,43].

Convective mode is used to transmit heat from the glass cover to the water.
  • Qc,wg=hc,wg(TwTg) (1)

  • hc,wg=0.884[(TwTg)+{(pwpg)Tw268.90×103pw}](1/3) (2)

Heat transfer through radiative mode with glass cover and water
  • Qr,wg=hr,wgAw(TwTg) (3)

  • Qr,wg=εeffectiveσAw(Tw4Tg4) (4)

  • hr,wg=εeffectiveσ(Tw2+Tg2)(Tw+Tg) (5)

Evaporation enables the glass cover's water can lose heat.
  • Qe,wg=(16.237x103)hc,wgAw(pwpg) (6)

  • Qe,wg=he,wgAw(TwTg) (1)

  • he,wg=16.237x103hc,wg[pwpgTwTg] (7)

  • me,wg=(Qe,wghfg)×3600 (8)

Heat exchange between the ISSB's glass cover and outside air
  • Qga=Qc,ga+Qr,ga (9)

  • Qr,ga=hr,gaAg(TgTa) (10)

  • Qr,ga=εgσAg(Tg4Tsky4) (11)

  • hr,ga=εgσ[Tg4Tsky4]TgTa (12)

  • Qc,ga=hc,gaAg(TgTa) (13)

  • hc,ga=5.7+3.8Va (for velocity of wind<5 m/s) (14)

Balance of energy in the ISSB's still basin
  • (αb)AbI=Qc,bw+Qloss (15)

  • Qc,bw=hc,bwAb(TbTw) (16)

  • Qloss=UbAb(TbTa) (17)

  • Tb=(αb)I+hc,bwTw+UbTahc,bw+Ub (18)

Energy balance of the glass surface
  • αgI=h3(TgTa)h2(TwTg) (19)

  • h2=hr,wg+he,wg+hc,wg (20)

  • h3=hr,ga+hc,ga (21)

  • Tg=[αgI+h2Tw+h3Tah2+h3] (22)

Energy balance of water outlet temperature
  • Iτg(1αw)nxy=mfwCpw(ToutTin)(xdydxdy)nxyQbaffle (23)

  • Tout=nxy[Qbaffle+Iτg(1αw)mfCpw(xdydxdy]+Tin (24)

  • TW=Tin+[nxy[Iτg(1αw)+Qbaffle]2mfwCpw(xdydxdy)] (25)