Строительная теплофизика / пример 2
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<g_rgb_ mkeh\by ijb Ψ Θ G ih lZ[e ΙΙ ;h]hke Klj Kljhbl_evgZy l_iehnbabdZ 8N ; d]?d] N ;±nbevljh\ZevgZy [mfZ]Z K mqzlhf W+ & ih
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< b W∞ & ih jbk ΙΙ 8N ; d] d] b ih lZ[e ΙΙ |
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Ih jbk ΙΙ ^ey wlh]h ^bZiZahgZ \eZ`ghklgh_ kj_^g__ agZq_gb_[ηρ f
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& b 8= ; ∞ d] d] ih lZ[e ΙΙ b jbk |
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ΙΙ jZ\_g Θ < Hij_^_ebf baf_g_gb_ Θ |
\h \j_f_gb ih nhjfme_ e_dpby nhjf |
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kimkly kmlhd U |
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>Zggu_ ihegh]h jZkqzlZ k\yaZgu \ lZ[e ΙΙ <ZjbZgl :
<ZjbZgl < Ijh\_^zf ihklhygguc jZkqzl k mqzlhf baf_g_gby l_iehnbabq_kdbo oZjZdl_jbklbd fZl_jbZeZ \ ijhp_kk_ \ukuoZgby HD
>Zggu_ jZkqzlZ d ijbf_jm ΙΙ
<j_fy q |
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Ijb wlhf l_iehnbabq_kdb_ oZjZdl_jbklbdb fZl_jbZeZ ^ey dZ`^h]h gh\h]h jZkqzlgh]h bgl_j\ZeZ [m^_f ijbgbfZlv ih kj_^g_c \eZ`ghklb ]Zah[_lhgZ \ dhgp_ ij_^u^ms_]h jZkqzlgh]h bgl_j\ZeZ JZkqzlgu_ bgl_j\Zeu \j_f_gb ∆Ζ = kml = q
I_j\uc jZkqzlguc bgl_j\Ze
Hij_^_ebf ih jbk ΙΙ ^ey 8 = ; = [ηρ
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Hij_^_ebf ih nhjfme_ ΙΙ |
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Ih jbk ΙΙ >EY Θ < W∞ & hij_^_ebf 8N ; dhlhjZy ih jbk ΙΙ kf ;h]hke Kljhbl_evgZy l_iehnbabdZ klj khhl\_lkl\ ϕ Θ
Jbk ΙΙ RdZeZ hlghkbl_evgh]h ihl_gpbZeZ \eZ`ghklb aZ\bkbfhklv jZ\gh\_kgh]h \eZ]hkh^_j`Zgby nbevljh\Zevghc [mfZ]b BN; hl hlghkbl_evgh]h ihl_gpbZeZ \eZ`ghklb
>Ze__ ih lZ[e ΙΙ 8= ; d] d] Ih wlhfm agZq_gbx 8= ; ∆ ]±hij_^_ey_l l_iehnbabq_kdb_ oZjZdl_jbklbdb ]Zah[_lhgZ ^ey \lhjh]h jZkqzlgh]h bgl_j\ZeZ b l ^ Ijhba\h^bf jZkqzlu ^ey ihke_^mxsbo bgl_j\Zeh\ ^Zggu_ dhlhjh]h aZg_k_gu \ lZ[e ΙΙ
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