Строительная теплофизика / 3

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<b^u i_j_^Zqb l_iehlu

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L_iehijh\h^ghklv

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T = −λ JUDG∂ W

]^_ dhwnnbpb_gl l_iehijh\h^ghklb <l fžK

4 = T )

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DZ`^uc kehc bf__l aZ^Zggmx lhesbgm / b dhwnnbpb_gl l_iehijh\h^ghklb

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4 = W − WQ+ )

∑Q 5

L=

>ey jZkq_lZ l_ieh\h]h ihlhdZ q_j_a fgh]hkehcgmx beb h^ghkehcgmx pbebg^jbq_kdmx kl_gdb _keb lhesbgZ __ ih kjZ\g_gbx k ^bZf_ljhf G g_agZqbl_evgZ fh`gh ihevah\Zlvky nhjfmehc ^ey iehkdhc kl_gdb

Ijb wlhf iehsZ^v ) ih^kqblu\Z_lky )kj = π Gkj O

f_`^m gZjm`ghc b \gmlj_gg_c ih\_joghklyfb _]h kl_gdb

Dhg\_dlb\guc l_iehh[f_g

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4 = α d ) W` − Wkl

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Ijbgy\ ) f ihemqbf ih\_joghklgmx iehlghklv l_ieh\h]h ihlhdZ T <l f

T = α W` − Wkl

Ba mjZ\g_gby fh`gh hij_^_eblv jZaghklv W` Wkl b l_fi_jZlmjm Wkl

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LZdbf h[jZahf l h

α = I 9 µ ρ & S β W` Wkl N O O O

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Ijb\_^_f g_dhlhju_ djbl_jbb ih^h[by ^ey hij_^_e_gby . b bo djZldmx oZjZdl_jbklbdm

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DZdb_ `_ y\e_gby ijhp_kku oZjZdl_jbamxl wlb djbl_jbb"

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±eZfbgZjgh_ ijb 5H! ±lmj[me_glgh_ l_q_gb_

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< h[s_f kemqZ_ djbl_jbZevgZy aZ\bkbfhklv dhg\_dlb\gh]h l_iehh[f_gZ bf__l \b^

1X = I 5H*U 3U

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1X = *U 3U

>ey hij_^_e_gby dhwnnbpb_glZ l_iehhl^Zqb ih mjZ\g_gbx ih^kqblu\Zxlky qbkeh\u_ agZq_gby djbl_jb_\ \oh^ysbo \ ijZ\mx qZklv jZ\_gkl\Z hij_^_ey_l djbl_jbc 1X b ba g_]h±dhwnnbpb_gl l_iehhl^Zqb α

L_iehh[f_g baemq_gb_f

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Jbk Ko_fZ jZkij_^_e_gby emqbklhc wg_j]bb iZ^Zxs_c gZ l_eh

H[hagZqbf q_j_a 4 ±h[s__ dhebq_kl\h emqbklhc wg_j]bb iZ^Zxs_c gZ l_eh Z q_j_a 4$ 45 b 4'±khhl\_lkl\_ggh dhebq_kl\h emqbklhc wg_j]bb ih]ehs_gghc 4$ hljZ`_gghc45 b ijhr_^r_c q_j_a g_]h 4' L _

4 = 4$ + 45 + 4'

JZa^_eb\ h[_ qZklb jZ\_gkl\Z gZ 4 ihemqbf

4 = 4$ = 45 = 4' beb = $ + 5 + ' 4 4 4 4

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Hkgh\gu_ aZdhgu l_ieh\h]h baemq_gbyAZdhg Kl_nZgZ ;hevpfZgZ±mklZgZ\eb\Z_l k\yav baemqZl_evghc kihkh[ghklb Z[khexlgh q_jgh]h l_eZ k l_fi_jZlmjhc 7 .

( = & 7 .

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4ϕ = 4 FRVϕ

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W 7 l _ ? : = ? = I 7

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