Rus Articles Journal

Determination of heat conductivity of briquettes of

Priskorennya naukovo - tekhn_chny to progress pov`yazano z povny zabezpechennyam consumer kra§n in palivo - energetichny resources. In umova §kh to a def_tsit nadzvichayno vazhlivy znachennya a nabuva º pitannya _ntensif_kats ³ ¿ teployenergetichny protses_v at a zv`yazka z transition on b_lsh visok_ rezhimn_ parameter. B_lsh_st suchasny virobnitstv suprovodzhu?tsya teplotekhnolog_chny processes, v_d correct vedennya yaky lie too long produktivn_st ³ yak_st produkts ³ ¿, shcho vipuska?tsya. In a zv`yazka z tsy, and takozh problems stvorennya bezv_dkhodno ¿ the technologist ³ ¿, okhoron of a navkolishnyy seredovishch that energozber_gayucho ¿ pol_tik znachno zb_lshitsya a role viznachennya optimum teplovy parametr_v provedennya tekhnolog_chny operats_y. So, yak_st osvo?nnya briket_v a r_dky chavun of a pov`yazan z obm_ny energ ³ º yu in teplov_y ³ mekhan_chn_y forms, and takozh vlastivost t_l, shcho vikoristovu?tsya in tsy processes. Rozrakhunok optimum teplotekhn_chny pokaznik_v to permit vstanovit nayvig_dn_sh_ umov prot_kannya protses_v in kisnevy the converter ³, and takozh viznachit ways p_dvishchennya §kh efektivnost_.

Sukupn_st _nformats ³ ¿ shchodo peredach_ it is warm in briquettes ³ umova to a teploobm_n on §kh poverkhn_ a warehouse º sutn_st statements zadach_ teploprov_dnost_. The taka _nformats_ya to enter in zagalny viglyad_ in r_vnyannya ³ dopom_zhn_ sp_vv_dnoshennya, yak_ pov`yazuyut m_zh itself zadan_ parameter z viznacheny sizes. Sukupn_st such r_vnyan ³ sp_vv_dnoshen nazivayut matematichny formulyuvannyam zadach_ I matematichnoit Abo modellyu. At matematichny opisann_ teploprov_dnost_ the yak to the suts_lena seredovishche, m_kroskop_chniya mekhan_zm teploprov_dnost_ not rozglyada?tsya, and vs_ mater_at to a briquette predstavlya?tsya characteristics to process vvazhayutsya neperervny funkts_yam of prostorovy coordinates ³ to hour. Protses perenesennya to warmth of zumovleniye nayavn_styu r_znits_ temperatures m_zh rechovinam, shcho enter in reakts_yu. Temperaturny camp of a t_l of Abo to system t_l harakterizu?tsya the temperaturny field, p_d Yakim reason ³ º tsya sukupn_st mitt?vy znachen temperatures in us_kh points to a scope, shcho rozglyada?tsya. In zagalny viglyad_ r_vnyannya the temperature field ma º viglyad: t= (x, y, z?) t - temperature; x, y, z - coordinate a tochok;? - hour. To the temperatuyena field naziva?tsya to the nestats_onayena. Geometrichne m_sets a tochok to a t_l (briquette), shcho ma º in Donas the moment to hour an odnakova T temperature, nazivayut I _zoterm_chnoit poverkhneyu. Rozd_lennya such poverkhon ploshchina yes º sukupn_st _zoterm (fig. 1). Nayb_lsh r_zko temperature zm_nyu?tsya in a napryamka normal_ n to _zoterm_chno ¿ poverkhn_. Boundary v_dnoshennya? lim? (n? 0) (? T/? n)?????? T/? n=qradT? naziva?tsya hail ³ º nty to temperature. Qie a vector, shcho the directions on normal_ to _zoterm_chno ¿ poverkhn_ aside zrostannya to temperature. Zagalna k_lk_st to warmth, shcho pereda?tsya in protses_ to a teploobm_n through a _zoterm_chna poverkhnyu F ploshchina z captivity to hour?, poznachimo Q?. K_lk_st to warmth, shcho pereda?tsya through poverkhnyu to a briquette in odinitsyu to hour, naziva?tsya a teplovy stream of Q. Poverkhneva shch_ln_st thermal to a stream (to a teplova navantazhennya) q - the heatviy pot_k through odinitsyu poverkhn_. K_lk_st to warmth, heatviy pot_k ³ yoga shch_ln_st pov`yazan_ m_zh sp_vv_dnoshennyam: Q?=? _ 0^??? _F^0?? qdFd?;? Q=? _ F^0? qdF. _ntensivn_st peredach_ to warmth harakterizu?tsya I poverkhnevoit shch_ln_styu thermal to q stream, tobto k_lk_st to warmth, shcho pereda?tsya in odinitsyu to hour through one odinitsyu ploshch_ _zoterm_chno ¿ poverkhn_. Zv`yazok m_zh hail ³ º nty to temperature ³ vector shch_lnost_ thermal to q stream vstanovlyu?tsya v_dpov_dno g_potez_ Trucks’ º sp_vv_dnoshennyam: q = -? grad T. Nev_d’ ?mniya koyef_ts ³ º nt proports_ynost_?, shcho naziva?tsya koyef_ts ³ º nty teploprov_dnost ³, lie too long v_d to a mater_al of a t_l, the yogi to structure ³ to temperature that viznacha?tsya experimentally. Osoblivost_ concrete to process, and nagr_vannya briket_v r_dky chavun z §kh podalshy rozplavlennyam, vstanovlyu?tsya umovam odnoznachnost ³, yak_ skladayutsya _z geometrical, f_zichny, chasovy (Abo pochatkovy) ³ boundary minds. In pershy dvokh m_styatsya v_domost_ about a form ³ rozm_r (briquette) ³ d_yuchy in the yogi about’ ?m_ dzheret a t_l to warmth. Pochatkov_ ³ granichn_ umov about’ ?dnuyutsya I zagalnoit a nazva - krayov_ umov. A stench vkazuyut on osoblivost_ prot_kannya to process in chas_. Granichn_ umov at yaky are set temperature of a seredovishch, shcho an omiva º t_lo by tzh ³ koyef_ts ³ º nty teplov_ddach_? m_zh poverkhneyu t_la ³ navkolishn_m seredovishchy.

In v_dpov_dnost_ z Newton`s law - R_khmana shch_ln_st thermal to a stream, shcho pereda?tsya poverkhn_ to a t_l (briket_v) navkolishn_m seredovishchy (chavuny), q=? (tst - tzh).

Transfer to warmth v_d one teplonos_ya (chavun) to firmly ¿ st_nka nazivayut a heat transfer. Osoblivost_ prot_kannya to process on poverkhn_ a firm t_l at teploperedach_ viznacha?tsya granichny umova tretyy to a sort, yak_ are characterized by temperatures r_din z obokh stor_n to a t_l, and takozh v_dpov_dny koyef_ts ³ º nta teplov_ddach_. Protses teploperedach_ through an odnor_dna to a plask a st_nka a tovshchina? zobrazheniye in fig. 1. Zadan_ koyef_ts ³ º nt teploprov_dnost_ st_nka?, tzh1 r_dina temperature ³ tzh2, koyef_ts ³ º nt teplov_ddach_? 1 ³? 2. Neobkh_dno of a viznachita the heatviy pot_k v_d it is hot ¿ r_din to a st_nka ³ to temperature on poverkhn_ tst1 st_nka ³ tst2.

Shch_ln_st thermal to a stream v_d it is hot ¿ r_din to a st_nka viznacha?tsya for r_vnyannyam:), q=? (tzh1 - tst1).