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Capítulo 12 ESCOAMENTO COMPRESSÍVEL Neste capítulo a Mecânica dos Fluidos funde-se com a Termodinâmica, devido à importância que os fenômenos térmicos adquirem. Por causa disso, a primeira parte do capítulo destina-se a uma compatibilização da nomenclatura e à introdução de conceitos que não haviam sido utilizados até este momento por estarem ligados aos efeitos térmicos. Nas aplicações é mais fácil trabalhar com energias por unidade de massa e não por unidade de peso, fazendo-se as devidas transformações. Esse assunto é extremamente vasto e complexo e o leitor que desejar um maior aprofundamento de seus conhecimentos deverá consultar livros dedicados apenas a ele. O objetivo deste capítulo consiste em alertar o leitor sobre as complicações advindas da variação da massa específica ao longo do escoamento e chamar a atenção para os fenômenos provocados por essa característica. Destacam-se ainda as mudanças de comportamento no escoamento supersônico, a existência de uma vazão em massa máxima nos condutos e o aparecimento da onda de choque. Todos esses fenômenos, abordados dentro de hipóteses simplificadoras, poderão orientar o leitor quando estiver lidando com algum problema prático sobre o assunto. Exercício 12.1 ( ) ( ) ( ) 3 5 2 2 2 p v p v pp m kg226,5 27395260 105 RT p )e kJ627J688.62610956,9218TmcH)d kJ450J888.44910956,6618TmcI)c K.kg J6,661 393,1 6,921 k c c)b K.kg J260 393,1 1393,16,921 k 1kcR 1k kRc)a =+× ×==ρ ==−××=Δ=Δ ==−××=Δ=Δ === =−×=−=→−= Exercício 12.2 ( ) MJ21154,1UkTmcH)d MJ151020460717568,47TmcU kg568,47 293287 2102 RT Vp m)c C460K733 2 5293T T T p p mRTVp mRTVp )b K.kg J717 14,1 287 1k Rc)a K.kg J287 29 315.8R p 6 v 6 1 11 o 2 1 2 1 2 11 22 v =×=Δ=Δ=Δ =×−××=Δ=Δ =× ××== ==×=⇒=→ ⎭⎬ ⎫ = = =−=−= == − Exercício 12.3 ( ) ( ) kg kJ3,93 s m275.93201505,717Tcu K.s m5,717 14,1 287 1k Rc K.s m287 29 315.8 M RR)b C150K423 4,0 27320 4,0 T T4,0 T T )abs(kPa371 4,0 103p 4,0 p pV4,0V V V p p )a 2 2 v 2 2 v 2 2 mol o 4,01k 1 2 1k 2 1 4,12k 1 212 k 1 2 2 1 ==−×=Δ=Δ =−=−= === ==+==→= ==→=→=→⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛= − − ( ) kg kJ6,130 000.1 1201505,004.1h K.kg kJ5,004.1 14,1 2874,1 1k kRc Tch)c p p =×−×=Δ =− ×=−= Δ=Δ Exercício 12.4 K.kg J562 500 500ln3,461 573 423ln872.1 p p lnR T T lncs 1 2 1 2 p −=×−×=−=Δ Exercício 12.5 29,0 342 100 c v s m3422932864,1kRTc s m100 6,3 360v ===Μ =××== == Exercício 12.6 kPa9,5)abs(kPa1,94 6,0 2 14,11 120 2 1k1 p p 2 1k1 p p 14,1 4,1 21k k 2 0 1k k 20 −== ⎟⎠ ⎞⎜⎝ ⎛ ×−+ = ⎟⎠ ⎞⎜⎝ ⎛ Μ−+ = ⎟⎠ ⎞⎜⎝ ⎛ Μ−+= −− − s m2093,3012874,16,0kRTv m kg088,1 3,301287 101,94 RT p C3,28K3,301 6,0 2 14,11 323 2 1k1 T T 3 3 o 22 0 =×××=Μ= =× ×==ρ ===−+ = Μ−+ = Exercício 12.7 ( ) %45,0100 3,67 6,673,67êrro 6,6702,0000.136 19,1 2v m kg19,1 293287 10100 RT p h2 hg2 ppg2v pp g2 v ívelIncompress s m3,672932874,1196,0kRTMv 196,01 100 72,102 14,1 2M 1 p p 1k 2MM k 1k1 p p )abs(kPa72,10210072,2p kPa72,2Pa272002,0000.136hp 1 3 3 Hg Hg 121 21 2 1 4,1 14,1 k 1k 01k k 20 0 Hg0 abs =×−= =××= =× ×==ρ γρ=γ γ=−γ=→γ=γ+→ =××== = ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ −⎟⎠ ⎞⎜⎝ ⎛ −= ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ −⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ −=⇒⎟⎠ ⎞⎜⎝ ⎛ −+= =+= ==×=γ= − − − Exercício 12.8 mm970m97,011 293287 400 4,12 14,1 000.136 10100h 11 RT v k2 1kph1 p h 1RT 1k k2v 14,1 4,1 23 1k k 2 m k 1k m2 == ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ −⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ +××× −×= ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ −⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ +−γ=⇒⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ −⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ γ+−= − − − %8,27100 970 970700 mm700m7,0 000.136 120.95 g pp h Pa120.95 2 400189,1 2 vpp Hg 0 22 0 =×−=ε ===ρ −= =×=ρ=− Exercício 12.9 )abs(Pa102,35,0000.13610hpp)a 45Hg12 ×=×−=γ−= [ ] [ ][ ] [ ] ( ) %113100 47,0 1111 Q Q 1 Q QQ êrro Q Q)c s kg518,0 5,01 32,012 293287 1047,095,0 A A 1 p p 12 A RT pCQ)b 47,0 32,0132,05,01 5,0132,015,332,0 5,0 50 25 A A e32,0 10 102,3 p p p p 1 p p A A 1 A A 1 p p 1 1k k p p m invm m incmmm incm 2 5 2 1 2 1 2 2 1 Dm 429,12 2286,0 714,0 1 2 5 4 1 2 1 2k 2 1 2 2 1 2 2 1 2k 1k 1 2 k 1 1 2 =×⎟⎠ ⎞⎜⎝ ⎛ −=φ−=−= −=⇒φ= =− −× ×××= ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛− ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ − φ= =−××− −×−×=φ ===×= ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ − ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛− ⎥⎥⎦ ⎤ ⎢⎢⎣ ⎡ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛− ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛−− ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛=φ − Exercício 12.10 ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ − ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛− ⎥⎥⎦ ⎤ ⎢⎢⎣ ⎡ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛− ⎥⎥ ⎥ ⎦ ⎤ ⎢⎢ ⎢ ⎣ ⎡ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛−− ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛=φ − 1 2k 2 1 2 2 1 2 2 1 2k 1k 1 2 k 1 1 2 p p 1 p p A A 1 A A 1 p p 1 1k k p p kPa149101,5000.10200hpp 3Hg12 =××−=γ−= − ( ) ( ) ( ) s kg151,1 444,01 745,012 4 1,0 3662077 10200844,095,0Q A A 1 p p 12 A RT pCQ K.kg J2077200.5 665,1 1665,1c k 1kR 1k kRc 844,0 745,01745,0444,01 444,01745,01 1665,1 665,1 745,0 444,0 15 10 D D A A ;745,0 200 149 p p 2 23 m 2 1 2 1 2 2 1 Dm pp 665,1 2 2 2665,1 1665,1 665,1 1 22 1 2 1 2 1 2 =− −×××π×× ×××= ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛− ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ − φ= =×−=−=⇒−= = −×⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ×− −×⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ −×− ×=φ =⎟⎠ ⎞⎜⎝ ⎛=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛=== − Exercício 12.11 ( ) ( ) ( ) ( ) %4,5100 1310 12391310êrro)c s m1310 5,1 15,1 405,12 111015,1 0651.0 2v p pp k2 11pp2v)b s m12391015,1 0651,0 2v m kg0651,0 5504189 105,1 K.s m4189532.14 405,1 1405,1c k 1kR RT p pp2v)a 5 c 0 c0 c0 0 c 5 c 3 5 0 2 2 p 0 0 0 c0c =×−= =⎟⎠ ⎞⎜⎝ ⎛ − ×+××−×= −+−ρ= =×−= =× ×=ρ =×−=−=→=ρ −ρ= Exercício 12.12 s10 2,1477,591 440.7 vv st)c m440.7502,147800.14s s50 296 800.14 c Rt 5,0 296 2,147 c v s m2,147 6,3 530v 2 296 7,591 c v s m7,591 6,3 130.2v s m2962182874,1kRTc)b 21 1 2 22 1 11 =+=+ Δ= =×−=Δ === ===Μ⇒== ===Μ⇒== =××== Exercício 12.13 s m8162952574,137,2kRTMv 37,2 25sen 1M M 1 2 sen o =×××== ==→=α Exercício 12.14 3* * * 133,1 33,1 5 1k k 0*1k k * 0 ** 0*2 * 0 m kg338,0 346462 036.54 RT p )abs(kPa54)abs(Pa036.54 2 133,11 10 2 1k1 p p 2 1k1 p p s m46134646233,1kRTv K346 2 133,11 403 2 1k1 T T 2 1k1 T T =×==ρ == ⎟⎠ ⎞⎜⎝⎛ −+ = ⎟⎠ ⎞⎜⎝ ⎛ −+ =→⎟⎠ ⎞⎜⎝ ⎛ −+= =××== =−+ =−+ =→Μ−+= −− − Exercício 12.15 1.Tab1Ms →= K5,4775738333,0T8333,0 T T )abs(MPa5283,015283,0p5283,0 p p s 0 s s 0 s =×=→= =×=→= s kg338,0102438856,3Q s m4385,4772874,11kRTMv AvQ m kg856,3 5,477287 105283,0 RT p 4 m sss sssm 3 6 s s s =×××= =×××== ρ= =× ×==ρ − Exercício 12.16 2 1* 1 5 0 1 5 1atmHg1 cm1,2015340,1A340,1 A A 8434,0 102 680.168 p p )abs(Pa680.168505,0000.13610pphp =×=⇒=→=×= =×+=⇒=γ− Exercício 12.17 a) T0 = 373 K = 100 oC bloqueadoestánão833,0 102,1 10 p p )b 5 5 0 s →= × = 1.Tab8333,0 p p 0 s →= s kg183,010196984,0AvQ s m1963542874,152,0kRTMv m kg984,0 354287 10 RT p 3 sssm sss 3 5 s s s =××=ρ= =×××== =×==ρ − c) A mesma 1.Tab3,0M)d →= 23m 5 cm6,151056,1 073,1115 193,0 v Q A s m1153662874,13,0kRTMv 073,1 366287 10127,1 RT p =×=×=ρ= =×××== =× ×==ρ − K3543739487,0T9487,0 T T 52,0M s 0 s s =×=→= = )abs(Pa10127,1102,19395,0p9395,0 p p K3663739823,0T9823,0 T T 55 0 0 ×=××=→= =×=→= e) Ms=1 1.Tab→ ⎪⎪⎩ ⎪⎪⎨ ⎧ =×=→= ×==→= K3113738333,0T8333,0 T T )abs(Pa10893,1 5283,0 10p5283,0 p p s 0 s 5 5 0 0 s s kg396,0105,35312,1AvQ s ,m5,3533112874,11kRTMv m kg12,1 311287 10 RT p 3 sssm sss 3 5 s s s =××=ρ= =×××== =×==ρ − Exercício 12.18 ( ) mm64m064,0 000.136 1029564,01h 9564,0 p p erpolandoint38,2 1026,1 103 A A p p p 1 hphp)e m1026,1 59,1 102 59,1 A A)d s m7,1367,2902874,14,0kRTv 59,1 A A 4,0 969,0 300 7,290 T T )c )abs(Pa102p)b )abs(Pa102pp K300TT)a 5 0 A 3 3 * A Hg 0 0 A AHg0 23 3 B* 2BB * B B 0 2 5 A2M 5 2M0 10 ==××−= ⎩⎨ ⎧ =→→=× ×= γ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ − =⇒=γ− ×=×== =×××=Μ= ⎪⎩ ⎪⎨ ⎧ = =Μ →== ×= ×== == − − −− Exercício 12.19 Fixando o sistema de referência no conduto, isto é, no avião: v1 = 180 m/s →→=== =××== 1.Tab55,0 5,327 180 c v M s m5,3272672874,1kRTc 1 1 1 1 1.Tab8,0M 2 →= s m2542512874,18,0kRTMv 222 =×××== Exercício 12.20 s m1,933452874,125,0kRTv )abs(MPa55,0575,0957,0p957,0 p p K345349988,0T988,0 T T 25,0 39,2009,137,2 A A A A A A 009,1 A A )abs(MPa575,0 5913,0 34,0p5913,0 p p K349 8606,0 300T8606,0 T T 9,0 3002874,1 312 kRT v 222 2 0 2 2 0 2 2 * 1 1 2 * 2 * 1 0 0 1 0 0 1 1 1 1 =×××=Μ= ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ =×=→= =×=→= =Μ →=×=×= ⎪⎪ ⎪ ⎩ ⎪⎪ ⎪ ⎨ ⎧ = ==→= ==→= →=××==Μ Exercício 12.21 →== 2 10 20 A A * e rpm49260 22 103 R2 v n s m1032932874,13,0kRTMv ' e'' e ' e =××π×=π=→=××== rpm360460 22 755 R2 v n s m7552932874,12,2kRTMv '' e'''' e '' e =××π×=π=→=××== K283 9449,0 267T9449,0 T T )abs(kPa128 8201,0 100p8201,0 p p 0 0 1 0 0 1 ==→= ==→= K2518865,0283T8865,0 T T )abs(kPa80656,0128p656,0 p p 2 0 2 2 0 2 =×=→= =×=→= 2,2M 3,0M '' e ' e = = Exercício 12.22 22 ss m s 3 5 s s s sss s 0 s s 6 5 0 s 2 G G 22 GG m G GGG 3 5 G G G G 0 G 56 G 0 G G cm413m0413,0 794037,1 34 v Q A m kg037,1 336287 10 RT p )d s m7943362874,116,2kRTv K3366505173,0T5173,0 T T 16,2 1,0 10 10 p p )c m165,010147,24 A4 Dm10147,2 467394,3 34 v Q A s m4675422874,11kRTv)b m kg394,3 542287 1028,5 RT p K5426508333,0T8333,0 T T )abs(Pa1028,5105283,0p5283,0 p p 1)a ==×=ρ= =×==ρ =×××=Μ= ⎪⎩ ⎪⎨ ⎧ =×=→= =Μ == =π ××=π=⇒×=×=ρ= =×××=Μ= =× ×==ρ ⎪⎪⎩ ⎪⎪⎨ ⎧ =×=→= ×=×=→= =Μ −− Exercício 12.23 →= = 1M K310T)a G 0 8333,0 T T 5283,0 p p 0 G 0 G = = .mesmoO)c K2583108333,0T08333T )abs(kPa6,1067,2015283,0p5283,0p)b m kg27,2 310287 107,201 RT p )abs(kPa7,201)abs(kPa695.201p 200.95p5283,0p200.95pp 200.95pp 7,0000.136phpp 0G 0G 3 3 0 0 0 0 00G0 G0 GHgG0 =×== =×== =× ×==ρ == =−→=− += ×+=γ+= Exercício 12.24 2s* 223 ss m s 3 3 s s s xSsss * s s 0 s s 0 s smxS smemsmiiiS cm3,17 999,3 3,69 999,3 A A)c cm3,69m1093,6 864.1348,0 5,4 v Q A m kg348,0 000.1287 10100 RT p )b N838818645,4F s m1864000.12874,194,2kRTv 999,3 A A K000.1730.23665,0T3665,0 T T 94,2 0294,0 400.3 100 p p vQF vQvQvQnApF)a === =×=×=ρ= =× ×==ρ =×−=⇒=×××=Μ= ⎪⎪ ⎪ ⎩ ⎪⎪ ⎪ ⎨ ⎧ = =×=→= =Μ == −= −=+−= − ∑ rrrrr Exercício 12.25 →== 76,1 1,0 176,0 A A * 3 )abs(MPa08,068,01164,0p1164,0 p p 06,2M )abs(MPa622,068,09143,0p9143,0 p p 36,0M '' 3 0 '' 3 '' 3 ' 3 0 ' 3 ' 3 =×=→= = =×=→= = s kg1621,05,31021,5Q s m5,3102402874,11kRTMv m kg21,5 240287 10359,0 RT p )abs(MPa359,068,05283,0p5283,0p K2402888333,0T8333,0T vAQ m GGG 3 6 G G G 0G 0G m =××= =×××== =× ×==ρ =×== =×== ρ= Exercício 12.26 ⎪⎪ ⎪ ⎩ ⎪⎪ ⎪ ⎨ ⎧ =×=⇒= =×=⇒= =×=⇒= →=Μ =×=×=ρ= =×××=Μ= =× ×==ρ ⎪⎪⎩ ⎪⎪⎨ ⎧ =×=⇒= =×=⇒= →=Μ − 2 s* s s 0 s s 0 s s 222 GG m G GGG 3 6 G G G G 0 G G 0 G G cm419251668,1A668,1 A A )abs(MPa0128,01,01278,0p1278,0 p p K1442605556,0T5556,0 T T 2 cm251m1051,2 295815,0 3,6 v Q A s m2952172874,11kRTv m kg815,0 217287 10053,0 RT p K2172608333,0T8333,0 T T )abs(MPa053,01,05283,0p5283,0 p p 1 Exercício 12.27 →== 089,1 293 319 A A * s )abs(MPa516,051,13417,0p3417,0 p p 7358,0 T T 34,1M s 0 s 0 s s =×=→= = = Na realidade, existe também a solução subsônica, entretanto, com essa velocidade de saída, a temperatura seria um valor prático impossível. N342.4110319000.2324,0AvF m kg324,0 544.5287 10516,0 RT p AvF K544.5 2874,134,1 000.2 kRM v TkRTMv 42 s 2 ssS 3 6 s s s s 2 ssS 2 2 2 s 2 s ssss x x =×××=ρ= =× ×==ρ ρ= = ×× ==→= − Exercício 12.28 ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ ===⇒= = =Μ →= =××=××= =⇒=×=×= =××=××== ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ = = = →=Μ ⎪⎪ ⎪⎪ ⎪ ⎩ ⎪⎪ ⎪⎪ ⎪ ⎨ ⎧ = = ===⇒= =Μ →=Μ ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ = = =Μ →= )abs(kPa1,121 8259,0 100 8259,0 p p8259,0 p p 9468,0 T T 53,0 256,1 A A 256,1 176,1 1094,135,1 A A A A A A A A )c A075,1A93,0094,1 176,1 1 A A A A A A )b 46,2 272,0 19298,07209,0 p p p p p p p p Int)a 094,1 A A 7209,0 p p 9108,0 T T 7011,0 458,2p p 32,1 T T )abs(kPa130 9298,0 1,121 9298,0 p p9298,0 p p 7011,0 5,1 176,1 A A 6897,0 T T 5,1 272,0 p p s y0 y0 s 0 s s * y s x * x * y y * x s * y s * x * y* y y x * x * y * x x x0 x0 y0 y0 y x y OC * y y y0 y 0 y y x y x y y0 x0 x0 y0 y x * x x 0 x x x0 x K317 9468,0 300 9468,0 T T)e )abs(kPa130p)d s 0 x0 === = K.kg J8,20 458,2 32,1ln004.1 p p T T lncss)g A6,213A184161,1Q s m1843002874,153,0kRTv m kg161,1 300287 10 RT p AvQ)f 41,1 14,1 k 1k x y x y pxy ssm sss 3 5 s s s sssm =×= ⎟⎠ ⎞⎜⎝ ⎛ =− =××= =×××=Μ= =×==ρ ρ= −− Exercício 12.29 →= 1278,0 p p x0 x →= 2M x →= 58,0M y 437,1213,1 688,1 12 A A A A A A A A * y y x * x * x s * y s =××=××= →= 437,1 A A * y s 688,1 A A 5556,0 T T 2M * x x 0 x x = = = 5,4 p p 687,1 T T 7209,0 p p 5774,0M x y x y 0 0 y x y = = = = 213,1 A A 7962,0 p p 9370,0 T T * y y 0 y 0 y y = = = )abs(Pa1004,1 8650,0 109,0p8650,0 p p 9594,0 T T 46,0M 5 5 0 0 s 0 s s y y ×=×=→= = = m47,0 1036,1 1084,11028,8pph )abs(Pa1028,81084,15,4p5,4p )abs(Pa1084,11044,11278,0p1278,0p php)b K313 9594,0 300 9594,0 T T )abs(kPa144)abs(Pa1044,1 7209,0 1004,1 7209,0 p p)a 5 44 Hg xy 44 xy 45 0x yHgx s 0 5 50 0 x y x = × ×−×=γ −= ×=××== ×=××== =γ= === =×=×== 8650,0 p p x 7962,0 p p x 5283,0 p p x)c y0 s s y0 y yOC x0 G G =→ =→ =→ Exercício 12.30 ⎩⎨ ⎧ =Μ ′′ =Μ′→=×= =Μ→=×= − − 2,2 3,0 2 10 102 A A 76,0756,0 10 1056,7 p p s 3 3 * s s6 5 0 s Sim. Para ser totalmente subsônico Ms ≤ 0,3. Como Ms = 0,76, o escoamento passou para supersônico e posteriormente para subsônico através de uma onda de choque. Exercício 12.31 →=×= − − 4,1 10 104,1 A A )a 3 3 * x c 1850,0 p p 6175,0 T T 76,1M x0 x 0 x x = = = 447,3 p p 502,1 T T 8302,0 p p 6257,0M x y x y x0 y0 y = = = = →= 76,1M x →= 6257,0M y →= × ×= − − 667,1 102,1 102 A A 3 3 * y s ( ) ( ) s kg78,110217122,5AvQ s m1715052874,138,0kRTMv m kg22,5 505287 1056,7 T p )c s m4224836257,032176,12874,1v K4835209286,0T9286,0T K3215206175,0T6175,0T TMTMkRkRTMkRTMvvv)b 3 sssm sss 3 5 ss s s 0y 0x yyxxyyxxyx =×××=ρ= =×××== =× ×=ρ=ρ =×−×××=Δ =×== =×== −=−=−=Δ − Exercício 12.32 Ver o exercício 12.31 Exercício 12.33 23 3y* y* y y 0 y 0 y m102,1 166,1 104,1 166,1 A A166,1 A A 7716,0 p p 9286,0 T T y −− ×=×==→= = = )abs(Pa1035,8 9052,0 1052,7 9052,0 p p9052,0 p p K520 9719,0 505 9719,0 T T)a9719,0 T T 38,0M 5 5 s y0 y0 s s 0 0 s s ×=×==→= ===→= = 24 4 s* y* y s y0 s s m107,33 188,1 1040 188,1 A A188,1 A A 784,0 p p 6,0M −− ×=×==→= = = →== 9324,0 429 400 T T y0 s →= × ×= − − 128,1 107,33 1038 A A 4 4 * y 1 000.136p5283,0p7465,0 )abs(Pa000.136pp php xy 00 Gy yHgG =− =− =γ+ →= 66,0M y ( )absPa109,010013,18876,0p )abs(Pa10013,1p 000.136p5283,0p8876,07465,0 66 0 6 0 00 y x xx ×=××= ×= =−× Exercício 12.34 ⎪⎪ ⎪⎪ ⎪ ⎩ ⎪⎪ ⎪⎪ ⎪ ⎨ ⎧ = = = =Μ →=Μ =×=×=ρ= =×××=Μ= =× ×==ρ ⎪⎪⎩ ⎪⎪⎨ ⎧ =×=⇒= =×=⇒= →=Μ − 783,3 p p 562,1 T T 7947,0 p p 84,1 606,0)b cm924m1024,9 422818,2 110 v Q A s m4224442874,11kRTv m kg818,2 444287 10359 RT p K4445338333,0T8333,0 T T )abs(kPa3596805283,0p5283,0 p p 1)a x y x y x0 y0 x y 222 GG m G GGG 3 3 G G G G 0 G G x0 G G 7465,0 p p 9199,0 T T 66,0M y0 y 0 y y = = = x x y 0y0 0 0 p8876,0p8876,0 p p =→= 2* ys* y s s 2y* y* y y y 2 x* x x x0 x 0 x x cm835.1154.159,1A59,1A59,1 A A 4,0 cm154.1 188,1 1371 188,1 A A188,1 A A 606,0)c cm371.1484,1924A484,1 A A 1537,0 p p 5963,0 T T 84,1 =×=⎪⎩ ⎪⎨ ⎧ =⇒=→=Μ ===⎪⎩ ⎪⎨ ⎧ ⇒=→=Μ ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ =×=⇒= = = →=Μ Exercício 12.35 9325,0 400 373 T T 0 1 == Na segunda situação * 1 A A não muda, mas o escoamento é supersônico. 188,1 A A * 1 = 52,1M x = CouK91274365TTT oxy =−=−=Δ Exercício 12.36 24,1 A A 857,0 429,1 225,1 m kg429,1 400287 10164 RT p )a * x 0 3 3 0 0 0 =⎩⎨ ⎧→==ρ ρ =× ×==ρ 188,1 A A 6,0M * 1 1 = = K274400684,0T684,0T684,0 T T 52,1M 0x 0 x x =×==→= = K365274334,1T334,1T333,1 T T 6941,0M xy x y y =×==→= = s m3663332874,11kRTv K3334008333,0T8333,0 T T 1)c s kg29,410160517519,0AvQ s m5172672874,158,1kRTv m kg519,0 267287 1040 RT p )b )abs(kPa401642423,0p2423,0p2423,0 p p K2674006670,0T6670,0T6670,0 T T 58,1 24,1 A A GGG G 0 G G 4 xxxm xxx 3 3 x x x 0x 0 x 0x 0 x x * x =×××=Μ= =×=⇒= ⎩⎨ ⎧→=Μ =×××=ρ= =×××=Μ= =× ×==ρ ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ =×=×=⇒= =×=×=⇒= =Μ →= − Exercício 12.37 1,0 101 100 p p )a 30 s = × = b) Se a onda de choque está na seção de saída, a montante tem-se a segunda solução isoentrópica, que corresponde à solução do item anterior. 16,2M x = Exercício 12.38 ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ = = =Μ =Μ →== = 666,6 p p 059,2 T T 521,0 42,2 5283,0 p p p p pp x y x y y x x0 y0 x0 G y0G K2,1553005173,0T5173,0T5173,0 T T 16,2M 0s 0 s s =×==→= = K2832,155822,1T822,1T822,1 T T 5525,0M xy x y y =×==→= = s m1853162874,1521,0kRTv K3163339487,0T9487,0 T T 521,0 yyy y 0 y y =×××=Μ= =×=⇒= ⎩⎨ ⎧→=Μ Exercício 12.39 2 máx 1 máx 2 máx 1 máx D L f D Lf D L f D L f D L f D Lf ⎟⎠ ⎞⎜⎝ ⎛+=⎟⎠ ⎞⎜⎝ ⎛→⎟⎠ ⎞⎜⎝ ⎛−⎟⎠ ⎞⎜⎝ ⎛= M2 = 0,9 32,0M1 = L=15m (1) (2) p2 = 105 Pa(abs) T2 = 294 K M2 = 0,9 D = 7,5cm f = 0,02 T0 ? p0 ? 01451,0 D L f )abs(Pa1086,8 129,1 10 129,1 p p129,1 p p K6,284033,1 294 033,1 T T033,1 T T 2 máx 4 5 2* * 2 2* * 2 =⎟⎠ ⎞⎜⎝ ⎛ ×===→= ===→= 0145,401451,0 075,0 1502,0 D L f 1 máx =+×=⎟⎠ ⎞⎜⎝ ⎛ )abs(Pa1031086,8389,3p389,3 p p K7,3346,284176,1T176,1 T T 32,0M 54 1* 1 1* 1 1 ×=××=→= =×=→= = )abs(Pa1022,3 9315,0 103p9315,0 p p K342 9799,0 7,334T9799,0 T T 5 5 0 0 1 0 0 1 ×=×=→= ==→= Exercício 12.40 )abs(MPa011,0259,027,0ppp 176,1 T T )abs(MPa259,00764,0389,3p389,3 p p 32,0 224,4 D L f 224,4 025,0 2,13008,0299,5 D L f D L f D L f 299,5 D L f )abs(MPa0764,0 619,3 27,0 619,3 p p619,3 p p 179,1 T T 3,0 21 * 2 2* 2 2 H máx H máx 1H máx 2H máx H máx 1* * 1 * 1 1 =−=−=Δ ⎪⎪ ⎪ ⎩ ⎪⎪ ⎪ ⎨ ⎧ = =×=⇒= =Μ →=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ =×−=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛−⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ = ===⇒= = →=Μ Exercício 12.41 5,0M1 = 5,0M1 = 1M2 = s m3342772874,11kRTMv 222 =×××== Exercício 12.42 ⎪⎩ ⎪⎨ ⎧ =⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛→=Μ =⎪⎩ ⎪⎨⎧ ⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛→=Μ 3050,0 D Lf 2 5222,0 D Lf 3 2H máx 2 1H máx 1 ( )absMPa166,0 843,0 14,0 843,0 p p843,0 p p 1 0 0 1 1 1 ===→= ( )absMPa124,0 34,1 166,0 34,1 p p34,1 p p 11 0* 0* 0 0 ===→= ( ) K2773338333,0T8333,0T8333,0 T T absMPa065,0124,05283,0p5283,0p5283,0 p p 02 0 2 * 02* 0 2 =×==→= =×==→= 8,1 012,0 1,02172,0 f D2172,0 L 2172,03050,05222,0 D Lf H H máx =×=×= =−=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ Exercício 12.43 3M1 = s m4204392874,11kRTMv *** =×××== 2M2 = s m6852922874,12kRTMv 222 =×××== m17,2 01,0 1,02172,0 f D2172,0L 2172,03050,0522,0 D Lf D Lf D Lf 2,1 2 máx 1 máx2,1 =×== =−=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛−⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛= Exercício 12.44 K245 504,3 p p 1775,1 5,288 1775,1 T T1775,1 T T 31,0 8,4 025,0 602,0 D Lf * 1 1* * 1 1 1 máx = ⎪⎪ ⎪⎪ ⎩ ⎪⎪ ⎪⎪ ⎨ ⎧ = ==⇒= =Μ →=×=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ( ) m22,5 01,0 1,05222,0 f D5222,0L5222,0 D Lf absMPa46,0 2182,0 1,0 2182,0 p p2182,0 p p K439 4286,0 188 4286,0 T T4286,0 T T 1máx 1 máx 1* * 1 1* * 1 =×==→=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ===→= ===→= ( ) 3050,0 D Lf absMPa19,046,04083,0p4083,0p4083,0 p p K2924396667,0T6667,0T6667,0 T T 2 máx * 2* 2 * 2* 2 =⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ =×==→= =×==→= s kg219,0 4 025,0314422,1 4 DvQ s m3142452874,11kRTv m kg422,1 245287 10100 RT p 22 ** máx *** 3 3 * * * =×π××=πρ= =×××=Μ= =× ×==ρ Exercício 12.45 A leitura do termômetro é 600 K, uma vez que a temperatura de estagnação não se altera. →== 2 20 40 A A * 3 →= 2,2M x →= 5471,0M y →== 59,1 5,31 50 A A * y 4 →= 4,0M 4 cm8504 A4 D 44 =π ×=π= 059,1 08,0 502,0309,2 D Lf D Lf D Lf 4 máx 5 máx =×−=−⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ( )absMPa0468,05,009352,0p09352,0p09352,0 p p K3056005081,0T5081,0T5081,0 T T 2,2M x x 0x 0 x 0x 0 x x =×==→= =×==→= = ( )absMPa314,05,06281,0p6281,0p6281,0 p p 5471,0M xy x y 00 0 0 y =×==→= = 23* y* y 3 cm5,31 27,1 40 27,1 A A27,1 A A ===→= ( )absMPa281,0314,08956,0p8956,0p8956,0 p p 4,0M y y 04 0 4 4 =×==→= = ( ) 309,2 D Lf absMPa197,0 59,1 314,0 59,1 p p59,1 p p 4 máx 0* 0* 0 0 yy =⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ ===→= →=⎟⎟⎠ ⎞ ⎜⎜⎝ ⎛ 059,1 D Lf 5 máx s kg68,110501987,1AvQ s m1985802874,141,0kRTv m kg7,1 580287 10283,0 RT p 4 555m 555 3 6 s 5 5 =×××=ρ= =×××=Μ= =× ×==ρ − MPa13,01,023,0p )abs(MPa23,0108,0158,2p38,2 p p 5,0M ef5 5* 5 5 =−= =×=→= =
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