k = isoentropic mai magana

Muhimmancin k domin aminci bawul

edita Alessandro Ruzza

by Rentato Pintabona da kuma Panio Colacicco

Girman bawul ɗin aminci waɗanda aka ƙera don fitar da iskar gas ko tururi, bisa ga tarin lspesl “E”, yana buƙatar sanin ma'anar isoentropic k a yanayin fitarwa.

Yin amfani da rashin kulawa na lspesl Collection "E" babi "E.1", game da girman bawuloli masu aminci, na iya haifar da ƙima na iya fitar da bawuloli da fayafai masu fashewa.

Wannan labarin yana ba da wasu jagorori don kimanta ƙimar k don gas na gaske da
yana haskaka kuskure ta hanyar la'akari da k daidai da rabon takamaiman heats Cp/Cv

Babban kuskure na farko da babban abin da za a kauce masa shine amfani da dabarar a cikin Tarin 'E', mai inganci don iskar gas ko tururi, a cikin yanayi inda fitarwa-lokaci biyu na ruwa da gas / tururi yana faruwa. A irin waɗannan lokuta, a zahiri, diamita masu ƙididdigewa ba shakka ba za a yi ƙasa da su ba idan aka kwatanta da ainihin buƙata.

Kuskure na biyu, wanda a lokuta da yawa zai iya haifar da rage girman tsarin tsaro, shine a ba da ma'aunin isoentropic k darajar rabon Cp/Cv. Yayin da batu na farko zai kasance batun jerin labaran da ke gaba, a nan muna so mu ba da wasu alamu masu amfani don ƙididdige ma'anar isoentropic da nunawa, a cikin ƙananan lokuta, girman kuskuren da za a iya yi.

Fitowar isoentropic ta hanyar bututun ƙarfe

Dabarar [1] wanda aka yi amfani da shi a cikin tarin "E", da kuma a cikin wasu Italiyanci [2] da na waje [3] standards, don ƙididdige bawul ɗin aminci waɗanda dole ne su fitar da iskar gas ko tururi, shine na fitowar isoentropic ta cikin bututun ƙarfe a ƙarƙashin yanayin tsalle mai mahimmanci, wanda mafi kyawun iskar gas shine:

ku expansiakan coefficient C yana bayarwa ta:

kasancewa k ma'anar isoentropic expansiakan daidaito:

Sanyi	P1 (bar)	T1 (°C)	q' (kg/h)	q (kg/h)	(q'/q) x 100
methane	12	50	1472	1466	100.4
methane	23	200	2314	2267	102.1
Propane	12	100	2261	2181	103.7
Hexane	12	178	3099	2740	113.1
Hexane	23	220	6519	5111	127.5
Heptane	12	215	3232	2821	114.4

q'= adadin kwarara da aka lissafta tare da k = Cp/Cv (20 °C, 1 atm)
q = adadin kwarara da aka lissafta tare da k = (Cp/Cv) • (Z/Zp)

Ta hanyar gabatar da ƙididdiga na gwaji k na fitar da bawul ɗin aminci, wanda a duk duniya yayi la'akari da ainihin fitowar bawul ɗin, ƙimar aminci na 0.9 da factor factor Z.₁ ga ainihin ruwa, mun isa wurin tsara tarin “E”:

(1) [1]

Alamar isoentropic k za a iya bayyana kamar haka:

[2]

Ga wani manufa gas, don wane P x V / R x T = 1 , an nuna hakan k daidai yake da rabon Cp/Cv tsakanin ƙayyadaddun zafi a matsa lamba da ƙarar.

Ga wani gas na gaske, k ana iya bayyanawa (duba Karin Bayani na B) ta:

[3]

inda Z shine ma'aunin matsawa da aka ayyana ta Z=P x V / R x T kuma Zp shine "matsalar matsawa da aka samo". Lokacin amfani da dabara [3], bisa ga tarin “E”, dole ne a kimanta ƙimar Cp/Cv, Z da Zp a yanayin fitarwa P.₁ da kuma T₁.

An bayyana ma'anar matsi da aka samu Zp a cikin dabara [4] kamar yadda:

Za a iya bayyana ma'anar matsawa Z kamar:

[4]

haka kuma, ana iya bayyana shi kamar haka:

[5]

inda aka tsara ƙimar Z^0, Z^1, Zp^0, Zp^1 a cikin Karin Bayani A matsayin aikin Pr da Tr.

In [4] da kuma [5], Ω shine ma'aunin acentric na Pitzer wanda aka ayyana ta:

[10]

Inda Pr^SAT shine rage matsa lamba na tururi wanda yayi daidai da rage ƙimar zafin jiki Tr=T/Tc=0,7. Shafi A yana nuna ƙimar Ω wasu ruwaye. Z e Zp kuma ana iya samunsa kai tsaye daga ma'aunin nazari na jiha.

Misalin lambobi

Juya zuwa misali na lamba, a ɗauka muna buƙatar ƙididdige ƙarfin fitarwa na bawul ɗin aminci a ƙarƙashin yanayi masu zuwa:

Sanyi		n-Butano
Yanayin jiki		tururi mai zafi
Maganin kwayar halitta	M	58,119
Saita matsa lamba	P	19,78 bar
Ƙarfi		10%
Zazzabi mai ruwa	T	400 K
Efflux coefficient		0,9
Diamita na Orifice	Do	100 mm

Ana ba da matsa lamba ta hanyar:

kasancewa na n-Butane: Tc=425,18 K da PC=37,96 bar, muna da:

da kuma amfani da tebur a cikin Karin A, muna da:

Sanin takamaiman ƙarar tururi a yanayin fitarwa (P1, T1) daidai da 0,01634 m^3/kg (0,0009498 m^3/g-mole), za mu iya kuma ƙididdige Z daga:

Idan aka ba da rabon ƙayyadaddun zafi a matsi da ƙararrawa akai-akai, a yanayin fitarwa (P₁, T₁), daidai da 1,36, daga dabara [3] muna da:

147060

Aiwatar da dabara [1], tare da lissafin adadin kwarara

Aiwatar da dabara [1], wanda aka warware don ƙididdige ƙimar ƙimar, muna da ƙimar ƙimar fitarwa na 147.060 kg / h.

174848

Aiwatar da dabara [1], ta amfani da ƙimar Cp/Cv a 1 atm da 20 ° C

Idan da a maimakon haka mun yi amfani da ƙimar Cp/Cv a 1 atm da 20 ° C, da mun samu. k = 1,19 kuma daga dabara [1] yawan fitarwa na 174.848 kg / h.

Da hakan ya kai mu wuce gona da iri fitarwa iya aiki na aminci bawul ta kewaye 19%

WARNING:

Kuskuren da za a iya yi ta hanyar sanya darajar Cp/Cv zuwa k na iya zama mafi girma fiye da na wannan misali.

Sama da 20%

Don ba da ra'ayi, tebur mai zuwa yana nuna ƙimar ɗigon ruwa mai tsayin mm 18 don sauran cikakkun ma'aunin hydrocarbons, wanda aka ƙididdige su a cikin shari'o'i biyu. An yi lissafin tare da ci gaba na musammanped Software.

Sanyi	P1 (bar)	T1 (°C)	q' (kg/h)	q (kg/h)	(q'/q) x 100
methane	12	50	1472	1466	100.4
methane	23	200	2314	2267	102.1
Propane	12	100	2261	2181	103.7
Hexane	12	178	3099	2740	113.1
Hexane	23	220	6519	5111	127.5
Heptane	12	215	3232	2821	114.4

Software ba ya amfani da dabara [4] [5] amma, farawa daga gyara Redlich da Kwong equation of state, yana ƙididdige ƙimar ma'anar isoentropic ta amfani da haɗin gwiwar thermodynamic.

Muhimmancin ma'anar isoentropic k don bawuloli masu aminci

k = isoentropic mai magana

Muhimmancin k domin aminci bawul

edita Alessandro Ruzza

by Rentato Pintabona da kuma Panio Colacicco

Wannan labarin yana ba da wasu jagorori don kimanta ƙimar k don gas na gaske da
yana haskaka kuskure ta hanyar la'akari da k daidai da rabon takamaiman heats Cp/Cv

Fitowar isoentropic ta hanyar bututun ƙarfe

q'= adadin kwarara da aka lissafta tare da k = Cp/Cv (20 °C, 1 atm)
q = adadin kwarara da aka lissafta tare da k = (Cp/Cv) • (Z/Zp)

Misalin lambobi

147060

Aiwatar da dabara [1], wanda aka warware don ƙididdige ƙimar ƙimar, muna da ƙimar ƙimar fitarwa na 147.060 kg / h.

174848

Idan da a maimakon haka mun yi amfani da ƙimar Cp/Cv a 1 atm da 20 ° C, da mun samu. k = 1,19 kuma daga dabara [1] yawan fitarwa na 174.848 kg / h.

Da hakan ya kai mu wuce gona da iri fitarwa iya aiki na aminci bawul ta kewaye 19%

WARNING:

Kuskuren da za a iya yi ta hanyar sanya darajar Cp/Cv zuwa k na iya zama mafi girma fiye da na wannan misali.

Sama da 20%

Karin Bayani A da B
samuwar dabara

Partner

Muhimmancin ma'anar isoentropic k don bawuloli masu aminci

k = isoentropic mai magana

Muhimmancin k domin aminci bawul

edita Alessandro Ruzza

by Rentato Pintabona da kuma Panio Colacicco

Wannan labarin yana ba da wasu jagorori don kimanta ƙimar k don gas na gaske da yana haskaka kuskure ta hanyar la'akari da k daidai da rabon takamaiman heats Cp/Cv

Fitowar isoentropic ta hanyar bututun ƙarfe

q'= adadin kwarara da aka lissafta tare da k = Cp/Cv (20 °C, 1 atm) q = adadin kwarara da aka lissafta tare da k = (Cp/Cv) • (Z/Zp)

Misalin lambobi

147060

Aiwatar da dabara [1], wanda aka warware don ƙididdige ƙimar ƙimar, muna da ƙimar ƙimar fitarwa na 147.060 kg / h.

174848

Idan da a maimakon haka mun yi amfani da ƙimar Cp/Cv a 1 atm da 20 ° C, da mun samu. k = 1,19 kuma daga dabara [1] yawan fitarwa na 174.848 kg / h.

Da hakan ya kai mu wuce gona da iri fitarwa iya aiki na aminci bawul ta kewaye 19%

WARNING:

Kuskuren da za a iya yi ta hanyar sanya darajar Cp/Cv zuwa k na iya zama mafi girma fiye da na wannan misali.

Sama da 20%

Karin Bayani A da B samuwar dabara

Nagari Gare Ku

Bawul ɗin Tsaro don Aikace-aikacen Hydrogen

Menene bawul ɗin taimako na aminci?

Sharuɗɗa da ma'ana

Partner

Wannan labarin yana ba da wasu jagorori don kimanta ƙimar k don gas na gaske da
yana haskaka kuskure ta hanyar la'akari da k daidai da rabon takamaiman heats Cp/Cv

q'= adadin kwarara da aka lissafta tare da k = Cp/Cv (20 °C, 1 atm)
q = adadin kwarara da aka lissafta tare da k = (Cp/Cv) • (Z/Zp)

Karin Bayani A da B
samuwar dabara