Evaporation of refrigerant R134a, R404A and R407C with low mass flux in smooth vertical tube

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26110%2F21%3APU141627" target="_blank" >RIV/00216305:26110/21:PU141627 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0017931021009509" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0017931021009509</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijheatmasstransfer.2021.121845" target="_blank" >10.1016/j.ijheatmasstransfer.2021.121845</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Evaporation of refrigerant R134a, R404A and R407C with low mass flux in smooth vertical tube

Popis výsledku v původním jazyce

This experimental study analysis the low mass flux of refrigerant R134a, R404A, and R407C in the smooth vertical evaporator tube with an inner diameter of 32 mm. This downward-flow refrigerant with a mass flux of about 9 kg m −2 s −1 in the parallel/counter flow of heating water shows suppressed heat trans- fer by convective boiling and dominant heat transfer by nucleate boiling. This dominant heat transfer by nucleate boiling is dependent on the superheated wall of evaporator tube. The experimentally obtained Nusselt number correlates 92.2 % for R134a, 92.4 % for R404A, and 83.2 % for R407C with the predicted Nusselt number for mass flux over 10 kg m −2 s −1 . In summary, the untypically low mass flux of refrig- erant about 9 kg m −2 s −1 is comparable with the current state of knowledge for low mass flux over 10 kg m −2 s −1 .

Název v anglickém jazyce

Evaporation of refrigerant R134a, R404A and R407C with low mass flux in smooth vertical tube

Popis výsledku anglicky

This experimental study analysis the low mass flux of refrigerant R134a, R404A, and R407C in the smooth vertical evaporator tube with an inner diameter of 32 mm. This downward-flow refrigerant with a mass flux of about 9 kg m −2 s −1 in the parallel/counter flow of heating water shows suppressed heat trans- fer by convective boiling and dominant heat transfer by nucleate boiling. This dominant heat transfer by nucleate boiling is dependent on the superheated wall of evaporator tube. The experimentally obtained Nusselt number correlates 92.2 % for R134a, 92.4 % for R404A, and 83.2 % for R407C with the predicted Nusselt number for mass flux over 10 kg m −2 s −1 . In summary, the untypically low mass flux of refrig- erant about 9 kg m −2 s −1 is comparable with the current state of knowledge for low mass flux over 10 kg m −2 s −1 .

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20101 - Civil engineering

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

International journal of heat and mass transfer

ISSN

0017-9310

e-ISSN

1879-2189

Svazek periodika

181

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

8

Strana od-do

1-8

Kód UT WoS článku

000709735900001

EID výsledku v databázi Scopus

2-s2.0-85115222915