ntvНаучно-технический вестник информационных технологий, механики и оптикиScientific and Technical Journal of Information Technologies, Mechanics and Optics2226-14942500-0373Университет ИТМО10.17586/2226-1494-2022-22-4-804-811ntv-226Research ArticleМАТЕМАТИЧЕСКОЕ И КОМПЬЮТЕРНОЕ МОДЕЛИРОВАНИЕMODELING AND SIMULATIONЧисленное исследование прямой, винтовой и спиральной капиллярной трубок для хладагента CO2 (на англ. яз.)Numerical study on the straight, helical and spiral capillary tube for the CO2 refrigeranthttps://orcid.org/0000-0002-8043-8883ДжадхавП.JadhavP.

Джадхав Правин — PhD, доцент

sc 57197261154

Сатара, 415001

Pravin Jadhav — PhD (Mech. Eng.), Assistant Professor

sc 57197261154

Satara, 415001

pravin.jadhav@kbpcoes.edu.inhttps://orcid.org/0000-0003-4385-1326СахуА. К.SahuA. K.

Саху Анджан Кумар — PhD, профессор

sc 57201214117

Раягада, Одиша, 765017

Anjan Kumar Sahu — PhD (Mech. Eng.), Professor

sc 57201214117

Rayagada, Odisha, 765017

anjansahu111@gmail.comhttps://orcid.org/0000-0002-8392-8095БаллалС.BallalS.

Баллал Сунита — магистр математики, заведующий кафедрой

Сатара, 415001

Sunita Ballal — M.Sc (Mathematics), Head of Department

Satara, 415001

Sunita.ballal@kbpcoes.edu.inИнженерный колледж Карамвир Бхаурао ПатилИндияKaramveer Bhaurao Patil College of EngineeringIndiaИнститут технологии и науки МаджхигарианиИндияMajhighariani Institute of Technology and ScienceIndia202215122024224804811Copyright © Джадхав П., Саху А., Баллал С., 20242024Джадхав П., Саху А., Баллал С.Jadhav P., Sahu A., Ballal S.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://ntv.elpub.ru/jour/article/view/226

Выполнено численное исследование прямых, спиральных и винтовых капиллярных трубок с хладагентом CO2 и проведено сравнение их характеристик. Численные модели разработаны на основе фундаментальных принципов сохранения массы, импульса и энергии. Решены обыкновенные дифференциальные уравнения во внешнем контуре от входа до выхода капиллярной трубки. Проведены расчеты массового расхода капиллярной трубки и хладагента методом деления отрезка пополам, где масса итеративно рассчитана при заданной длине капилляра или наоборот. Использовано собственное программирование численным методом конечных разностей. Определение характеристик капиллярной трубки выполнено путем расчета ее длины для заданной массы или расчета массы для заданной длины. Выполнено сравнение прямой капиллярной трубки с винтовой (внутренний диаметр 50 мм) и спиральной (шаг 50 мм). Для изменения диаметра трубки, шероховатости поверхности и длины рассчитан процент снижения массового расхода в прямых, винтовых и спиральных капиллярных трубках. В результате сравнения с прямой капиллярной трубкой получено процентное уменьшение массы трубок: для винтовой трубки — 7–9 %, для спиральной — 23–26 %. Для спиральной трубки также получено процентное уменьшение показателей: массы по сравнению с винтовой трубкой — 17–19 %; длины по сравнению с прямой трубкой — 37–43 % и винтовой — 25–32 %.

A numerical study has been carried out for straight, spiral and helical capillary tubes and their performance has been compared with CO2 refrigerant. The numerical models are developed based on the fundamental conservation principles of mass, momentum, and energy. Within this, outer loop, the ordinary differential equations are solved from the inlet to the exit of the capillary tube. The study has been carried out to calculate the mass flow rate by bisection method where the mass is iteratively calculated at the specified capillary length or vice versa. In-house coding programming employs the finite difference approach for numerical solutions. The characterization of the capillary tube has been done by calculating the length for the given mass or by calculating mass for the given length. The comparison of the straight capillary with helical capillary tube (50 mm coil diameter) and spiral capillary tube (50 mm pitch) has been reported. For a change in tube diameter, surface roughness, and length, the percentage reduction in mass flow rate in capillary tubes (straight, helical, and spiral) is calculated. The percentage reduction in mass in a helical capillary tube compared to the straight capillary tube is about 7–9 %. The percentage reduction in mass in a spiral tube compared to the straight capillary tube is nearly 23–26 %. Additionally, the percentage reduction in mass in a spiral tube compared to the helical capillary tube is almost 17–19 %. Additionally, the percentage reduction in length in a spiral tube compared to straight capillary tube ranges from 37 % to 43 %. Similarly, the percentage reduction in length in a spiral tube compared to helical capillary tube is ranging from 25 % to 32 %.

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The authors declare that there are no conflicts of interest present.