Kvantitativna analiza procesa skrućivanja vode Neumannovom metodom

undergraduate thesis

• Title (english): Quantitative analysis of water freezing process using Neumann's method
• Author: Marta Voda
• Mentor: Antun Galović (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2019-03-01, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Process Energy Engineering

Abstract

U završnom radu je izveden algoritam za skrućivanje kapljevite vode po tzv. kvazistacionarnoj Neumannovoj metodi oko vanjske stijenke cilindra. Proces skrućivanja analiziran je za slučajeve da se kao rashladni medij koristi kapljeviti i paroviti amonijak koji struji kroz cijev različitim (zadanim) brzinama. Ukratko je objašnjena fizika iza procesa skrućivanja te za taj proces skrućivanja su pojašnjeni relevantni načini prijenosa topline. U prvom dijelu rada izvedena je, u bezdimenzijskom obliku, jednadžba vremena skrućivanja zadane debljine leda, te su u dijelu rada izračunati su svi potrebni ulazni parametri za proračun dotične debljine: koeficijenti prijelaza topline i pripadajući bezdimenzijski parametri koji strukturiraju izraz za bezdimenzijsko vrijeme. Nadalje su u radu dijagramski prikazani rezultati proračuna za svih zadanih slučajeva. Potom se daje proračun potrebnih vremena za stvaranje polovice debljine leda izračunatih u prethodnom slučaju, da bi se na kraju rada prikazao za svaki od tih šest slučajeva temperaturni profil voda – sloj leda – stijenka cijevi – rashladni medij.

Abstract (english)

This bachelor’s degree thesis carries out an algorithm for liquid solidification based on the so-called quasistional Neumann's method for the outside wall of a cylinder. The crushing process was analyzed for cases when the liquid and steamy ammonia are flowing through the tube at different (set) speeds. The physics behind the solidification process and heat exchange process are briefly explained. In the first part of the thesis, a non-dimensional algorithm was carried out and all necessary input parameters were calculated for further calculation. (heat transfer coefficient and non-dimensional parameters). Thereafter, a diagrammatic analysis of the formation of a certain thickness of ice is performed for all six cases in the task and the analysis of the time required to create the ice thickness equal to one half of the thickness defined in the first part of the task is described. The final part of the thesis contains a diagrammatic analysis of the water temperature profile - the ice layer - the wall of the pipe - the refrigerant medium

• Keywords: Neumannova metoda; skrućivanje leda; bezdimenzijski oblik; temperaturni profil
• Keywords (english): Neumann's method; ice solidification; non-dimensional shape; the temperature profile
• Language: croatian
• URN:NBN: urn:nbn:hr:235:139339
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-23 00:21:10