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Virginia Tech

Controlling Object Heat Release Rate using Geometrical Features

Abstract

dc:description.abstract

An experimental study was conducted to determine the effect of complex geometries on the burning rate of materials made using additive manufacturing. Controlling heat release rate has applicability in limiting fire hazards as well as for designing fuels for optimal burning rate. The burning rate of a structure is a function of the material properties as well as the airflow through it, which is dictated by the geometry. This burning rate is generally proportional to the porosity for objects in which the flow is limited by the path constriction. The relations between porosity and burning rate are well studied for wood cribs, which are layers of wood sticks. Crib and other objects with various geometric features were constructed of ABS plastic and coal powder using additive manufacturing processes. A cone calorimeter using oxygen calorimetry was used to measure the heat release rate of the crib specimens. Within the flow limited burning regime, the burning rate of an object is proportional to the porosity factor. Porosity factors calculated from a 1-D theoretical burn rate model as well as from two empirical models were found to correlate the heat release rate results for the crib samples. The heat release rate results of the complex geometries generally correlated to the same porosity factor; however, the model was modified to account for differences between regularly shaped cribs and objects with different sized flow areas. Using the empirical models provides good correlation for the crib burning data and gives a clearer delineation between the flow-limited and surface area controlled regimes.

Degree

thesis:*
Name thesis:degree_name
Master of Science
Level thesis:degree_level
masters
Discipline thesis:degree_discipline
Mechanical Engineering
Department dc:contributor.department
Mechanical Engineering
Grantor dc:publisher
Virginia Tech
Year dc:date.issued
2017

Author and committee

dc:creator, dc:contributor.*
Author dc:creator
  • Kraft, Stefan Marc
Chairs dc:contributor.committeechair
  • Lattimer, Brian Y.
  • Williams, Christopher B.
Committee member dc:contributor.committeemember
  • Diller, Thomas E.

Subjects

dc:subject × 5

Rights

dc:rights
Statement dc:rights
  • In Copyright
Language dc:language.iso
en

Identifiers

dc:identifier.*
Dc Identifier Other
vt_gsexam:11447
OAI identifier oai:identifier
oai:vtechworks.lib.vt.edu:10919/77963

Chain of custody

source
Harvested from
Virginia Tech
Base URL
vtechworks.lib.vt.edu/oai/request
Last updated
2026-07-22
Source record
OAI-PMH GetRecord
citation

Kraft, Stefan Marc. Controlling Object Heat Release Rate using Geometrical Features. masters thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/77963