title: Modelling heat transfer during chilling and freezing of packaged foods in industrial refrigeration facilities

authors: Hoang, Duy

subjects: Modelling

abstract: Industrial refrigeration equipment companies are continuously looking for ways to optimise the design of chilling and freezing tunnels in order to minimise food quality loss and increase the energy efficiency of the equipment. However, possibilities for dedicated experimental tests of the industrial operations are limited due to a large amount of food product involved while the number of design variables to be considered is high. A cost-effective alternative to experiments is numerical modelling. The main goal of this research was to simulate heat transfer of packaged food products in a chilling and freezing tunnel. Computational fluid dynamics (CFD) models were developed to improve prediction in industrial cheese chilling and chicken freezing. The industrial cheese chilling model was developed based on six blocks of agar that mimic the product arrangement and airflow pattern of a cheese chiller; while the chicken freezing model represents the first case of a CFD freezing model where the geometry was derived empirically via computed tomography scan data. The model predictions were validated by experimental temperature histories generated as part of the study. Once validated, the model was used to investigate the cooling heterogeneity and the effect of different operating conditions on the processing time. In addition to the CFD model, a simple heat transfer simulation based on the one-dimensional finite difference method was developed for industrial users. Thermal property models in the literature were also reviewed to propose the most suitable choice for thermal processing calculations.

text: Modelling heat transfer during chilling and freezing of packaged foods in industrial refrigeration facilities Industrial refrigeration equipment companies are continuously looking for ways to optimise the design of chilling and freezing tunnels in order to minimise food quality loss and increase the energy efficiency of the equipment. However, possibilities for dedicated experimental tests of the industrial operations are limited due to a large amount of food product involved while the number of design variables to be considered is high. A cost-effective alternative to experiments is numerical modelling. The main goal of this research was to simulate heat transfer of packaged food products in a chilling and freezing tunnel. Computational fluid dynamics (CFD) models were developed to improve prediction in industrial cheese chilling and chicken freezing. The industrial cheese chilling model was developed based on six blocks of agar that mimic the product arrangement and airflow pattern of a cheese chiller; while the chicken freezing model represents the first case of a CFD freezing model where the geometry was derived empirically via computed tomography scan data. The model predictions were validated by experimental temperature histories generated as part of the study. Once validated, the model was used to investigate the cooling heterogeneity and the effect of different operating conditions on the processing time. In addition to the CFD model, a simple heat transfer simulation based on the one-dimensional finite difference method was developed for industrial users. Thermal property models in the literature were also reviewed to propose the most suitable choice for thermal processing calculations.

year: 2020

title: Infrastructure new findings for New Zealand

authors: Grimes, Arthur

subjects: economics

abstract: Infrastructure is a crucial input into economic production, and provision of infrastructure is a key avenue through which government may materially raise economic productivity. Recognising the importance of infrastructure investment, the Foundation for Research, Science and Technology granted Motu and its research partners a four-year research grant to examine the impacts that infrastructure investments have on New Zealand’s economic development. The programme has resulted in a range of empirical research studies that examine the impacts of specific and general infrastructure investments in this country. It has also resulted in contributions addressing theoretical and funding aspects related to infrastructure investment.

text: Infrastructure new findings for New Zealand Infrastructure is a crucial input into economic production, and provision of infrastructure is a key avenue through which government may materially raise economic productivity. Recognising the importance of infrastructure investment, the Foundation for Research, Science and Technology granted Motu and its research partners a four-year research grant to examine the impacts that infrastructure investments have on New Zealand’s economic development. The programme has resulted in a range of empirical research studies that examine the impacts of specific and general infrastructure investments in this country. It has also resulted in contributions addressing theoretical and funding aspects related to infrastructure investment.

year: 2010

title: Māori in the Faculty of Arts and Social Sciences: An analysis of the Faculty of Arts and Social Science data records from 1997-2002

authors: Ashwell, Allanah

subjects: Maori students

abstract: The Ministry of Education has compiled annual reports on the participation of Maori in
tertiary education. The 2002 report presented a comprehensive description of Maori
participation across all tertiary institutions within New Zealand in that year. The figures
show that Maori are markedly under-represented in tertiary institutions, particularly
universities.
The barriers encountered by Maori students can either directly or indirectly impact on
Maori participation, retention and success. The more disturbing outcome is that of
withdrawal or dropping out of higher education, is more likely when a Maori student
experiences and has to confront multiple rather than single barriers.
With this in mind, the aim of this study was to examine and identify trends apparent in
data records of Maori students enrolled in courses offered by the Faculty of Arts and
Social Sciences at the University of Waikato between 1997 and 2002 and to make
recommendations to the Faculty about how negative trends might be addressed. Specific
areas for analysis are detailed in the report.

text: Māori in the Faculty of Arts and Social Sciences: An analysis of the Faculty of Arts and Social Science data records from 1997-2002 The Ministry of Education has compiled annual reports on the participation of Maori in
tertiary education. The 2002 report presented a comprehensive description of Maori
participation across all tertiary institutions within New Zealand in that year. The figures
show that Maori are markedly under-represented in tertiary institutions, particularly
universities.
The barriers encountered by Maori students can either directly or indirectly impact on
Maori participation, retention and success. The more disturbing outcome is that of
withdrawal or dropping out of higher education, is more likely when a Maori student
experiences and has to confront multiple rather than single barriers.
With this in mind, the aim of this study was to examine and identify trends apparent in
data records of Maori students enrolled in courses offered by the Faculty of Arts and
Social Sciences at the University of Waikato between 1997 and 2002 and to make
recommendations to the Faculty about how negative trends might be addressed. Specific
areas for analysis are detailed in the report.

year: 2003-06