Mathematical modelling of applied heat transfer in temperature sensitive packaging systems. Design, development and validation of a heat transfer model using lumped system approach that predicts the performance of cold chain packaging systems under dynamically changing environmental thermal conditions.
Publication date
2013-12-20Supervisor
Roskoss, AlexKeyword
Cold chain packaging systemPredictive model
Lumped system approach
Temperature controlled packaging (TCP)
Predictive model
Institution
University of BradfordDepartment
School of Engineering Design and TechnologyAwarded
2009Metadata
Show full item recordAbstract
Development of temperature controlled packaging (TCP) systems involves a significant lead-time and cost as a result of the large number of tests that are carried out to understand system performance in different internal and external conditions. This MPhil project aims at solving this problem through the development of a transient spreadsheet based model using lumped system approach that predicts the performance of packaging systems under a wide range of internal configurations and dynamically changing environmental thermal conditions. Experimental tests are conducted with the aim of validating the predictive model. Testing includes monitoring system temperature in a wide range of internal configurations and external thermal environments. A good comparison is seen between experimental and model predicted results; increasing the mass of the chilled phase change material (PCM) in a system reduces the damping in product performance thereby reducing the product fluctuations or amplitude of the product performance curve. Results show that the thermal mathematical model predicts duration to failure within an accuracy of +/- 15% for all conditions considered.Type
ThesisQualification name
MPhilCollections
Related items
Showing items related by title, author, creator and subject.
-
Thermo-Economic Modelling of Micro-Cogeneration Systems System Design for Sustainable Power Decentralization by Multi-Physics System Modelling and Micro-Cogeneration Systems Performance Analysis for the UK Domestic Housing Sector(University of BradfordFaculty of Engineering and Informatics, 2015)Micro-cogeneration is one of the technologies promoted as a response to the global call for the reduction of carbon emissions. Due to its recent application in the residential sector, the implications of its usage have not yet been fully explored, while at the same time, the available simulation tools are not designed for conducting research that focuses on the study of this technology. This thesis develops a virtual prototyping environment, using a dynamic multi-physics simulation tool. The model based procedure in its current form focuses on ICE based micro-CHP systems. In the process of developing the models, new approaches on general system, engine, heat exchanger, and dwelling thermal modelling are being introduced to cater for the special nature of the subject. The developed software is a unique modular simulation tool platform linking a number of independent energy generation systems, and presents a new approach in the study and design of the multi node distributed energy system (DES) with the option of further development into a real-time residential energy management system capable of reducing fuel consumption and CO2 emissions in the domestic sector. In the final chapters, the developed software is used to simulate various internal combustion engine based micro-CHP configurations in order to conclude on the system design characteristics, as well as the conditions, necessary to achieve a high technical, economic and environmental performance in the UK residential sector with the purpose of making micro- CHP a viable alternative to the conventional means of heat & power supply.
-
Function Modelling of Complex Multidisciplinary Systems. Development of a System State Flow Diagram Methodology for Function Decomposition of Complex Multidisciplinary Systems(University of BradfordFaculty of Engineering and Informatics, 2015)The complexity of technical systems has increased significantly in order to address evolving customer needs and environmental concerns. From a product development process viewpoint, the pervasive nature of multi-disciplinary systems (i.e. mechanical, electrical, electronic, control, software) has brought some important integration challenges to overcome conventional disciplinary boundaries imposed by discipline specific approaches. This research focuses on functional reasoning, aiming to develop a structured framework based on the System State Flow Diagram (SSFD) for function modelling of complex multidisciplinary systems on a practical and straightforward basis. The framework is developed at two stages. 1) The development of a prototype for the SSFD framework. The proposed SSFD framework are tested and validated through application to selected desktop case studies. 2) Further development and extension of the SSFD framework for the analysis of complex multidisciplinary systems with multiple operation modes and functional requirements. The developed framework is validated on real world case studies collaborated with industrial partners. The main conclusion of this research is that the SSFD framework offers a rigorous and coherent function modelling methodology for the analysis of complex multidisciplinary systems. Further advantages of the SSFD framework is that 1) the effectiveness of the Failure Mode Avoidance (FMA) process can be enhanced by integrating the SSFD framework with relevant tools of the FMA process, and 2) the integration of the SSFD with the SysML systems engineering diagrams is doable, which can promote the take-up of the approach in industry.
-
The Influence of Braking System Component Design Parameters on Pedal Force and Displacement Characteristics. Simulation of a passenger car brake system, focusing on the prediction of brake pedal force and displacement based on the system components and their design characteristics.(University of BradfordSchool of Engineering, Design and Technology, 2015-10-23)This thesis presents an investigation of braking system characteristics, brake system performance and brake system component design parameters that influence brake pedal force / displacement characteristics as ‘felt’ by the driver in a passenger car. It includes detailed studies of individual brake system component design parameters, operation, and the linear and nonlinear characteristics of internal components through experimental study and simulation modelling. The prediction of brake pedal ‘feel’ in brake system simulation has been achieved using the simulation modelling package AMESim. Each individual brake system component was modelled individually before combining them into the whole brake system in order to identify the parameters and the internal components characteristics that influence the brake pedal ‘feel’. The simulation predictions were validated by experimentally measured data and demonstrated the accuracy of simulation modelling. Axisymmetric Finite Element Analysis (using the ABAQUS software) was used to predict the behaviour of nonlinear elastomeric internal components such as the piston seal and the booster reaction disc which was then included in the AMESim simulation model. The seal model FEA highlighted the effects of master cylinder and caliper seal deformation on the brake pedal ‘feel’. The characteristics of the brake booster reaction disc were predicted by the FEA and AMESim simulation modelling and these results highlighted the importance of the nonlinear material characteristics, and their potential contribution to brake pedal ‘feel’ improvement. A full brake system simulation model was designed, prepared, and used to predict brake system performance and to design a system with better brake pedal ‘feel’. Each of the brake system component design parameters was validated to ensure that the braking system performance was accurately predicted. The critical parameter of brake booster air valve spring stiffness was identified to improve the brake ‘pedal ‘feel’. This research has contributed to the advancement of automotive engineering by providing a method for brake system engineers to design a braking system with improved pedal ‘feel’. The simulation model can be used in the future to provide an accurate prediction of brake system performance at the design stage thereby saving time and cost.
