Analysis and Optimisation of Hot Forming Tool Cooling Channels through CFD Simulations and Experimental Validation
2022 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE credits
Student thesis
Abstract [en]
With the development of additive manufacturing, new ways to further improve and optimise cooling channels in press hardening tools are possible, with the prospect of reducing cooling times and achieving uniform cooling across the tool surface. The thesis work was divided into two parts, in the first part called Cooling Channel Design six different cross sections - circular, elliptical, halfmoon, triangular and two droplet shaped - were used in constructed test bodies. The test bodies were analysed through CFD simulations and additively manufactured using SLM technology for experimental validation. The CFD results showed that all cross sections had a higher total heat flux except the droplets which showed similar levels as the conventionally used circular channel. Two test bodies, the elliptical and the circular channel, were tested using an experimental rig. The results showed that a different experimental setup is needed in order to conduct a proper experimental validation. A FE analysis was performed to evaluate if the distance between non-circular cooling channels needs to be altered in order to maintain the same stress levels. The FE results showed that the centerline distance between channels has to be increased with between 10 to 50 mm for all cross sections except the droplet shaped in order to maintain the same stress levels as from using circular channels.
During the second part, called Conformal Cooling Channels a series of cooling channels following the tool surface were designed for a segment of an in use hot forming tool. A total of seven designs were made and evaluated using CFD simulations, the current design with conventionally drilled channels was also simulated for comparison. The results showed that higher heat flux, lower pressure drop and a more evenly spread cooling is possible using conformal cooling channels.
Place, publisher, year, edition, pages
2022. , p. 72
Keywords [en]
Cooling Channels, Heat Transfer, AM, Additive Manufacturing, Conformal Cooling Channels, Conformal, Hot Stamping, Press Hardening, Cooling Channel Design, Optimisation, CFD, Computational Fluid Dynamics, FEM, Finite Element Method, CAD, Computer Aided Design
National Category
Fluid Mechanics
Identifiers
URN: urn:nbn:se:ltu:diva-93609OAI: oai:DiVA.org:ltu-93609DiVA, id: diva2:1703817
External cooperation
Gestamp HardTech
Subject / course
Student thesis, at least 30 credits
Educational program
Mechanical Engineering, master's level
Supervisors
Examiners
Projects
FAMtool2022-10-242022-10-142025-02-09Bibliographically approved