Category: Biophd

OpenFOAM: COARSER MESH AND ADJUST TIME STEP

OpenFOAM version: 9 Case: clamp_09 Points of note: new coarser mesh, adjust time step implemented, 60 minute simulation. NEW MESHES There is a need for more speed in this simulation. It is currently moving at about 0.1 seconds per second. So a 3 day simulation would take 30 days. To achieve this increase in speed,…
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CONVECTIVE HEAT TRANSFER IN SUGAR BEET STORES

Cover image: a sugar beet clamp captured with a drone mounted thermal camera. Skip to Coding convective heat transfer coefficient as a scalar field. BACKGROUND Convective heat transfer is the process by which heat is transfer from one region to another through the movement of a fluid. It results when there is a temperature difference…
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OpenFOAM: STEADY STATE AIR FLOW THROUGH A SUGAR BEET CLAMP. UPDATE

THIS POST IS AN UPDATE ON A PREVIOUS POST IN WHICH THE WRONG KINEMATIC VISCOSITY WAS APPLIED IN THE SIMULATION. In 2003, Lope G. Tabil and three co-authors decided that they would make my 2021 life much much easier by publishing the paper Airflow Resistance of Sugarbeet. This paper reports some very useful values for…
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OpenFOAM: MODELLING A POROUS MEMBRANE

UNDER CONSTRUCTION 2022-03-03: require experimental data for the permeability of the cover material TopTex. OpenFOAM version: 9 CASE: clamp_06, case_06_empty_clamp Solver: clampPimpleFoam-2 This post builds on two previous posts in which two heat equations were added to the pimpleFoam solver: one for the fluid phase, and one for the solid phase. That said, this post…
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OpenFOAM: pimpleFoam w HEAT TRANSFER -2

Case: clamp_05 Solver: clampPimpleFoam-1 -> clampPimpleFoam-2 This post is the second of two that are a record of how to modify the pimpleFoam solver of OpenFOAM to include heat transfer when there is: a porous region, two phases in this porous region (gas and solid), and a heat source within the solid phase. In the…
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KAPPA

The ‘Thesis’, if you will. The grand description and summary of the doctoral project. This is the template that I will be using, based of discussion with my supervisors, and from looking at the works of some of my recently graduated peers. It is a meta/ broad summary of the project, addressing the general themes…
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SUGAR BEET SURFACE AREA

This post discusses the estimation of the surface area of sugar beet. For now, this is largely guess work – no empirical data to confirm the modelling results has yet been sourced. It seems likely that some experiment data exists (Stefan Paulus at Ifz, I’m looking at you), but it hasn’t been asked for yet.…
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OpenFOAM: pimpleFoam w HEAT TRANSFER -1

Case: clamp_04 Solver: pimpleFoam -> clampPimpleFoam This post is the first of two that a record of how to modify the pimpleFoam solver of OpenFOAM to include heat transfer when there is: a porous region, two phases (gas and solid = porous region), and a heat source within the solid region. In this post, a…
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OpenFOAM – FIFTH ATTEMPT. AIR FLOW THROUGH A SUGAR BEET CLAMP w TRANSIENT SOLVER

A long time ago (2021-02-17), I wrote that I had a feeling there was something wrong with my CFD model of a sugar beet clamp – the rates of air flow seemed a bit low when compared to a few roughly similar cases. It turns out, there was something wrong with it. The viscosity of…
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OpenFOAM – FIFTH ATTEMPT. AIR FLOW THROUGH A VENTILATED SUGAR BEET CLAMP

It’s a very idealised version of a clamp, but it feels pretty OK. The clamp is 8m wide, 2.4m high, and the cross section is 3m broad. The ventilation pipe is 20cm in diameter, and 5.5m long, from x = 0. There are 12 holes in the pipe, each 6cm in diameter and centered at…
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