UBC Mechanical Engineering CFD Modeling Group

1. LIME KILNS • Objectives: • Develop a 3-D steady-state computational model to predict the flow and heat transfer in the lime kiln • Use the model to solve problems in kiln operation and design • Model: • Block-structure body-fitted coordinates with domain segmentation, implementation of vortex stretching model, combustion, radiation, and 3-D modeling of the non-Newtonian nature of the lime mud • Benefits: • Maintain maximum operating efficiency for lime kiln and reduce energy consumption TECHNOLOGY TRANSFER License agreement PSL Service agreements Custom agreements Consulting agreements License agreements Government Industry Other Institutions 4 1 . 0 0 . 9 2 0 . 8 0 . 7 0 0 . 6 0 . 5 - 2 0 . 4 0 . 3 - 4 0 . 2 - 4 - 2 0 2 4 0 . 1 0 . 0 5 1 0 1 5 2 0 PULP AND PAPER COMPUTATIONAL FLUID DYNAMICS APPLICATIONS UBC Mechanical Engineering CFD Modeling Group HYDROCYCLONES DIGESTERS • Objectives: • Improve predictions of swirling flows • Develop mathematical models to predict the classification of fibers • Model: • Discretization using block structured curvilinear grids • Modified k- model for highly curved turbulent flows • Particle tracking through explicit time marching based on force balance • End-Users: • Pulp mills requiring high efficiencies for fiber cleaning and fractionation • Objectives: • Model the delignification process occurring within digesters • Calculation of liquid and solid conservation equations for multi-dimensional flow • Model: • Liquid-solid two-phase flow model coupled to the energy and conservation of species equations • Benefits: • Better understanding of process to improve yield and fiber strength Zhengbing Bian Paul Nowak Eric Bibeau Mohammad Shariati Suqin Dong Emil Statie Xioasi Feng David Stropky Mike Georgallis Zhu Zhi Xiao Pingfan He Jerry Yuan Jason Zhang Kegang Zhang Dr. Martha Salcudean Weyerhaeuser Industrial Research Chair Fellow C.S.M.E., F.C.A.A., F.R.S.C. Dr. Ian Gartshore Fellow C.A.S.I RECOVERY BOILERS • Objectives: • Develop modeling tools to improve existing designs and operating procedures, and to lower carry-over and environmental load • Analyze performance of different air systems and liquor firing strategies • Model: • 3-D orthogonal computational method with k- turbulent model, liquor combustion, particle tracking, and wall and gas radiation • Flow equations coupled to the energy and species conservation equations • Predicts gas flows, composition, temperature, and liquor-smelt-char particulate distribution • Benefits: • Powerful modeling tool to optimize recovery boilers, reduce plugging rates, reduce time between water washes, analyze performance of different air systems, improve operating procedures, lower carry-over, and reduce environmental load FUNDING - NSERC - FRBC - B.C. Science Council - Weyerhaeuser - CANFOR - PSL WOOD KILNS • Objectives: • Determine the air flow and moisture distribution in wood kilns • Optimize kiln operations and improve wood quality • Model: • 3-D curvilinear non-orthogonal computational method with transient mass and heat transfer calculations to model the drying process • End-Users: • Kiln operators and manufactures ) s / m ( y t i c o l e V e g a r R = 0 % e v R = 8 % A Flexible Fiber Rotation BARK BOILERS R = 1 5 % • Objectives: • Develop a comprehensive bark boiler gas flow and combustion model • Optimize the thermal efficiency and emissions of boilers and identify promising and cost-effective design upgrades • Model: • Momentum and conservation equations for mass, energy and gas species concentration using the turbulence k- model are solved simultaneously • Chip combustion includes the evaporation of water, release of volatile gases and gas radiation heat transfer • End-Users: • Bark boiler operators and manufacturers Tube Position FLUID-FIBER INTERACTION HEADBOXES • Objectives: • Investigate experimentally flows in headboxes with a range of fiber concentration • Develop computational-based methods to simulate the complex flows occurring in headboxes • Model: • 3-D curvilinear non-orthogonal computational method with low Reynolds k-  model and with non-isotropic, non-linear versions of the k- model • End-Users: • Headbox manufactures and paper mills • Objectives: • Predict and control fiber fractionation according to wood species • Develop a model of flexible fiber motion that includes wall interaction • Compute trajectories of fibers in complex flows • Model fractionation during screening and in hydrocyclones • Benefits: • Improve supply of uniform fibers and increase quality and consistency of pulp