Computational Fluid Dynamic investigation and optimization of biomass production using vertical stacking units

Dr Lindsay-Marie Armstrong, Prof Gail Taylor

Biomass has become an attractive renewable climate solution which enables potential CO2-negative options in the form of bioenergy carbon capture and storage (BECCS). Whilst capturing CO2 is well-established BECCS is still considered a challenge, due to the volume of biomass that would be required. The IPCC 1.5°C report states that all pathways that limit global warming to 1.5°C or 2.0°C require removing atmospheric CO2 with BECCS playing a primary role. However, this estimates removing ~100 - 1,000 billion tons of CO2 over the 21st century. Furthermore, converting 300 - 700 million hectares of cropland to support biomass production is simply incompatible with increasing food demands whilst increased biomass crop production enhances risk of forest fires.

Growing biomass in vertical production units could reduce the footprint requirements and offer a containment route to minimize fire distribution; however, it has yet to be thoroughly investigated as a option. There are numerous technical and biological challenges that need thorough consideration, including effective distribution of nutrients, both mineral as well as gaseous exchange; impact of light access; localized temperature and localized variation to gaseous species. Coupling computational tools that take into account local species distributions alongside experimental studies would probe these challenges swiftly, which is essential given the ambitious targets.


The aim of this project is to perform a range of computational fluid dynamics investigations into biomass production within a vertical stacking unit.

0-9mths: The computational models will initially investigate the distribution and flow of air within the biomass unit to ensure exposure of required gaseous is met across the unit.

Output – Paper outlining the flow behaviours within different vertical biomass units with a range of flow controls. 

9-18mths: The model will be expanded to introduce the consumption and evolution of localized gaseous species via species transport modelling.

Output – Paper presenting CO2 consumptions and O2 evolution at different locations of a vertical biomass unit.

18-36mths: Investigations will consider the impact of controllable operating conditions on gaseous exchange, e.g., unit temperatures, biomass type; and proximity of the biomass plants. A quantified review of production rates based on the parameters, and subsequent cost of operation would be explored to determine optimal biomass units and operating conditions.

Output - Paper presenting an extensive parametric investigation into the potential of vertical biomass units that are optimized to promote maximise yield over minimized footprint and operating cost.

The project will be validated against vertical biomass production units at UC Davies, where Taylor is predominantly based. 

University of Southampton

The INSPIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted at the School of Engineering, Mechanical Engineering. Specific training will include:

  • Research skills and techniques,
  • Access to MSc level modules on Low Carbon technologies and Biofuels
  • Access to Computational Fluid Dynamics training workshops.
Eligibility & Funding Details: 

Please see for details.

Background Reading: 
  • Donnison,C; Holland, R.A., Hastings, A; Armstrong, L.M.; Eigenbrod, F; Taylor, G.; Bioenergy with Carbon Capture and Storage (BECCS): Finding the win–wins for energy, negative emissions and ecosystem services—size matters; GCB Bioenergy; Volume 12, Issue 8 p. 586-604, 2020
  • Armstrong, L.M.; Luo, K.H.; Gu, S.; Two-dimensional and three-dimensional computational studies of hydrodynamics in the transition from bubbling to circulating fluidised bed; Chem. Eng. J. 160 (1), 239-248
  • Hastings, A.; Tallis, M.I.;  Casella, E.; Matthews, R.A; Henshall, P.A.; Milner,S.; Smith, P.; Taylor, G; The technical potential of Great Britain to produce ligno-cellulosic biomass for bioenergy in current and future climates; GCB Bioenergy Volume 6, Issue 2 p. 108-122, 2013