• A Non-normal-mode Marginal State of Convection in a Porous Box with Insulating End-Walls 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Journal article; Peer reviewed, 2019)
      The 4th order Darcy-Benard eigenvalue problem for the onset of thermal convection in a 3D rectangular porous box is investigated. We start from a recent 2D model for a rectangle with hand-picked boundary conditions defying ...
    • A Non-normal-Mode Marginal State of Convection in a Porous Rectangle 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen; Storesletten, Leiv (Journal article; Peer reviewed, 2019)
      The fourth-order Darcy–Bénard eigenvalue problem for onset of thermal convection in a 2D rectangular porous box is investigated. The conventional type of solution has normal-mode dependency in at least one of the two spatial ...
    • Laterally Penetrative Onset of Convection in a Horizontal Porous Layer 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Peer reviewed; Journal article, 2020)
      The onset of Darcy–Bénard convection in an unlimited horizontal porous layer is studied theoretically. The thermomechanical boundary conditions of Dirichlet or Neumann type at the lower and upper plane are switched from ...
    • A Length Scale Approach to the Highest Standing Water Wave 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Journal article; Peer reviewed, 2021)
      The highest standing surface wave at infinite depth is a classical hydrodynamic problem, illuminated by Taylor’s ex- cellent experiments [Taylor, G. I., Proc. R. Soc. Lond. Ser. A 218, 44 (1953)]. Based on length scale ...
    • Non-normal-Mode Onset of Convection in a Vertical Porous Cylinder 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Peer reviewed; Journal article, 2020)
      This is the first study reporting a full three-dimensional (3D) non-normal-mode onset of convection in a porous medium. In this paper, the onset of thermal convection in a vertical porous cylinder is investigated theoretically. ...
    • Onset of Convection in a Triangular Porous Prism with Robin-Type Thermal Wall Condition 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Journal article; Peer reviewed, 2019)
      This paper investigates a peculiar case of thermal convection in a vertical porous prism with impermeable and partially conducting walls. We facilitate the analysis in the numerical finite-element environment alongside ...
    • Onset of Convection in Two-Dimensional Porous Cavities with Open and Conducting Boundaries 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Journal article; Peer reviewed, 2021)
      The onset of thermal convection in two-dimensional porous cavities heated from below is studied theoretically. An open (constant-pressure) boundary is assumed, with zero perturbation temperature (thermally conducting). The ...
    • Oscillatory Convection Onset in a Porous Rectangle with Non-analytical Corners 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Peer reviewed; Journal article, 2020)
      The analytical theory on Darcy–Bénard convection is dominated by normal-mode approaches, which essentially reduce the spatial order from four to two. This paper goes beyond the normal-mode paradigm of convection onset in ...
    • Oscillatory Non-normal-Mode Onset of Convection in a Porous Rectangle 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Journal article; Peer reviewed, 2019)
      A special case of the fourth-order Darcy–Bénard problem in a two-dimensional (2D) rectangular porous box is investigated. The present eigenfunctions are of non-normal-mode type in the horizontal and vertical directions. ...
    • Peaked sloshing in a wedge container 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Peer reviewed; Journal article, 2021)
      Finite-amplitude free-surface flow in a wedge container is investigated analytically. We study a motionless standing wave of pure potential-flow acceleration with maximal amplitude where its right-angle surface peak falls ...
    • Stagnant peaked free surface released at a sloping beach 

      Tyvand, Peder A.; Nøland, Jonas Kristiansen (Peer reviewed; Journal article, 2021)
      A stagnant free-surface flow is an instantaneous flow field of pure acceleration with zero velocity and a deformed surface. There exists a potential-flow acceleration field. With zero velocity and the acceleration field ...