Changes between Version 21 and Version 22 of palm4u

Timestamp:

Nov 18, 2018 6:52:29 AM (6 years ago)

Author:

maronga

Comment:

--

palm4u

@@ -25 +25 @@
 
 == Reynolds-averaged Navier Stokes (RANS) type turbulence parameterization [=#rans] ==
-
-[[NoteBox(note,The TKE-ε−parameterization will be implemented within the coming months In the meantime a TKE-l-closure has been implemented!)]]
-
 As alternative to the turbulence-resolving LES mode, PALM-4U offers a RANS-type turbulence parameterization. In more detail, a so-called TKE-
 ε−parameterization (Kato and Launder, 1993; Lopez et al., 2005) is implemented, which is based on two prognostic equations for the turbulence kinetic energy (TKE) and its dissipation rate ε.
@@ -38 +35 @@
 
 == Land surface representation [=#lsm] ==
-[[NoteBox(note,The coupling of 3D vegetation to the soil model and energy balance for leaf temperatures is still under development and is expected to be available in May 2018!)]]
-
 For natural and paved surfaces in urban environments, PALM-4U employs PALM's land surface model. The scheme consist of an energy balance solver for all different types of surfaces as well as an multi-layer soil model to account for vertical diffusion of heat and water transport in the soil. For natural vegetated surfaces, the energy balance solver will use the concept of a skin layer that has no heat capacity but considers the insulating effect of plants. In the absence of vegetation, no skin layer approach is used and the surface temperature is taken equal to the outermost soil, pavement, or wall layer.
 
@@ -48 +43 @@
 
 == Indoor climate and building energy demand [=#indoor] ==
-[[NoteBox(note,The indoor model is currently undergoes final editing and will be available within the coming months!)]]
 In order to calculate the interaction of the buildings with the atmosphere, a holistic indoor climate model is available in PALM-4U. This model predicts the indoor temperature and also calculates both the energy demand of each building as well as the waste heat that is released to the atmosphere. The model is integrated as an optional module that is coupled to the wall model by using the temperature of the innermost wall layer of the respective building facades as input parameter. Also, the transmitted radiation by windows is transferred to the indoor model. The indoor temperature is then calculated based on building characteristics (e.g. insulation, air conditioning, and heating). In return, the indoor temperature is transferred to the wall model as boundary condition, while waste heat from heating or air conditioning is fed back into the atmosphere as an additional tendency in the prognostic equation for temperature at the roof top (representing the typical location of chimneys and air conditioning units).
 
@@ -55 +49 @@
 
 == Chemistry [=#chem] ==
-[[NoteBox(note,Parts of the planned chemistry implementation are still under development!)]]
 A fully "online" coupled (Baklanov et al., 2014) chemistry module is implemented into PALM. The chemical species are treated as Eulerian concentration fields that may react with each other, and possibly generate new compounds. For the description of gas-phase chemistry the latest version of Kinetic Preprocessor (KPP 1 ) version 2.3 has been implemented into PALM-4U (see also Damian et al., 2002; Sandu et al., 2003; Sandu and Sander, 2006). It allows to generate Fortran source code directly from a list of chemical rate equations. A further preprocessor (KP4) has been developed that adapts the code to PALM and automatically generates interface routines between the KPP generated modules and PALM. In this way, the chemistry in PALM-4U is fully flexible and easily exchangeable. The PALM chemistry module is implemented in RANS and LES modes. A more complex chemistry module is available for the RANS mode, whereas a strongly simplified chemistry mechanism is available for the LES mode to keep the computational time for chemical transformations and advection of the species at a reasonable level.
 
 == Multi-agent system [=#mas] ==
-[[NoteBox(note,The multi-agent system is currently under development and is expected to be available in May 2018!)]]
 The conventional approach to assess biometeorological aspects in urban areas is an Eulerian approach, i.e., the area-wide evaluation of relevant parameters and indices, and subsequent mapping and zoning of these parameters. In this approach, socio-economic aspects of urban residents, such as resident characteristics like age, skin sensitivity, wealth, or population density and the typical behavior and movement patterns of these residents are usually neglected. In order to account for these additional parameters, a multi-agent system is implemented in PALM-4U that allows a new quality of biometeorological assessment studies. The multi-agent system is a Lagrangian approach in which groups (from hundreds to several thousands) of individual agents (i.e., residents) are released at selected locations of interest in the model domain (see e.g. Bruse, 2007; Chen and Ng, 2011; Gross, 2015, for further reading). Each agent can have individual characteristics (age, clothing, speed, starting points, targets, etc.) so that typical population groups can be statistically represented and released in the model. Each agent is able to move according to a path-finding algorithm that takes into account not only the agent’s characteristics, but also the atmospheric conditions in its surroundings, like sun/shaded area, searching for an optimal compromise between the fastest and most convenient path. The path-finding algorithm will be based on a potential field scheme where the direction of movement is determined from the sum of forces acting upon the agent. The potential itself can be regarded as the result of a force towards the target area and additional forces due to sloped terrain, forbidden areas (buildings), shaded and non-shaded sites, or the occupation of areas by other agents.
 
@@ -65 +57 @@
 
 == Human biometeorology [=#bio] ==
-[[NoteBox(note,The multi-agent system is currently undergoes final editing and is expected to be available in the coming months!)]]
 The evaluation of human thermal and wind comfort/stress as well the exposure to UV radiation is treated in both the classical Eulerian way, but also in the Lagrangian multi-agent system. Standard biometeorological thermal indices like Physiologically Equivalent Temperature (PET), Perceived Temperature (PT), and Universal Thermal Climate Index (UTCI) as well as wind comfort are calculated area-wide directly by the biometeorology module in PALM-4U and provided as output data. The module is based on the existing models RayMan (Matzarakis et al., 2010) and Sky-Helios (Matzarakis and Matuschek, 2011). Moreover, a Lagrangian version is implemented in that sense that the thermal and wind comfort are estimated for the agents released in the urban environment. However, as the established biometeorological indices are only defined for stationary meteorological state, adaptation and possibly re-definition of these indices are required as the agents movement no longer provides stationary atmospheric conditions.