Icon class icon_class far fa-sticky-note icon_class_computed far fa-sticky-note Note kind CONVENTION Policy level STRICT Keywords Psychrometrics Webel::MPsy Webel::Psy thermodynamics heat energy transfer work thermodynamic work This corresponds to the convention adopted by Wikipedia Thermodynamics and many modern representations of the Carnot Engine Relates to TRAIL: Air Conditioning Psychrometrics (vs CED Engineering course): Example results (only) in Mathematica and SysML using the Webel Psy package and MPsy class SysML4Mathematica: Example 05: Sensible heating: 'qSen' (+ve): energy transfer TO humid air SysML4Mathematica: Example 06: Sensible heating: 'qSen' per mass (+ve): energy transfer TO humid air SysML4Mathematica: Example 07: Sensible cooling: 'qDotSen' (-ve): energy transfer rate FROM humid air SysML4Mathematica: Example 08a: Humidification: Drying lumber with air: required volumetric air flow rate SysML4Mathematica: Example 09: Moisture added to air: Amount (mass) SysML4Mathematica: Example 10: Condition and dehumidify air by chilling and condensing some moisture: Process table SysML4Mathematica: Example 11 [A] Total (qDotTot), sensible (qDotSen), and latent cooling (qDotLat) required for cooling air: Using CoolProp wrappers and SysML Parametric Diagrams SysML4Mathematica: Example 11 [B]: Total (qDotTot), sensible (qDotSen), and latent cooling (qDotLat) required for cooling air: Using Webel MPsy objects and SysML Activity Diagrams Related notes Related notes (backlinks) [CONVENTION, LIMITATION, MODELLING, NAMING, TOOL]{RECOMMENDED} Webel: Psy/MPsy: Psychrometrics for Mathematica: '$HC' in a function name indicates pure sensible heating or cooling (with no change in water vapour content). Such functions may also be used in the pure sensible portion of a 2-step treatment. [CONVENTION, NAMING]{INFORMATIVE} Webel: Psy/MPsy: Psychrometrics for Mathematica: Equation registry with variable/quantity markup [CONVENTION, NAMING]{INFORMATIVE} Webel: Psy/MPsy: Psychrometrics for Mathematica: Variable/quantity registry and naming conventions, with symbol markup. [EXPLANATION, FEATURE, POLICY]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: The default newPsy[tdb] builder accepts the pressure 'p' as an option, which defaults to sea level atmospheric pressure. [CONVENTION]{INFORMATIVE} Webel: Psy/MPsy: Psychrometrics for Mathematica: The CoolProp "wrappers" of the Psy library in fact wrap lower-level wrappers (bindings) for CoolProp for Mathematica [CAPABILITY, EXPLANATION]{INFORMATIVE} Webel: Psy/MPsy: Psychrometrics for Mathematica: The default MPsy class is a readonly one-shot class that pre-builds many frequently used psychrometric properties (offered as public fields) using CoolProp, and also offers some value-adding methods. [EXPLANATION, FEATURE, POLICY]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: The default newPsy[tdb] builder requires the dry bulb temperature 'tdb', and one (only) of the relative humidity 'r', the humidity ratio 'w', or the wet bulb temperature 'twb' (as options). [CONVENTION]{INFORMATIVE} Webel: Psy/MPsy: Psychrometrics for Mathematica: Most CoolProp wrappers can be invoked with the dry bulb temperature 'tdb', the pressure 'p', and one (only) of the relative humidity 'r', the humidity ratio 'w', or the wet bulb temperature 'twb' [CONVENTION]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: Due to Mathematica's units-aware Quantity algebra system it is irrelevant what units are used for the input Quantities for creation of the MPsy objects, as long as they are dimensionally consistent! [CONVENTION]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: Transferred heat (energy "Q") has field names with lower case 'qTot', 'qSen', 'qLat'. Heat rates (energy per time) have field names 'qDotTot', 'qDotSen', 'qDotLat' (to avoid clashes with Mathematica core) [CONVENTION]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: Relative humidity is indicated by a lower case 'r' and measured as a Real fraction (rather than as a Percentage). [Some tables and plots do SHOW the relative humidity as a Percentage.] [CONVENTION]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: For Imperial Units (IP), International British Thermal Units (Btu) are assumed [CONVENTION]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: Humidity ratio (absolute humidity) is indicated by a lower case 'w' and measured in mass (water) / mass (dry air) units, so the SI and IP representations are equal Real (without an explicit unit system) Related snippets (extracts) Visit also Visit also (backlinks) External links https://en.wikipedia.org/wiki/Thermodynamics https://en.wikipedia.org/wiki/Carnot_heat_engine Flags
