Single-zone office building
[Commercial buildings (commercial)]

Detailed Description

The building simultion uses a single zone ETP model with first order ODEs:.

$T'_i = \frac{1}{c_a} \left[ T_m h_m - T_i (UA-h_m) + \Sigma Q_x + T_o UA \right]$

$T'_m = \frac{h_m}{c_m} \left[ T_i - T_m \right]$

where:

is the temperature of the air inside the building
is $\frac{d}{dt}T_i$
is the temperature of the mass inside the buildnig (e.g, furniture, inside walls etc)
is $\frac{d}{dt}T_m$
is the ambient temperature outside air
is the UA of the building itself
is the UA of the mass of the furniture, inside walls etc
is the heat capacity of the mass of the furniture inside the walls etc
is the heat capacity of the air inside the building
is the heat rate from internal heat gains of the building (e.g., plugs, lights, people)
is the heat rate from HVAC unit
is the heat rate from the sun (solar heating through windows etc)

General first order ODEs (C1-C5 defined by inspection above):

$T'_i = T_i C_1 + T_m C_2 + C_3$

$T'_m = T_i C_4 + T_m C_5$

General form of second order ODE

$p_4 = p_1 T"_i + p_2 T'_i + p_3 T_i$

Solution to second order ODE for indoor and mass temperatures are

$T_i(t) = K_1 e^{r_1 t} + K_1 e^{r_2 t} + \frac{p4}{p3}$

$T_m(t) = \frac{T'_i(t) - C_1 T_i(t) - C_3}{C_2}$

where:

$K_1 = \frac{(r_1 T_o - r_1 \frac{p_4}{p_3} - T_o}{r_2-r_1}$
$K_2 = \frac{T_o - r_2 K_2}{r_1}$
$p_1 = \frac{1}{C_2}$
$p_2 = -\frac{C_5}{C_2} - \frac{C_1}{C_2}$
$p_3 = C_5 \frac{C_1}{C_2} - C_4$
$p_4 = -C_5 \frac{C_3}{C_2}$
is the elapsed time
is the temperature of the air inside the building at time
is , e.g initial temperature of the air inside the building
is e.g the initial temperature gradient of the air inside the building

Classes

class office

struct s_conditions

struct s_controls

struct s_enduse

struct s_hvac

struct s_hvacdesign

struct s_lighting

struct s_plugs

struct s_zonedata

Enumerations

enum HCMODE {
HC_OFF, HC_HEAT, HC_AUX, HC_COOL,
HC_ECON
}

Functions

int office::create ()

EXPORT int create_office (OBJECT **obj, OBJECT *parent)

int office::init (OBJECT *parent)

EXPORT int init_office (OBJECT *obj, OBJECT *parent)

office::office (MODULE *module)

TIMESTAMP office::plc (TIMESTAMP t0, TIMESTAMP t1)

EXPORT TIMESTAMP plc_office (OBJECT *obj, TIMESTAMP t1, PASSCONFIG pass)

TIMESTAMP office::presync (TIMESTAMP t0, TIMESTAMP t1)

TIMESTAMP office::sync (TIMESTAMP t0, TIMESTAMP t1)

EXPORT TIMESTAMP sync_office (OBJECT *obj, TIMESTAMP t1, PASSCONFIG pass)

Variables

static office * office::defaults = NULL

static CLASS * office::oclass = NULL

Enumeration Type Documentation

enum HCMODE

Enumerator:

HC_OFF	HVAC is off.
HC_HEAT	HVAC is heating.
HC_AUX	HVAC is supplemental heating.
HC_COOL	HVAC is cooling.
HC_ECON	HVAC is economizing.

Definition at line 27 of file office.h.

Function Documentation

int office::create ( ) [inherited]

Todo:: set the static initial value of properties (no ticket)

Definition at line 198 of file office.cpp.

References defaults.

Referenced by create_office().

int office::init ( OBJECT * parent ) [inherited]

Todo:: set the dynamic initial value of properties (no ticket)

Todo:: link climate data (no ticket)

Todo:: sanity check the initial values (no ticket)

Todo:: list simple tests to be made on data (no ticket)

Definition at line 206 of file office.cpp.

References s_hvacdesign::balance_temperature, s_plugs::capacity, s_lighting::capacity, s_hvacdesign::capacity, s_zonedata::control, s_hvac::cooling, s_controls::cooling_setpoint, s_hvacdesign::cop, s_zonedata::current, s_zonedata::design, s_hvacdesign::design_temperature, s_zonedata::exterior_ua, FL_NEW, s_zonedata::floor_area, s_zonedata::floor_height, FT_CLASS, FT_END, GETADDR, gl_find_next, gl_find_objects, gl_get_property, gl_set_dependent, gl_warning, s_zonedata::glazing_coeff, s_hvac::heating, s_controls::heating_setpoint, s_findlist::hit_count, s_zonedata::hvac, s_zonedata::interior_mass, s_zonedata::interior_ua, s_zonedata::lights, OBJECTHDR, s_conditions::pHumidity, s_zonedata::plugs, s_conditions::pSolar, s_conditions::pTemperature, s_object_list::rank, SAME, s_controls::setpoint_deadband, s_zonedata::window_area, and zone.

TIMESTAMP office::sync	(	TIMESTAMP	t0,
		TIMESTAMP	t1
	)			`[inherited]`

Todo:: compute solar gains (no ticket)

Definition at line 282 of file office.cpp.

References s_conditions::air_temperature, s_zonedata::current, s_zonedata::design, s_hvac::enduse, s_plugs::enduse, s_lighting::enduse, s_enduse::energy, s_zonedata::exterior_ua, s_zonedata::floor_area, s_zonedata::floor_height, s_zonedata::hvac, s_zonedata::interior_mass, s_zonedata::interior_ua, s_zonedata::lights, s_conditions::mass_temperature, s_hvac::mode, s_zonedata::plugs, s_enduse::power, s_conditions::pSolar, s_conditions::pTemperature, s_conditions::temperature_change, s_zonedata::total, TS_NEVER, TS_SECOND, s_zonedata::window_area, and zone.

Referenced by sync_office().

GridLAB-D^TM Version 1.0

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