HiRISE

HiRISE.HiPlan.HiTemp
Class Thermal_Model

java.lang.Object
  extended by HiRISE.HiPlan.HiTemp.Thermal_Model

public class Thermal_Model
extends Object

A thermal model for the HiRISE focal plane assembly (FPA) and focal plane electronics assembly (FPEA). Once instantiated, the model's computeTemperatures(HiRISE.HiPlan.HiTemp.Observation_Timeline, HiRISE.HiPlan.HiTemp.Thermal_Model.ModelParameters, HiRISE.HiPlan.HiTemp.Temperatures) method is used to generate the predicted temperatures for the focal plane components over a specified duration.

This class is based on the work of Jeff Lasco of Ball Aerospace and Laszlo Keszthelyi of the U.S. Geological Survey.

Version:
1.25
Author:
Christian Schaller - UA/PIRL
See Also:
"HiRISE Reduced TMM Description & Predictions vs. Flight Data For Three Events, J. Lasco, January 16, 2006"

Nested Class Summary
static class Thermal_Model.ModelParameters
          A set of HiTemp model parameters.
 
Field Summary
static double C_FPA
          The heat capacity of the focal plane assembly.
static double C_FPEA
          The heat capacity of the focal plane electronics assembly.
static double C_TO_K
          The conversion from Celsius degrees to Kelvin degrees.
static double DEFAULT_FPA_SET_POINT_TEMPERATURE
          The default set-point temperature of the focal plane assembly.
static double DEFAULT_FPEA_SET_POINT_TEMPERATURE
          The default set-point temperature of the focal plane electronics assembly.
static double DEFAULT_IEA_TEMPERATURE
          The default temperature of the interface electronics assembly.
static double DEFAULT_MRO_ENCLOSURE_TEMPERATURE
          The default temperature of the MRO enclosure.
static double DEFAULT_OPTICAL_BENCH_TEMPERATURE
          The default temperature of the optical bench.
static double F_FPA_MRO_ENCLOSURE
          The effective area for thermal radiation between the focal plane assembly and the MRO enclosure.
static double F_FPA_OPTICAL_BENCH
          The effective area for thermal radiation between the focal plane assembly and the optical bench.
static double F_FPEA_MRO_ENCLOSURE
          The effective area for thermal radiation between the focal plane electronics assembly and the MRO enclosure.
static String ID
          Class identification name with source code version and date.
static double K_FPA_FPEA
          The effective thermal conductivity between the focal plane assembly and the focal plane electronics assembly.
static double K_FPA_OPTICAL_BENCH
          The effective thermal conductivity between the focal plane assembly and the optical bench.
static double K_FPEA_OPTICAL_BENCH
          The effective thermal conductivity between the focal plane electronics assembly and the optical bench.
static double Q_FPA_HEATER_FACTOR
          An empirical multiplier factor for the focal plane assembly's heater power.
static double Q_FPA_HEATERS_ON
          The heat dissipated in the focal plane assembly when the heaters are on at 28 V.
static double Q_FPA_INSTRUMENT_ON
          The heat dissipated in the focal plane assembly when the HiRISE instrument is on.
static double Q_FPEA_HEATER_FACTOR
          An empirical multiplier factor for the focal plane electronics assembly's heater power.
static double Q_FPEA_HEATERS_ON
          The heat dissipated in the focal plane electronics assembly when the heaters are at 28 V.
static double Q_FPEA_INSTRUMENT_ON
          The heat dissipated in the focal plane electronics assembly when the HiRISE instrument is on.
static double STEFAN_BOLTZMANN
          The Stefan-Boltzmann constant.
 
Constructor Summary
Thermal_Model()
          Creates a new thermal model using default values for the system temperatures.
Thermal_Model(double fpaSetPointTemperature, double fpeaSetPointTemperature, double opticalBenchTemperature, double mroEnclosureTemperature, double mroBusVoltage)
          Creates a new thermal model with the specified system temperatures.
 
Method Summary
 Temperature_Profile computeTemperatures(Observation_Timeline timeline, Thermal_Model.ModelParameters modelParameters, Temperatures temperatures)
           
 double getFpaSetPointTemperature()
          Gets the current focal plane assembly set-point temperature for this thermal model.
 double getFpeaSetPointTemperature()
          Gets the current focal plane electronics assembly set-point temperature for this thermal model.
 double getMroEnclosureTemperature()
           
 double getOpticalBenchTemperature()
          Gets the current optical bench temperature for this thermal model.
 Voltages getVoltages()
          Gets the Voltages used in this thermal model.
static double ieaToMroEnclosure(double iea)
          Computes the MRO enclosure temperature from a given interface electronics assembly temperature.
 void setFpaSetPointTemperature(double fpaSetPointTemperature)
          Sets the current focal plane assembly set-point temperature for this thermal model.
 void setFpeaSetPointTemperature(double fpeaSetPointTemperature)
          Sets the current focal plane electronics assembly set-point temperature for this thermal model.
 void setMroEnclosureFromIea(double ieaTemperature)
          Sets the MRO enclosure temperature by deriving it from an interface electronics assembly temperature.
 void setMroEnclosureTemperature(double mroEnclosureTemperature)
          Sets the current MRO enclosure temperature used in this thermal model.
 void setOpticalBenchTemperature(double opticalBenchTemperature)
          Sets the current optical bench temperature for this thermal model.
 void setVoltages(Voltages voltages)
          Sets the Voltages used in this thermal model.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

ID

public static final String ID
Class identification name with source code version and date.

See Also:
Constant Field Values

Q_FPA_INSTRUMENT_ON

public static final double Q_FPA_INSTRUMENT_ON
The heat dissipated in the focal plane assembly when the HiRISE instrument is on. Units: W.

See Also:
Constant Field Values

Q_FPEA_INSTRUMENT_ON

public static final double Q_FPEA_INSTRUMENT_ON
The heat dissipated in the focal plane electronics assembly when the HiRISE instrument is on. Units: W.

See Also:
Constant Field Values

Q_FPA_HEATERS_ON

public static final double Q_FPA_HEATERS_ON
The heat dissipated in the focal plane assembly when the heaters are on at 28 V. The actual heat dissipated is a function of voltage, which ranges from 24 V to 36 V. The adjusted heat QV for a given voltage V is given by the following equation:

QV = Q28 * (V/28)2

Q28 is the heat at 28 V: Q_FPA_HEATERS_ON.

Units: W.

See Also:
Constant Field Values

Q_FPEA_HEATERS_ON

public static final double Q_FPEA_HEATERS_ON
The heat dissipated in the focal plane electronics assembly when the heaters are at 28 V. The actual heat dissipated is a function of voltage, which ranges from 24 V to 36 V. The adjusted heat QV for a given voltage V is given by the following equation:

QV = Q28 * (V/28)2

Q28 is the heat at 28 V: Q_FPEA_HEATERS_ON.

Units: W.

See Also:
Constant Field Values

Q_FPA_HEATER_FACTOR

public static final double Q_FPA_HEATER_FACTOR
An empirical multiplier factor for the focal plane assembly's heater power. The model is not quite accurate, and this factor can help fix it.

See Also:
Constant Field Values

Q_FPEA_HEATER_FACTOR

public static final double Q_FPEA_HEATER_FACTOR
An empirical multiplier factor for the focal plane electronics assembly's heater power. The model is not quite accurate, and this factor can help fix it.

See Also:
Constant Field Values

K_FPA_FPEA

public static final double K_FPA_FPEA
The effective thermal conductivity between the focal plane assembly and the focal plane electronics assembly. Units: W m^-1 K^-1.

See Also:
Constant Field Values

K_FPA_OPTICAL_BENCH

public static final double K_FPA_OPTICAL_BENCH
The effective thermal conductivity between the focal plane assembly and the optical bench. Units: W m^-1 K^-1.

See Also:
Constant Field Values

K_FPEA_OPTICAL_BENCH

public static final double K_FPEA_OPTICAL_BENCH
The effective thermal conductivity between the focal plane electronics assembly and the optical bench. Units: W m^-1 K^-1.

See Also:
Constant Field Values

F_FPA_OPTICAL_BENCH

public static final double F_FPA_OPTICAL_BENCH
The effective area for thermal radiation between the focal plane assembly and the optical bench. Units: m^2.

See Also:
Constant Field Values

F_FPA_MRO_ENCLOSURE

public static final double F_FPA_MRO_ENCLOSURE
The effective area for thermal radiation between the focal plane assembly and the MRO enclosure. Units: m^2.

See Also:
Constant Field Values

F_FPEA_MRO_ENCLOSURE

public static final double F_FPEA_MRO_ENCLOSURE
The effective area for thermal radiation between the focal plane electronics assembly and the MRO enclosure. Units: m^2.

See Also:
Constant Field Values

C_FPA

public static final double C_FPA
The heat capacity of the focal plane assembly. Units: J kg^-1.

See Also:
Constant Field Values

C_FPEA

public static final double C_FPEA
The heat capacity of the focal plane electronics assembly. Units: J kg^-1.

See Also:
Constant Field Values

STEFAN_BOLTZMANN

public static final double STEFAN_BOLTZMANN
The Stefan-Boltzmann constant. Units: W m^-2 K^-4.

See Also:
Constant Field Values

C_TO_K

public static final double C_TO_K
The conversion from Celsius degrees to Kelvin degrees. Add this value to a Celsius temperature to get a Kelvin temperature.

See Also:
Constant Field Values

DEFAULT_FPA_SET_POINT_TEMPERATURE

public static final double DEFAULT_FPA_SET_POINT_TEMPERATURE
The default set-point temperature of the focal plane assembly. The FPA is nominally maintained between 18.3 and 18.7 degrees Celsius. Units: C.

See Also:
Constant Field Values

DEFAULT_FPEA_SET_POINT_TEMPERATURE

public static final double DEFAULT_FPEA_SET_POINT_TEMPERATURE
The default set-point temperature of the focal plane electronics assembly. The FPEA is nominally maintained at around 18.5 degrees Celsius (revised 8/2017 from 18.3). Units: C.

See Also:
Constant Field Values

DEFAULT_OPTICAL_BENCH_TEMPERATURE

public static final double DEFAULT_OPTICAL_BENCH_TEMPERATURE
The default temperature of the optical bench. The optical bench temperature is nominally between 22.0 and 23.0 degrees Celsius (revised 8/2017 from 19.5 to 21.0). Units: C.

See Also:
Constant Field Values

DEFAULT_IEA_TEMPERATURE

public static final double DEFAULT_IEA_TEMPERATURE
The default temperature of the interface electronics assembly. This IEA temperature (26 degrees Celsius) corresponds to an MRO enclosure/mid-deck temperature of roughly 1.5 degrees Celsius. Units: C.

See Also:
ieaToMroEnclosure(double), Constant Field Values

DEFAULT_MRO_ENCLOSURE_TEMPERATURE

public static final double DEFAULT_MRO_ENCLOSURE_TEMPERATURE
The default temperature of the MRO enclosure. For the primary science phase (PSP), this temperature nominally varies from -28.0 to 1.0 degrees Celsius. Units: C.

See Also:
Constant Field Values
Constructor Detail

Thermal_Model

public Thermal_Model(double fpaSetPointTemperature,
                     double fpeaSetPointTemperature,
                     double opticalBenchTemperature,
                     double mroEnclosureTemperature,
                     double mroBusVoltage)
Creates a new thermal model with the specified system temperatures.

Parameters:
fpaSetPointTemperature - the set-point temperature for the focal plane assembly.
fpeaSetPointTemperature - the set-point temperature for the focal plane electronics assembly.
opticalBenchTemperature - the temperature of the optical bench.
mroEnclosureTemperature - the temperature of the MRO enclosure.
mroBusVoltage - the voltage of the MRO bus, which powers the HiRISE heaters.

Thermal_Model

public Thermal_Model()
Creates a new thermal model using default values for the system temperatures.

See Also:
DEFAULT_FPA_SET_POINT_TEMPERATURE, DEFAULT_FPEA_SET_POINT_TEMPERATURE, DEFAULT_OPTICAL_BENCH_TEMPERATURE, DEFAULT_MRO_ENCLOSURE_TEMPERATURE, Voltages.DEFAULT_MRO_BUS_VOLTAGE
Method Detail

getFpaSetPointTemperature

public double getFpaSetPointTemperature()
Gets the current focal plane assembly set-point temperature for this thermal model.

Returns:
this model's focal plane assembly set-point temperature in degrees Celsius.

setFpaSetPointTemperature

public void setFpaSetPointTemperature(double fpaSetPointTemperature)
Sets the current focal plane assembly set-point temperature for this thermal model.

Parameters:
fpaSetPointTemperature - the new focal plane assembly set-point temperature for this model in degrees Celsius.

getFpeaSetPointTemperature

public double getFpeaSetPointTemperature()
Gets the current focal plane electronics assembly set-point temperature for this thermal model.

Returns:
this model's focal plane electronics assembly set-point temperature in degrees Celsius.

setFpeaSetPointTemperature

public void setFpeaSetPointTemperature(double fpeaSetPointTemperature)
Sets the current focal plane electronics assembly set-point temperature for this thermal model.

Parameters:
fpeaSetPointTemperature - the new focal plane electronics assembly set-point temperature for this model in degrees Celsius.

getOpticalBenchTemperature

public double getOpticalBenchTemperature()
Gets the current optical bench temperature for this thermal model.

Returns:
the optical bench temperature for this model in degrees Celsius.

setOpticalBenchTemperature

public void setOpticalBenchTemperature(double opticalBenchTemperature)
Sets the current optical bench temperature for this thermal model.

Parameters:
opticalBenchTemperature - the new optical bench temperature for this model in degrees Celsius.

getMroEnclosureTemperature

public double getMroEnclosureTemperature()

setMroEnclosureTemperature

public void setMroEnclosureTemperature(double mroEnclosureTemperature)
Sets the current MRO enclosure temperature used in this thermal model.

Parameters:
mroEnclosureTemperature - the new MRO enclosure temperature for this model in degrees Celsius.

getVoltages

public Voltages getVoltages()
Gets the Voltages used in this thermal model.

Returns:
the voltages for this model.

setVoltages

public void setVoltages(Voltages voltages)
Sets the Voltages used in this thermal model.

Parameters:
voltages - the new voltages for this model.

setMroEnclosureFromIea

public void setMroEnclosureFromIea(double ieaTemperature)
Sets the MRO enclosure temperature by deriving it from an interface electronics assembly temperature.

Parameters:
ieaTemperature - the IEA temperature in degrees Celsius.
See Also:
ieaToMroEnclosure(double)

computeTemperatures

public Temperature_Profile computeTemperatures(Observation_Timeline timeline,
                                               Thermal_Model.ModelParameters modelParameters,
                                               Temperatures temperatures)

ieaToMroEnclosure

public static double ieaToMroEnclosure(double iea)
Computes the MRO enclosure temperature from a given interface electronics assembly temperature.

The following equation handles the conversion, as supplied by Jeff Lasco:

TMRO + 273.15 = ((TIEA + 273.15)4 - 2313642982)1/4

Temperatures are in degrees Celsius.

The IEA temperature can be derived from measurements of the T-0034 and T-0234 sensors; an average of the two may be used.

Parameters:
iea - the IEA temperature in degrees Celsius.
Returns:
the MRO enclosure temperature in degrees Celsius.

HiRISE

Copyright (C) Arizona Board of Regents on behalf of the Planetary Image Research Laboratory, Lunar and Planetary Laboratory at the University of Arizona