fgdata/Aircraft/c172p/Systems/c172p-engine.xml

<?xml version="1.0"?>

<!--

  c172p damage effects for JSBSim.

    Copyright (c) 2015 Gilberto Agostinho

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-->

<system name="engine">

    <channel name="oil">

        <fcs_function name="consumed-oil-weight">
            <function>
                <product>
                    <property>/engines/active-engine/oil-lacking</property>
                    <value>1.7686</value>
                    <value>-1</value>
                </product>
            </function>
            <output>/fdm/jsbsim/inertia/pointmass-weight-lbs[16]</output>
        </fcs_function>

    </channel>

    <channel name="carburetor">

        <fcs_function name="Carb heat on causes RPM drop on 160 HP engine">
            <function>
                <ifthen>
                    <property>/controls/anti-ice/engine[0]/carb-heat</property>
                    <value>0.475</value>
                    <value>0.15185</value>
                </ifthen>
            </function>
            <output>/fdm/jsbsim/propulsion/engine[0]/air-intake-impedance-factor</output>
        </fcs_function>

        <fcs_function name="Carb heat on causes RPM drop on 180 HP engine">
            <function>
                <ifthen>
                    <property>/controls/anti-ice/engine[1]/carb-heat</property>
                    <value>0.475</value>
                    <value>0.15185</value>
                </ifthen>
            </function>
            <output>/fdm/jsbsim/propulsion/engine[1]/air-intake-impedance-factor</output>
        </fcs_function>

    </channel>

    <channel name="damage">
        <fcs_function name="engine/rpm-over-redline">
            <function>
                <sum>
                    <property>/engines/active-engine/rpm</property>
                    <value>-2750</value>
                    <property>engine/rpm-over-redline-offset</property>
                </sum>
            </function>
            <clipto>
                <min>0</min>
                <max>10000</max>
            </clipto>
        </fcs_function>
        
        <fcs_function name="engine/rpm-over-redline-offset"> <!-- reduce the damage threshold as damage increases -->
              <function>
                <product>
                    <pow>
                        <property>engine/damage-level</property>
                        <value>2</value>
                    </pow>
                    <value>0.00075</value>
                </product>
            </function>
            <clipto>
                <min>0</min>
                <max>10000</max>
            </clipto>
        </fcs_function>
        
        <fcs_function name="engine/oil-temp-above-max">
            <function>
                <sum>
                    <property>/engines/active-engine/oil-temperature-degf</property>
                    <value>-245</value>
                </sum>
            </function>
            <clipto>
                <min>0</min>
                <max>1000</max>
            </clipto>
        </fcs_function>

        <fcs_function name="engine-damage"> <!-- it0uchpods suggests this to allow repair button to reset to 0 -->
              <function>
                <ifthen>
                    <and>
                        <eq>
                            <property>settings/damage</property>
                            <value>1</value>
                        </eq>
                        <eq>
                            <property>/engines/active-engine/damage_allowed</property>
                            <value>1</value>
                        </eq>
                    </and>
                    <sum>
                        <property>engine/damage-level</property>
                        <product>
                           <table>
                                <independentVar lookup="row">engine/rpm-over-redline</independentVar>
                                <independentVar lookup="column">engine/oil-temp-above-max</independentVar>
                                <tableData>
                                         0     50    100    250
                                    0    0      1      9     16
                                  100    1      2     16     50
                                  200    4      5     25     65
                                  300    9     10     36     82
                                  400   16     17     49    101
                                  500   25     25     64    122
                                  600   36     37     81    145
                                  700   49     50    100    170
                                  800   64     65    121    197
                                  900   81     82    144    226
                                 1000  100    101    169    256
                                 1100  121    123    196    289
                                 1200  144    147    225    324
                                 1300  169    175    256    361
                                 1400  196    199    289    400
                                 1500  225    228    324    441
                                </tableData>
                            </table>
                            <property>simulation/channel-dt</property>
                        </product>
                    </sum>
                    <value>0</value> <!-- this is the value if damage is disabled -->
                </ifthen>
            </function>
            <output>engine/damage-level</output>
        </fcs_function>

        <fcs_function>
            <function> <!-- derived from a graphical calculator: 0.01x pow 2 + 2.15x + 0.625 multiplied by 2.4 -->
                <product>
                    <sum>
                        <product>
                            <value>0.00008</value>
                            <pow>
                                <property>engine/damage-level</property>
                                <value>2</value>
                            </pow>
                        </product>
                        <value>0.625</value>
                    </sum>
                    <value>2.4</value>
                </product>
            </function>
            <clipto>
                <min>1.5</min>
                <max>10000</max>
            </clipto>
            <output>engine/friction-hp</output>
        </fcs_function>

        <switch name="engine/engine-0-friction-hp">
            <default value="1.5"/>
            <test  logic="AND" value="engine/friction-hp">
                /controls/engines/active-engine eq 0
            </test>
            <output>/fdm/jsbsim/propulsion/engine[0]/friction-hp</output>
        </switch>

         <switch name="engine/engine-1-friction-hp">
            <default value="1.5"/>
            <test  logic="AND" value="engine/friction-hp">
                /controls/engines/active-engine eq 1
            </test>
            <output>/fdm/jsbsim/propulsion/engine[1]/friction-hp</output>
        </switch>
        
        <switch name="engine/damage-smoke">
            <default value="0"/>
            <test  logic="AND" value="1">
                /fdm/jsbsim/engine/damage-level GT 100
                /engines/active-engine/running EQ 1
            </test>
            <output>/aircraft/effects/damage-smoke-visible</output>
        </switch>

        <fcs_function name="auto-engine-mixture">
            <function> <!-- Mixture rich above 3000 feet, LEAN to obtain maximum RPM -->
                <sum>
                    <value>0</value>
                    <table>
                        <independentVar>/position/altitude-ft</independentVar>
                        <tableData>
                            3000    1.00
                            13000   0.75
                        </tableData>
                    </table>
                </sum>
            </function>
            <output>engine/auto-mixture</output>
        </fcs_function>

    </channel>
</system>