bev thermal demo runs!

cal_and_val/thermal/f3-vehicles/2020 Chevrolet Bolt EV.yaml

@@ -36,9 +36,12 @@ pt_type:
     res:
       thrml: 
         RESLumpedThermal:
-          heat_capacitance_joules_per_kelvin: 0.0
-          htc_to_amb_watts_per_kelvin: 0.0
-          htc_to_cab_watts_per_kelvin: 0.0
+          # 200,000 is Chad's uncalibrated estimate
+          heat_capacitance_joules_per_kelvin: 200000
+          # 0.1 is Chad's uncalibrated estimate
+          conductance_to_amb_watts_per_kelvin: 0.1
+          # 0.5 is Chad's uncalibrated estimate
+          conductance_to_cab_watts_per_kelvin: 0.5
       mass_kilograms: ~
       specific_energy_joules_per_kilogram: ~
       pwr_out_max_watts: 165000.0

fastsim-core/src/vehicle/hvac/hvac_sys_for_lumped_cabin_and_res.rs

@@ -112,13 +112,15 @@ impl HVACSystemForLumpedCabinAndRES {
         dt: si::Time,
     ) -> anyhow::Result<(si::Power, si::Power, si::Power)> {
         let (res_temp, res_temp_prev) = res_temps;
+        ensure!(!res_temp.is_nan(), format_dbg!(res_temp));
+        ensure!(!res_temp_prev.is_nan(), format_dbg!(res_temp_prev));
         let mut pwr_thrml_hvac_to_cabin = self
             .solve_for_cabin(te_fc, cab_state, cab_heat_cap, dt)
             .with_context(|| format_dbg!())?;
         let mut pwr_thrml_hvac_to_res: si::Power = self
             .solve_for_res(res_temp, res_temp_prev, dt)
             .with_context(|| format_dbg!())?;
-        let cop_ideal: si::Ratio =
+        let (cop_ideal, te_ref) =
             if pwr_thrml_hvac_to_res + pwr_thrml_hvac_to_cabin > si::Power::ZERO {
                 // heating mode
                 // TODO: account for cabin and battery heat sources in COP calculation!!!!
@@ -151,9 +153,9 @@ impl HVACSystemForLumpedCabinAndRES {
                 if te_delta_vs_amb.abs() < 5.0 * uc::KELVIN {
                     // cabin is cooler than ambient + threshold
                     // TODO: make this `5.0` not hardcoded
-                    te_ref / (5.0 * uc::KELVIN)
+                    (te_ref / (5.0 * uc::KELVIN), te_ref)
                 } else {
-                    te_ref / te_delta_vs_amb.abs()
+                    (te_ref / te_delta_vs_amb.abs(), te_ref)
                 }
             } else if pwr_thrml_hvac_to_res + pwr_thrml_hvac_to_cabin < si::Power::ZERO {
                 // cooling mode
@@ -186,15 +188,20 @@ impl HVACSystemForLumpedCabinAndRES {
                 if te_delta_vs_amb.abs() < 5.0 * uc::KELVIN {
                     // cooling-dominating component is cooler than ambient + threshold
                     // TODO: make this `5.0` not hardcoded
-                    te_ref / (5.0 * uc::KELVIN)
+                    (te_ref / (5.0 * uc::KELVIN), te_ref)
                 } else {
-                    te_ref / te_delta_vs_amb.abs()
+                    (te_ref / te_delta_vs_amb.abs(), te_ref)
                 }
             } else {
-                si::Ratio::ZERO
+                (si::Ratio::ZERO, f64::NAN * uc::KELVIN)
             };
         self.state.cop = cop_ideal * self.frac_of_ideal_cop;
-        ensure!(self.state.cop >= 0.0 * uc::R, "{}", format_dbg!(cop_ideal));
+        ensure!(
+            self.state.cop >= 0.0 * uc::R,
+            "{}\n{}",
+            format_dbg!(cop_ideal),
+            format_dbg!(te_ref)
+        );
 
         let mut pwr_thrml_fc_to_cabin = si::Power::ZERO;
         self.state.pwr_aux_for_hvac = if pwr_thrml_hvac_to_cabin > si::Power::ZERO {

fastsim-core/src/vehicle/powertrain/reversible_energy_storage.rs

@@ -770,9 +770,9 @@ pub struct RESLumpedThermal {
     /// [ReversibleEnergyStorage] thermal capacitance
     pub heat_capacitance: si::HeatCapacity,
     /// parameter for heat transfer coeff from [ReversibleEnergyStorage::thrml] to ambient
-    pub htc_to_amb: si::ThermalConductance,
+    pub conductance_to_amb: si::ThermalConductance,
     /// parameter for heat transfer coeff from [ReversibleEnergyStorage::thrml] to cabin
-    pub htc_to_cab: si::ThermalConductance,
+    pub conductance_to_cab: si::ThermalConductance,
     /// current state
     #[serde(default, skip_serializing_if = "EqDefault::eq_default")]
     pub state: RESLumpedThermalState,
@@ -797,8 +797,9 @@ impl RESLumpedThermal {
         dt: si::Time,
     ) -> anyhow::Result<()> {
         self.state.temp_prev = self.state.temperature;
-        self.state.pwr_thrml_from_cabin = self.htc_to_cab * (te_cab - self.state.temperature);
-        self.state.pwr_thrml_from_amb = self.htc_to_cab * (te_amb - self.state.temperature);
+        self.state.pwr_thrml_from_cabin =
+            self.conductance_to_cab * (te_cab - self.state.temperature);
+        self.state.pwr_thrml_from_amb = self.conductance_to_cab * (te_amb - self.state.temperature);
         self.state.temperature += (pwr_thrml_hvac_to_res
             + res_state.pwr_out_electrical * (1.0 * uc::R - res_state.eff)
             + self.state.pwr_thrml_from_cabin

python/fastsim/demos/demo_bev_thrml.py

@@ -16,8 +16,6 @@
 
 from plot_utils  import *
 
-# if enivronment var `DEBUG_LOG=true` is set, turns on debug logging
-DEBUG_LOG = os.environ.get("DEBUG_LOG", "false").lower() == "true"     
 # if environment var `SHOW_PLOTS=false` is set, no plots are shown
 SHOW_PLOTS = os.environ.get("SHOW_PLOTS", "true").lower() == "true"     
 # if environment var `SAVE_FIGS=true` is set, save plots
@@ -27,7 +25,9 @@
 # %%
 
 # load 2012 Ford Fusion from file
-veh = fsim.Vehicle.from_file(fsim.package_root() / "../../cal_and_val/thermal/f3-vehicles/2020 Chevrolet Bolt EV.yaml")
+veh = fsim.Vehicle.from_file(
+    fsim.package_root() / "../../cal_and_val/thermal/f3-vehicles/2020 Chevrolet Bolt EV.yaml"
+)
 
 # Set `save_interval` at vehicle level -- cascades to all sub-components with time-varying states
 fsim.set_param_from_path(veh, "save_interval" , 1)
@@ -41,13 +41,7 @@
 # simulation start time
 t0 = time.perf_counter()
 # run simulation
-# toggle commented code to enable logging
-if DEBUG_LOG:
-    print('Running `sd.walk()` with debug logging')
-    with fsim.utils.with_logging():
-        sd.walk()
-else:
-    sd.walk()
+sd.walk()
 # simulation end time
 t1 = time.perf_counter()
 t_fsim3_si1 = t1 - t0