diff --git a/examples/AgoraDisk/agora_disk.yml b/examples/AgoraDisk/agora_disk.yml
index 7368700d8a2a5ca8de7d677e1da78be51d669835..4870d29a7b6caaaa8b574b16cd6b453b8d3b3dad 100644
--- a/examples/AgoraDisk/agora_disk.yml
+++ b/examples/AgoraDisk/agora_disk.yml
@@ -39,7 +39,7 @@ Gravity:
SPH:
resolution_eta: 1.2348 # Target smoothing length in units of the mean inter-particle separation (1.2348 == 48Ngbs with the cubic spline kernel).
CFL_condition: 0.1 # Courant-Friedrich-Levy condition for time integration.
- minimal_temperature: 10 # (internal units)
+ minimal_temperature: 10. # Kelvin
# Parameters related to the initial conditions
InitialConditions:
@@ -50,9 +50,6 @@ InitialConditions:
# Dimensionless pre-factor for the time-step condition
LambdaCooling:
lambda_cgs: 1.0e-22 # Cooling rate (in cgs units)
- minimum_temperature: 1.0e2 # Minimal temperature (Kelvin)
- mean_molecular_weight: 0.59 # Mean molecular weight
- hydrogen_mass_abundance: 0.75 # Hydrogen mass abundance (dimensionless)
cooling_tstep_mult: 1.0 # Dimensionless pre-factor for the time-step condition
# Cooling with Grackle 2.0
diff --git a/examples/CoolingBox/coolingBox.yml b/examples/CoolingBox/coolingBox.yml
index 2bd2f19f6d78388ae638521f590255d410bc8697..510bcd63170206b71d8e2a63174da9e4abdbbccb 100644
--- a/examples/CoolingBox/coolingBox.yml
+++ b/examples/CoolingBox/coolingBox.yml
@@ -27,6 +27,7 @@ Statistics:
SPH:
resolution_eta: 1.2348 # Target smoothing length in units of the mean inter-particle separation (1.2348 == 48Ngbs with the cubic spline kernel).
CFL_condition: 0.1 # Courant-Friedrich-Levy condition for time integration.
+ minimal_temperature: 100. # Kelvin
# Parameters related to the initial conditions
InitialConditions:
@@ -35,9 +36,6 @@ InitialConditions:
# Dimensionless pre-factor for the time-step condition
LambdaCooling:
lambda_cgs: 1.0e-22 # Cooling rate (in cgs units)
- minimum_temperature: 1.0e4 # Minimal temperature (Kelvin)
- mean_molecular_weight: 0.59 # Mean molecular weight
- hydrogen_mass_abundance: 0.75 # Hydrogen mass abundance (dimensionless)
cooling_tstep_mult: 1.0 # Dimensionless pre-factor for the time-step condition
# Cooling with Grackle 2.0
diff --git a/examples/CoolingHalo/cooling_halo.yml b/examples/CoolingHalo/cooling_halo.yml
index 68c3478b717261698ac175835fc246e134e3a6a7..2ae0c9ddd4e1bfaf5ce5686b28dca32a166b7d7b 100644
--- a/examples/CoolingHalo/cooling_halo.yml
+++ b/examples/CoolingHalo/cooling_halo.yml
@@ -27,7 +27,8 @@ Snapshots:
SPH:
resolution_eta: 1.2349 # Target smoothing length in units of the mean inter-particle separation (1.2349 == 48Ngbs with the cubic spline kernel).
CFL_condition: 0.1 # Courant-Friedrich-Levy condition for time integration.
-
+ minimal_temperature: 1e4 # Kelvin
+
# Parameters related to the initial conditions
InitialConditions:
file_name: CoolingHalo.hdf5 # The file to read
@@ -41,7 +42,4 @@ IsothermalPotential:
# Cooling parameters
LambdaCooling:
lambda_cgs: 1.0e-22 # Cooling rate (in cgs units)
- minimum_temperature: 1.0e4 # Minimal temperature (Kelvin)
- mean_molecular_weight: 0.59 # Mean molecular weight
- hydrogen_mass_abundance: 0.75 # Hydrogen mass abundance (dimensionless)
cooling_tstep_mult: 1.0 # Dimensionless pre-factor for the time-step condition
diff --git a/examples/CoolingHaloWithSpin/cooling_halo.yml b/examples/CoolingHaloWithSpin/cooling_halo.yml
index f6e9fe3b124631fc2d5336db8a7ffb18f7b34a95..1b173dea8c30e7e9a75527d8fdbb76bc45997e89 100644
--- a/examples/CoolingHaloWithSpin/cooling_halo.yml
+++ b/examples/CoolingHaloWithSpin/cooling_halo.yml
@@ -27,6 +27,7 @@ Snapshots:
SPH:
resolution_eta: 1.2349 # Target smoothing length in units of the mean inter-particle separation (1.2349 == 48Ngbs with the cubic spline kernel).
CFL_condition: 0.1 # Courant-Friedrich-Levy condition for time integration.
+ minimal_temperature: 1e4 # Kelvin
# Parameters related to the initial conditions
InitialConditions:
@@ -41,7 +42,4 @@ IsothermalPotential:
# Cooling parameters
LambdaCooling:
lambda_cgs: 1.0e-22 # Cooling rate (in cgs units)
- minimum_temperature: 1.0e4 # Minimal temperature (Kelvin)
- mean_molecular_weight: 0.59 # Mean molecular weight
- hydrogen_mass_abundance: 0.75 # Hydrogen mass abundance (dimensionless)
cooling_tstep_mult: 0.1 # Dimensionless pre-factor for the time-step condition
diff --git a/examples/SmallCosmoVolume_cooling/README b/examples/SmallCosmoVolume_cooling/README
index a0abad5f814f87133dccc31d414bdc546609df88..2ee364ca2f00a4280a492a11520bf7b9a1ac1f7d 100644
--- a/examples/SmallCosmoVolume_cooling/README
+++ b/examples/SmallCosmoVolume_cooling/README
@@ -7,6 +7,11 @@ on the options to cancel the h-factors and a-factors at reading time.
We generate gas from the ICs using SWIFT's internal mechanism and set the
temperature to the expected gas temperature at this redshift.
+This example runs with cooling switch on. Depending on the cooling
+model chosen at the time SWIFT was configured, the answer will be
+different. Interesting cases to compare to the no-cooling case are
+a constant cooling rate or Compton cooling.
+
The 'plotTempEvolution.py' plots the temperature evolution of the gas
in the simulated volume.
diff --git a/examples/SmallCosmoVolume_cooling/small_cosmo_volume.yml b/examples/SmallCosmoVolume_cooling/small_cosmo_volume.yml
index 8f6a2f2ad6a972e6bc1523da80b4243495853ace..d087cac4e8ef01ca25c8d4329e1da92b4e38256a 100644
--- a/examples/SmallCosmoVolume_cooling/small_cosmo_volume.yml
+++ b/examples/SmallCosmoVolume_cooling/small_cosmo_volume.yml
@@ -59,5 +59,4 @@ InitialConditions:
# Constant lambda cooling function
LambdaCooling:
- lambda_cgs: 1e-30 # Cooling rate (in cgs units)
- cooling_tstep_mult: 1.0 # Dimensionless pre-factor for the time-step condition
+ lambda_cgs: 1e-26 # Cooling rate (in cgs units)
diff --git a/examples/parameter_example.yml b/examples/parameter_example.yml
index 0b0a1c50d73663e695571faa4e555c50d5bc242d..1f146d908521f298782eb0a81ebc804773ea625c 100644
--- a/examples/parameter_example.yml
+++ b/examples/parameter_example.yml
@@ -199,10 +199,7 @@ ConstCooling:
# Constant lambda cooling function
LambdaCooling:
lambda_cgs: 2.0 # Cooling rate (in cgs units)
- minimum_temperature: 1.0e4 # Minimal temperature (Kelvin)
- mean_molecular_weight: 0.59 # Mean molecular weight
- hydrogen_mass_abundance: 0.75 # Hydrogen mass abundance (dimensionless)
- cooling_tstep_mult: 1.0 # Dimensionless pre-factor for the time-step condition
+ cooling_tstep_mult: 1.0 # (Optional) Dimensionless pre-factor for the time-step condition.
# Cooling with Grackle 3.0
GrackleCooling:
diff --git a/src/cooling/const_lambda/cooling.h b/src/cooling/const_lambda/cooling.h
index 57b58fed798dd68b5d7438f836bc005191c785e7..c1f5d802e441b69988fb6401e9398a925d8f55d4 100644
--- a/src/cooling/const_lambda/cooling.h
+++ b/src/cooling/const_lambda/cooling.h
@@ -159,6 +159,11 @@ __attribute__((always_inline)) INLINE static float cooling_timestep(
const struct unit_system* restrict us,
const struct hydro_props* hydro_props, const struct part* restrict p) {
+ /* Start with the case where there is no limit */
+ if (cooling->cooling_tstep_mult == FLT_MAX) {
+ return FLT_MAX;
+ }
+
/* Get current internal energy and cooling rate */
const float u = hydro_get_physical_internal_energy(p, cosmo);
const double cooling_du_dt_cgs =
@@ -225,8 +230,8 @@ static INLINE void cooling_init_backend(struct swift_params* parameter_file,
/* Read in the cooling parameters */
cooling->lambda_cgs =
parser_get_param_double(parameter_file, "LambdaCooling:lambda_cgs");
- cooling->cooling_tstep_mult = parser_get_param_double(
- parameter_file, "LambdaCooling:cooling_tstep_mult");
+ cooling->cooling_tstep_mult = parser_get_opt_param_float(
+ parameter_file, "LambdaCooling:cooling_tstep_mult", FLT_MAX);
/* Some useful conversion values */
cooling->conv_factor_density_to_cgs =
@@ -251,6 +256,12 @@ static INLINE void cooling_print_backend(
message("Cooling function is 'Constant lambda' with Lambda=%g [cgs]",
cooling->lambda_cgs);
+
+ if (cooling->cooling_tstep_mult == FLT_MAX)
+ message("Cooling function time-step size is unlimited");
+ else
+ message("Cooling function time-step size limited to %f of u/(du/dt)",
+ cooling->cooling_tstep_mult);
}
#endif /* SWIFT_COOLING_CONST_LAMBDA_H */
diff --git a/src/runner.c b/src/runner.c
index 0cf5a5da4ae64504e89a2136ab6d8ec8a1a8d191..2cd978a0185484a0daf4275a6b7c98ab033b96a5 100644
--- a/src/runner.c
+++ b/src/runner.c
@@ -461,11 +461,11 @@ void runner_do_cooling(struct runner *r, struct cell *c, int timer) {
if (part_is_active(p, e)) {
double dt_cool, dt_therm;
- ;
if (with_cosmology) {
const integertime_t ti_step = get_integer_timestep(p->time_bin);
const integertime_t ti_begin =
- get_integer_time_begin(ti_current + 1, p->time_bin);
+ get_integer_time_begin(ti_current - 1, p->time_bin);
+
dt_cool =
cosmology_get_delta_time(cosmo, ti_begin, ti_begin + ti_step);
dt_therm = cosmology_get_therm_kick_factor(e->cosmology, ti_begin,