1 /* Copyright (c) 2023. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
5 #include <simgrid/Exception.hpp>
6 #include <simgrid/plugins/chiller.hpp>
7 #include <simgrid/plugins/energy.h>
8 #include <simgrid/simix.hpp>
9 #include <xbt/asserts.h>
12 #include "src/kernel/resource/CpuImpl.hpp"
13 #include "src/simgrid/module.hpp"
15 SIMGRID_REGISTER_PLUGIN(chiller, "Chiller management", nullptr)
17 /** @defgroup plugin_chiller Plugin Chiller
21 This is the chiller plugin, enabling management of chillers.
26 A chiller is placed inside a room with several machines. The role of the chiller is to keep the temperature of the room
27 below a threshold. This plugin and its equations are based on the paper "Co-simulation of FMUs and Distributed
28 Applications with SimGrid" by Camus et al. (https://hal.science/hal-01762540).
30 The heat generated inside the room :math:`Q_{room}` depends on the heat from the machines :math:`Q_{machines}` and
31 from the heat of the other devices, such as lighing, accounted using a factor :math:`\alpha` such as:
35 Q_{room} = (1 + \alpha) \times Q_{machines}
37 This energy heats the input temperature :math:`T_{in}` and gives an output temperature :math:`T_{out}` based on the
38 mass of air inside the room :math:`m_{air}` and its specific heat :math:`C_{p}`:
42 T_{out} = T_{in} + {Q_{room} \over m_{air} \times C_{p}}
44 If the output temperature is above the goal temperature :math:`T_{goal}` the chiller compensates the excessive heat
45 using electrical energy :math:`Q_{cooling}` depending on its cooling efficiency :math:`\eta_{cooling}` :
49 Q_{cooling} = (T_{out} - T_{goal}) \times m_{air} \times C_{p} / \eta_{cooling}
51 The chiller has a power threshold that cannot be exceeded. If the power needed is above this threshold, or if the
52 chiller is not active, the temperature of the room increases.
57 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(Chiller, kernel, "Logging specific to the solar panel plugin");
59 namespace simgrid::plugins {
63 ChillerModel::ChillerModel() : Model("ChillerModel") {}
65 void ChillerModel::add_chiller(ChillerPtr c)
67 chillers_.push_back(c);
70 void ChillerModel::update_actions_state(double now, double delta)
72 for (auto chiller : chillers_)
76 double ChillerModel::next_occurring_event(double now)
78 static bool init = false;
88 std::shared_ptr<ChillerModel> Chiller::chiller_model_;
90 void Chiller::init_plugin()
92 auto model = std::make_shared<ChillerModel>();
93 simgrid::s4u::Engine::get_instance()->add_model(model);
94 Chiller::chiller_model_ = model;
97 void Chiller::update()
99 simgrid::kernel::actor::simcall_answered([this] {
100 double now = s4u::Engine::get_clock();
101 double time_delta_s = now - last_updated_;
103 if (time_delta_s <= 0)
106 double hosts_power_w = 0;
107 for (auto const& host : hosts_) {
108 hosts_power_w += sg_host_get_current_consumption(host);
111 double heat_generated_j = hosts_power_w * (1 + alpha_) * time_delta_s;
112 temp_out_c_ = temp_in_c_ + heat_generated_j / (air_mass_kg_ * specific_heat_j_per_kg_per_c_);
113 double cooling_demand_w =
114 std::max(temp_out_c_ - goal_temp_c_, 0.0) * air_mass_kg_ * specific_heat_j_per_kg_per_c_ / time_delta_s;
118 power_w_ = std::min(max_power_w_, cooling_demand_w / cooling_efficiency_);
120 temp_out_c_ - (power_w_ * time_delta_s * cooling_efficiency_) / (air_mass_kg_ * specific_heat_j_per_kg_per_c_);
121 energy_consumed_j_ += power_w_ * time_delta_s;
126 Chiller::Chiller(const std::string& name, double air_mass_kg, double specific_heat_j_per_kg_per_c, double alpha,
127 double cooling_efficiency, double initial_temp_c, double goal_temp_c, double max_power_w)
129 , air_mass_kg_(air_mass_kg)
130 , specific_heat_j_per_kg_per_c_(specific_heat_j_per_kg_per_c)
132 , cooling_efficiency_(cooling_efficiency)
133 , temp_in_c_(initial_temp_c)
134 , temp_out_c_(initial_temp_c)
135 , goal_temp_c_(goal_temp_c)
136 , max_power_w_(max_power_w)
138 xbt_assert(air_mass_kg > 0, ": air mass must be > 0 (provided: %f)", air_mass_kg);
139 xbt_assert(specific_heat_j_per_kg_per_c > 0, ": specific heat must be > 0 (provided: %f)",
140 specific_heat_j_per_kg_per_c);
141 xbt_assert(alpha >= 0, ": alpha must be >= 0 (provided: %f)", alpha);
142 xbt_assert(cooling_efficiency >= 0 and cooling_efficiency <= 1,
143 ": cooling efficiency must be in [0,1] (provided: %f)", cooling_efficiency);
144 xbt_assert(max_power_w >= 0, ": maximal power must be >=0 (provided: %f)", max_power_w);
147 /** @ingroup plugin_chiller
148 * @param name The name of the Chiller.
149 * @param air_mass_kg The air mass of the room managed by the Chiller in kg (> 0).
150 * @param specific_heat_j_per_kg_per_c The specific heat of air in J per kg per °C (> 0).
151 * @param alpha The ratio of the other devices in the total heat dissipation (e.g. lighting, Power Distribution Unit)
153 * @param cooling_efficiency The cooling efficiency of the Chiller [0, 1].
154 * @param initial_temp_c The initial temperature of the room managed by the Chiller.
155 * @param goal_temp_c The goal temperature of the room. The Chiller is idle below this temperature.
156 * @param max_power_w The maximal power delivered by the Chiller in W (> 0). If this power is reached the room
157 * temperature will raise above the goal temperature.
158 * @return A ChillerPtr pointing to the new Chiller.
160 ChillerPtr Chiller::init(const std::string& name, double air_mass_kg, double specific_heat_j_per_kg_per_c, double alpha,
161 double cooling_efficiency, double initial_temp_c, double goal_temp_c, double max_power_w)
163 static bool plugin_inited = false;
164 if (not plugin_inited) {
166 plugin_inited = true;
168 auto chiller = ChillerPtr(new Chiller(name, air_mass_kg, specific_heat_j_per_kg_per_c, alpha, cooling_efficiency,
169 initial_temp_c, goal_temp_c, max_power_w));
170 chiller_model_->add_chiller(chiller);
174 /** @ingroup plugin_chiller
175 * @param name The new name of the Chiller.
176 * @return A ChillerPtr pointing to the modified Chiller.
178 ChillerPtr Chiller::set_name(std::string name)
180 simgrid::kernel::actor::simcall_answered([this, name] { name_ = name; });
184 /** @ingroup plugin_chiller
185 * @param air_mass_kg The new air mass of the Chiller in kg.
186 * @return A ChillerPtr pointing to the modified Chiller.
188 ChillerPtr Chiller::set_air_mass(double air_mass_kg)
190 xbt_assert(air_mass_kg > 0, ": air mass must be > 0 (provided: %f)", air_mass_kg);
191 simgrid::kernel::actor::simcall_answered([this, air_mass_kg] { air_mass_kg_ = air_mass_kg; });
195 /** @ingroup plugin_chiller
196 * @param specific_heat_j_per_kg_per_c The specific heat of the Chiller in J per kg per °C.
197 * @return A ChillerPtr pointing to the modified Chiller.
199 ChillerPtr Chiller::set_specific_heat(double specific_heat_j_per_kg_per_c)
201 xbt_assert(specific_heat_j_per_kg_per_c > 0, ": specific heat must be > 0 (provided: %f)",
202 specific_heat_j_per_kg_per_c);
203 simgrid::kernel::actor::simcall_answered(
204 [this, specific_heat_j_per_kg_per_c] { specific_heat_j_per_kg_per_c_ = specific_heat_j_per_kg_per_c; });
208 /** @ingroup plugin_chiller
209 * @param alpha The new alpha of the Chiller.
210 * @return A ChillerPtr pointing to the modified Chiller.
212 ChillerPtr Chiller::set_alpha(double alpha)
214 xbt_assert(alpha >= 0, ": alpha must be >= 0 (provided: %f)", alpha);
215 simgrid::kernel::actor::simcall_answered([this, alpha] { alpha_ = alpha; });
219 /** @ingroup plugin_chiller
220 * @param cooling_efficiency The new coolingefficiency of the Chiller.
221 * @return A ChillerPtr pointing to the modified Chiller.
223 ChillerPtr Chiller::set_cooling_efficiency(double cooling_efficiency)
225 xbt_assert(cooling_efficiency >= 0 and cooling_efficiency <= 1,
226 ": cooling efficiency must be in [0,1] (provided: %f)", cooling_efficiency);
227 simgrid::kernel::actor::simcall_answered([this, cooling_efficiency] { cooling_efficiency_ = cooling_efficiency; });
231 /** @ingroup plugin_chiller
232 * @param goal_temp_c The new goal temperature of the Chiller in °C.
233 * @return A ChillerPtr pointing to the modified Chiller.
235 ChillerPtr Chiller::set_goal_temp(double goal_temp_c)
237 simgrid::kernel::actor::simcall_answered([this, goal_temp_c] { goal_temp_c_ = goal_temp_c; });
241 /** @ingroup plugin_chiller
242 * @param max_power_w The new maximal power of the Chiller in W.
243 * @return A ChillerPtr pointing to the modified Chiller.
245 ChillerPtr Chiller::set_max_power(double max_power_w)
247 xbt_assert(max_power_w >= 0, ": maximal power must be >=0 (provided: %f)", max_power_w);
248 simgrid::kernel::actor::simcall_answered([this, max_power_w] { max_power_w_ = max_power_w; });
252 /** @ingroup plugin_chiller
253 * @param active The new active status of the Chiller.
254 * @return A ChillerPtr pointing to the modified Chiller.
256 ChillerPtr Chiller::set_active(bool active)
258 simgrid::kernel::actor::simcall_answered([this, active] { active_ = active; });
262 /** @ingroup plugin_chiller
263 * @param host The host to add to the room managed by the Chiller.
264 * @return A ChillerPtr pointing to the modified Chiller.
266 ChillerPtr Chiller::add_host(s4u::Host* host)
268 simgrid::kernel::actor::simcall_answered([this, host] { hosts_.insert(host); });
272 /** @ingroup plugin_chiller
273 * @param host The host to remove from the room managed by the Chiller.
274 * @return A ChillerPtr pointing to the modified Chiller.
276 ChillerPtr Chiller::remove_host(s4u::Host* host)
278 simgrid::kernel::actor::simcall_answered([this, host] { hosts_.erase(host); });
282 /** @ingroup plugin_chiller
283 * @return The time to reach to goal temp, assuming that the system remain in the same state.
285 double Chiller::get_time_to_goal_temp()
287 if (goal_temp_c_ == temp_in_c_)
290 double heat_power_w = 0;
291 for (auto const& host : hosts_)
292 heat_power_w += sg_host_get_current_consumption(host);
293 heat_power_w = heat_power_w * (1 + alpha_);
295 if (temp_in_c_ < goal_temp_c_)
296 return air_mass_kg_ * (goal_temp_c_ - temp_in_c_) * specific_heat_j_per_kg_per_c_ / heat_power_w;
301 return air_mass_kg_ * (temp_in_c_ - goal_temp_c_) * specific_heat_j_per_kg_per_c_ /
302 (power_w_ * cooling_efficiency_ - heat_power_w);
304 } // namespace simgrid::plugins