Got it ✅ You want to simulate a modified ZECC for onion storage using the data you already wrote (charcoal, ventilation, humidity control, etc.). For simulation, the key is to translate the physical design and working principle into a model description (inputs, processes, outputs).
Here’s a clear structured description for simulating the onion ZECC model:
---
🔹 Simulation Model for ZECC Adapted for Onions
1. Objective
To simulate a Zero Energy Cool Chamber (ZECC) adapted for onion storage using charcoal as the primary medium, ensuring cooling without excess humidity.
---
2. Inputs / Variables
Ambient Temperature (Ta): Outside air temperature (°C).
Ambient Relative Humidity (RHₐ): Outside humidity (%).
Water Input (W): Amount of water added to charcoal per day (liters).
Ventilation Rate (V): Airflow inside chamber (m³/hr).
Charcoal Moisture Content (Cm): Percentage of water retained in charcoal (%).
Onion Respiration Rate (Or): Heat and moisture released by onions (kJ/hr & g H₂O/hr).
Storage Load (S): Weight of onions stored (kg).
---
3. Processes
Evaporative Cooling:
Evaporation of water from charcoal absorbs heat, lowering internal chamber temperature.
Cooling Efficiency (η) = f(W, Cm, Ta, RHₐ).
Humidity Regulation:
Charcoal absorbs moisture, moderating RH.
Excess water input → high RH → onion spoilage.
Ventilation reduces RH and removes onion respiration moisture.
Heat & Moisture Balance:
Heat Balance:
Tchamber = Ta - (η × Cooling Potential)
Moisture Balance:
RHchamber = function(W, Cm, V, Or)
---
4. Outputs
Chamber Temperature (Tc): Simulated internal temperature.
Chamber Humidity (RHc): Internal relative humidity (%).
Onion Shelf Life (Ls): Estimated based on Tc and RHc using spoilage model.
Lower Tc = reduced sprouting.
RH < 65% = reduced fungal growth.
---
5. Simulation Flow (Step-by-Step)
1. Input ambient climate conditions (Ta, RHₐ).
2. Set water input (W) for charcoal layer.
3. Calculate cooling efficiency (η) and predict chamber temperature drop.
4. Compute RH inside chamber considering charcoal absorption + ventilation + onion respiration.
5. Check thresholds:
Tc target: 25–28 °C (for Indian conditions).
RH target: 60–65%.
6. Estimate onion storage life (Ls) using spoilage index based on fungal risk & sprouting probability.
7. Adjust variables (W, V, Cm) in simulation to optimize results.
---
6. Simulation Environment Options
Simple Spreadsheet Model: Use Excel with formulas for Tc and RH.
Software Simulation: MATLAB / Simulink, ANSYS Fluent (for airflow & heat transfer), or COMSOL (moisture diffusion).
IoT Sensor Prototype: Use DHT11/22 (temp & humidity sensors) + Arduino to monitor real ZECC prototype and compare with simulation results.
---
👉 In short: the simulation is about dynamically balancing temperature & humidity inside a charcoal-based ZECC, ensuring conditions remain within the safe zone for onions.
---
Would you like me to design this simulation as an Excel-based model (step formulas + graphs) for easier demonstration, or as a flow diagram showing the system’s working cycle?
