Calculating the heat load for a hot water boiler essentially involves matching the appropriate formulas and parameters based on your specific application (e.g., heating, domestic hot water, or industrial heat use). Let me outline the key steps and points for you.
Core Calculation Formula
The basic calculation formula for heat load (unit: kW) is:
Q = c × m × ΔT
Where:
Q: Required heat load (kW)
c: Specific heat capacity of water (approximately 4.186 kJ/(kg·℃))
m: Mass flow rate of water (kg/h)
ΔT: Supply and return water temperature difference (℃)
Calculation by Purpose
Heating Purpose
Simplified Formula:
S: Heating area (㎡)
q: Heat index per unit area (W/㎡, selected according to building type and insulation level)
ΔT: Indoor and outdoor temperature difference (℃)
Key Parameters:
Heat index per unit area (q): Approximately 40-60 W/㎡ for ordinary residential buildings, and up to 80-120 W/㎡ for shopping malls/factories.
Temperature difference (ΔT): Determined based on the local minimum winter temperature and the set indoor temperature. Domestic Hot Water Uses
Formula: Q = c × m × ΔT
m: Daily average hot water consumption (kg/h)
ΔT: Water temperature rise (°C)
Key Parameters:
Hot water consumption: Estimated based on the number of people, e.g., 50-100L per person per day.
Temperature rise: Typically heating from 10°C to 55°C, ΔT≈45°C.
Industrial Uses
The heat demand for each stage of the production process needs to be calculated, considering temperature, pressure, and the heat capacity of the substances.
