Basic Design Principles
1. Usage requirements and operating conditions
2. Ensuring stability within a certain operating range
3. Optimization of performance and economic indicators
General Design Steps
1. Determining the type and structure of the system
2. Determining the design operating conditions and load
3. Determining the performance, form, and size of each component of the refrigeration system
4. Verification under non-design operating conditions
Heat Gain and Cooling Load
Heat gain: The amount of heat entering the building (or cold room)
Cooling load: The amount of heat that needs to be removed to maintain the environment (indoor or cold room air temperature) at the required value.
The cooling load is generally not constant. The design load for air conditioning/cold storage generally refers to the maximum cooling load.
Heat Gain in Cold Storage
1. Heat transfer through the enclosure: including glass
2. Heat from goods (cooling, freezing, cold processing)
3. Heat from air exchange (air replacement)
4. Operational heat (heat generated by personnel operation, various equipment, and air ingress from opening doors)
