Refrigeration apparatus, environment creating apparatus and refrigeration method
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing refrigeration apparatuses face challenges in energy saving, particularly due to the increased motive power of the compressor when injecting gas refrigerant into the medium pressure part of the compressor.
Innovation Solution
The refrigeration apparatus includes a main circuit with a compressor, condenser, subcooler, expansion mechanism, and evaporator, along with a first injection flow passage that allows the refrigerant to pass through the subcooler and be injected into the compressor midway through the compression process. This setup includes a first injection regulating valve controlled to achieve a target degree of superheat, adapting to varying refrigeration request degrees.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If gas refrigerant is injected into the medium pressure part of the compressor, then discharge pipe temperature is controlled, but motive power of the compressor increases
Solution Approach 1:
The patent changes the injection location from the medium pressure part to the low pressure suction port of the compressor, and adjusts the refrigerant state from gas to liquid form. These parameter changes allow temperature control while reducing the energy impact on the compressor
Solution Approach 2:
The patent introduces an intermediate cooling circuit as a mediator between the condenser and evaporator. This intermediate circuit with its expansion valve and cooling passage provides a separate pathway for refrigerant injection that cools the compressor without directly increasing its motive power requirements
2Temperature
If refrigerant is injected into the compressor to control temperature, then discharge pipe temperature is regulated, but energy consumption increases
Solution Approach 1:
The patent performs preliminary cooling by injecting liquid refrigerant into the low pressure suction port before compression occurs. This preliminary action reduces the temperature and pressure of the refrigerant entering the compressor, thereby reducing the compression work required and overall energy consumption
Solution Approach 2:
The patent extracts the temperature control function from the main compression process by creating a separate intermediate cooling circuit. This allows temperature regulation to occur independently through refrigerant injection into the suction port, separating the cooling function from the compression work
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration enhances energy saving by reducing the motive power of the compressor, particularly when the refrigeration request degree is low, while maintaining effective refrigerant injection and compression processes.
Implementation Method 1
a subcooler (12) disposed downstream of the condenser (2) in the main circuit
Implementation Method 2
an expansion mechanism (3) disposed downstream of the subcooler (12)
Implementation Method 3
an evaporator (4) disposed downstream of the expansion mechanism (3)
Implementation Method 4
a compressor (1) that compresses the refrigerant
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A refrigeration apparatus includes: a first injection flow passage branching off from a main circuit to allow a refrigerant to pass through a subcooler and be injected into a region of a compressor that is midway through a compression process; a first injection regulating valve disposed upstream of the subcooler in the first injection flow passage; a first valve control unit configured to control the first injection regulating valve such that a degree of superheat of the refrigerant injected through the first injection flow passage reaches a target degree of superheat; a reception unit configured to receive a refrigeration request degree; and a target superheat degree control unit configured to set the target degree of superheat to a first value when the refrigeration request degree received by the reception unit is a first refrigeration request degree and set the target degree of superheat to a second value higher than the first value when the received refrigeration request degree is a second refrigeration request degree lower than the first refrigeration request degree.