Client: Hitachi Air Conditioning
Client Requirements
As a leading enterprise in the air conditioning industry, Hitachi Air Conditioning is committed to developing highly efficient and energy-saving central air conditioning and other products. During the research and development process of one of its new products, it is necessary to conduct precise measurement of the external flow field characteristics of its air conditioning fan. The specific requirements are as follows:1. Five-hole probe low-speed calibration: Ensure measurement accuracy in low-speed airflow environments (such as air conditioning supply scenarios).
2. Speed and Angle measurement: The speed measurement error should be less than 2%, and the Angle coverage range should be greater than ±30° to meet the multi-dimensional analysis requirements under complex airflow conditions.
3. Pressure measurement: The pressure resolution should be less than 1% to precisely capture the minute pressure fluctuations within the air ducts of the air conditioning system.
4. Three-dimensional velocity field and pressure field measurement: Comprehensively obtain the three-dimensional distribution data of the fan's external flow field to provide a basis for optimizing air duct design and reducing energy consumption.
Products Applied
Five-hole probe: Utilizing high-precision calibration technology, it supports multi-parameter measurement in low-speed environments.Intelligent pressure scanning valve: Multi-channel pressure acquisition system, real-time collection of pressure data.
Electric displacement mechanism + motion controller: Fully automatic three-dimensional positioning system, achieving precise measurement of spatial points in the flow field.
Case Details
In the process of developing new products, Hitachi Air conditioners need to optimize the airflow path, improve energy efficiency and reduce noise. To achieve this goal, a systematic test of the external flow field of the air conditioning fan is required:1. Low-speed calibration and flow field calibration:
In the low-speed wind tunnel, a five-hole detector is used for calibration to ensure that the error meets the experimental requirements. The static pressure and dynamic pressure data are collected in real time through the pressure scanning valve. Combined with the electric displacement mechanism, the three-dimensional flow field scanning is completed, covering the multi-angle distribution of the fan in the axial, radial and tangential directions.
2. Simulation and Verification of Complex Working Conditions
Simulate the extreme working conditions in the actual operation of the air conditioner to verify the flow field stability of the fan at different rotational speeds. Analyze abnormal phenomena such as airflow separation and vortices, and optimize the blade design to reduce energy loss.
3. Data-driven Design Optimization:
Combining Hitachi Air conditioning's digital modeling capabilities, the measured data is compared with the simulation model to correct the product design parameters, thereby enhancing the product performance.
Experimental Results
1. Precision compliance: The speed measurement error is controlled within 0.05%, and both the Angle coverage and pressure resolution meet the requirements of the experimental design.2. Energy efficiency improvement: The optimized fan design enhances the overall energy efficiency of the machine, reaching international leading standards.
3. Noise reduction and enhanced reliability: Through flow field optimization, the peak vibration of the fan is reduced, supporting the stable operation of the air conditioner under high-temperature conditions.
4. Enhanced R&D efficiency: Through the full-process service of the entire set of flow field measurement and control equipment, the measurement and testing cycle has been shortened, and product iteration has been accelerated.
