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Chuyển giao nhiệt và giảm áp suất của R-410A trong các ống nhôm đa cổng phẳng
Tóm tắt
Các bộ trao đổi nhiệt được hàn bằng nhôm có ống đa cổng phẳng đang được sử dụng làm bộ ngưng tụ cho điều hòa không khí dân dụng. Trong nghiên cứu này, các thử nghiệm ngưng tụ R-410A đã được thực hiện trong bốn ống đa cổng với đường kính thủy lực dao động từ 0.78 đến 0.95 mm. Phạm vi thử nghiệm bao gồm lưu lượng khối từ 100 đến 400 kg/m2 s và lưu lượng nhiệt ở mức 3 kW/m2, đây là các điều kiện vận hành điển hình của điều hòa không khí dân dụng. Kết quả cho thấy cả hệ số truyền nhiệt và sự sụt giảm áp suất đều tăng lên khi đường kính thủy lực giảm. Ảnh hưởng của đường kính thủy lực đến truyền nhiệt ngưng tụ lớn hơn rất nhiều so với các dự đoán từ các mối tương quan hiện có trong phạm vi điều tra. So sánh dữ liệu với các mối tương quan cho thấy một số mối tương quan của ống viễn thông và ống siêu viễn thông dự đoán hợp lý hệ số truyền nhiệt. Tuy nhiên, các mối tương quan của ống viễn thông đã dự đoán quá cao dữ liệu về sự sụt giảm áp suất.
Từ khóa
#ngưng tụ #truyền nhiệt #áp suất #ống đa cổng #R-410A #điều hòa không khíTài liệu tham khảo
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