high heat absorbing Three-cavity solar vacuun tube

Structure

All-glass double-tube co-axial structure

Glass material

High borosilicate 3.3 glass

External pip diameter and thickness

Φ=47±1.0mm§=1.6mm±0.2mm

Φ=58±1.0mm§=1.8mm±0.2mm

Φ=70±1.5mm§=2.2mm±0.3mm

Internal pip diameter and thickness

Φ=37±0.8mm§=1.4mm±0.2mm

Φ=47±1.0mm§=1.6mm±0.2mm

Φ=58±1.0mm§=1.8mm±0.2mm

Pipe length

950mm 1500mm 1600mm 1700mm

1800mm 1900mm 2000mm 2100mm

Absorptive coating property

Structure

Cu/SS-ALN(H)/SS-ALN(L)/ALN

Sediment method

3 target magnetron sputtering plating

Specific absorption

As =0.93~0.96 (AM1.5)

Emission ratio

εh =0.04~0.06 (80±5)

Vacuum tightness

P≤5.0×10-3Pa

Idle sunning property parameters

Y=260~300 m2.C/KW

Solar irradiation for obtaining a preset water temperature

H≤4.7MJ/m2(Φ58)

H=3.7~4.2 MJ/m2

H≤3.7MJ/m2(Φ47)

H=2.9~3.2 MJ/m2

Average heat loss coefficient

ULT=0.4~0.6W/(m2.)