
solar vacuum tubeVACUUM TUBE
| MODEL ITEMS |
GB(single target) | SG(three target) | ||
| Configuration | Double-layer concentric boronsillicate glass tubes | Double-layer concentric boronsillicate glass tubes | ||
| Glass thermal expansion coefficient | 3.3*10-6/℃ | 3.3*10-6/℃ | 3.3*10-6/℃ | 3.3*10-6/℃ |
| Diameter of outer tube | φ47±1mm | φ58±1mm | Φ47±1mm | Φ58±1mm |
| Diameter of absorber tube | φ37±1mm | φ47±1mm | Φ37±1mm | Φ47±1mm |
| Thickness | 1.5mm(±0.15mm) | 1.6mm(±0.15mm) | 1.5mm(±0.15mm) | 1.6mm(±0.15mm) |
| Transmittance of outer tube | 0.91 | 0.91 | 0.91 | 0.91 |
| Length | 1500±5mm | 1800±5mm | 1500±5mm | 1800±5mm |
| Solar selective absorbing coating | Al-N/Al | Al-N/Al | AIN/AIN-SS/Cu | AIN/AIN-SS/Cu |
| Absorptance(AM1.5) | ≥0.89 | ≥0.89 | ≥0.92 | ≥0.92 |
| Emittance | ≤0.08(80℃) | ≤0.08(80℃) | ≤0.07(80℃) | ≤0.07(80℃) |
| Vacuum | P≤5*10-3Pa | P≤5*10-3Pa | P≤5*10-3Pa | P≤5*10-3Pa |
| Stagnation parameter | ≥230㎡℃/KW | ≥230㎡℃/KW | ≥270㎡℃/KW | ≥270㎡℃/KW |
| Average Heat loss coefficient | ≤0.85W/(㎡*℃) | ≤0.85W/(㎡*℃) | ≤0.7W/(㎡*℃) | ≤0.7W/(㎡*℃) |
| Solar irradiation under stagnation | ≤3.5MJ/㎡ | ≤3.5MJ/㎡ | ≤3.2MJ/㎡ | ≤3.2MJ/㎡ |
| Hailstone resistance | hailstone diameterФ25mm | hailstone diameterФ25mm | hailstone diameterФ25mm | hailstone diameterФ25mm |
| Pressure-endure ability | 0.6mPa | 0.6mPa | 0.6mPa | 0.6mPa |