System Specifications 1. Doppler phantom housing transverse dimension: 200mm × (80 ~ 100) mm Depth: 170mm. 2. Acoustic window size: 70um × 200mm × (80 ~ 100) mm 3. Ultrasound imitation organization (TM) material velocity: (1540 ± 10) m / s (23 ℃) Attenuation: standard set for (0.5 ± 0.05) dB / (cm · MHz) (23 ℃) (such as dedicated to the detection of the operating frequency At the high end or low end of the Doppler instrument, the choice of the attenuation coefficient is less than or greater than the value of TM material, especially made of imitation 4. ultrasound vascular density:. 0.930 (g / cm3) Material Velocity: 1555 (m / s) Material sound attenuation coefficient: frequency measurement varies with location, as shown in Table 1; diameter: standard sleeve for 8mm and 4mm, also in the range of 0.5 to 32mm chosen by a factor of two other dimensions, but pay special customized ; wall thickness: standard sleeve inside diameter of 8mm wall thickness of 1.6mm; 0.8mm internal diameter of the inner diameter of 4mm wall thickness change, thickness changed as shown in Table 2; the angle between the plane of the acoustic window: The standard set for 30 ° ( oblique section), but also the choice of 45 ° and 60 °, but pay special build. Table 1 imitation vascular sound attenuation material - Frequencies f (MHz) 2.0 3.5 4.0 5.0 7.5 8.0 α (dB / cm) 4.7 12 15 224 348 TABLE 2 imitation vessel diameter and wall thickness of the correspondence between the inner diameter (mm) 4 8 wall thickness (mm) 0.8 1.6 5. ultrasound imitation blood density: (1.03 ± 0.04) g / cm3 speed of sound: (1570 ± 30) m / s Attenuation: <0.1dB / (cm · MHz) backscatter: (1 ~ 10) × 10-9 × f4 / (cm · MHz4 · Sr) Viscosity: (4 ± 0.4) × 10-3Pa · s 6 Constant current pump revolutions: 0.2 ~ 300RMP Number of heads: 1 or 2 chucking silicone rubber hose: wall thickness of 1.5mm, the inner diameter of 0.8,1.6,3.1,4.8,6.4,7.9mm optional flow range: 0.014 ~ 1140ml / min control switch: left / stop / right speed control: adjustable potentiometer fluid via: only through pipes Power: Voltage 220 ± 10% AC, frequency 50 ~ 60Hz Working environment: Temperature 0 ~ 45 ℃, relative humidity <80% 7. Controller (optional) pulse parameter settings: width and interval were set minimum pulse width: 0.1s pulse minimum interval: 0.1s 8. meter rotor number: 2, used in tandem Range: 1 ~ 10L / h ( That 0.278ml / s ~ 2.78ml / s) 6 ~ 60L / h (ie 1. 67ml / s ~ 16.7ml / s) 9. fake blood tank capacity: 500ml; 10. buffer capacity:? 500ml;