A Portable Pneumatic Driving Unit for a Left Ventricular Assist Device

1988 ◽  
Vol 11 (3) ◽  
pp. 186-190 ◽  
Author(s):  
N. Kabei ◽  
E. Shimemura ◽  
Y. Sakurai ◽  
K. Tsuchiya
Keyword(s):  
Flow Rate ◽  
Pressure Sensors ◽  
Left Ventricular ◽  
Pressure Level ◽  
Blood Pump ◽  
Ventricular Assist ◽  
Output Pressure ◽  
Output Flow ◽  
New Type ◽  
Output Characteristics

The authors developed a portable air driving unit for an artificial heart. As the portable energy source of the driver, a commercially available Ni-Cd battery was used. A linear compressor was selected as a portable size compressor. To reduce the number of parts to be assembled, a new type of pneumatic system was employed. In this system, the pressure level was regulated by varying the output flow rate of the compressor instead of using a pressure regulator and large air reservoirs. A one-board microcomputer and pressure sensors were used to control the pressure level. The total weight of the unit is 9.5 Kg. After assembling the components into the portable unit, a blood pump was connected to examine the output characteristics of the system. It was confirmed that the unit could drive the blood pump continuously for more than 2 hours under the following conditions: output flow rate of the blood pump = 5 L/min and output pressure — 100 mmHg.

Research on an axial-mounted dual magnetostrictive material rods-based electro-hydrostatic actuator

2021 ◽  
pp. 1045389X2110145
Author(s):  
Yuchuan Zhu ◽  
Chang Liu ◽  
Yunze Song ◽  
Long Chen ◽  
Yulei Jiang ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Flow Rate ◽  
Flow Distribution ◽  
Maximum Flow ◽  
Magnetostrictive Material ◽  
Simulation Techniques ◽  
Motion State ◽  
New Type ◽  
Output Characteristics ◽  
Active Rectification

In this paper, an electro-hydrostatic actuator driven by dual axial-mounted magnetostrictive material rods-based pumps (MMPs) with a new type of active rectification valve is designed in the current study. Based on flow distribution of the active rectification valve and driving energy provided by two MMPs, the actuator can output continuous and bidirectional displacement. By establishing a mathematical model of the actuating system, using simulation techniques, the change rule of hydraulic cylinder’s motion state caused by different driving signals are studied and analyzed. Test equipment platform is constructed in the laboratory to test the output characteristics and confirm the feasibility of the new concept. The experimental results indicate that the maximum flow rate can reach approximately 2.7 L·min−1, while the operating frequency is 180 Hz.

Impact of Washout Blades in a Multiple Disk Centrifugal Blood Pump

1999 ◽  
Author(s):  
Michelle J. Holmes ◽  
Gerald E. Miller
Keyword(s):  
Blood Flow ◽  
Flow Patterns ◽  
Blood Pump ◽  
Ventricular Assist ◽  
Centrifugal Blood Pump ◽  
Bridge To Transplant ◽  
Rotation Rates ◽  
Parallel Configuration ◽  
Output Characteristics ◽  
Blood Flow Patterns

Abstract A multiple disk, centrifugal blood pump (MDCP) for use as a ventricular assist device or as a bridge to transplant device has previously been designed and its output characteristics have been analyzed (Miller et al. 1990, 1993). The propelling mechanism of this device consists of six multiple disks assembled in a parallel configuration. Upon rotation these disks create centrifugal and shearing forces, which work to propel the fluid. This pump operates at lower rotation rates than other rotary blood pumps. The lower rotation rates reduce the chance for hemolysis, but may promote thrombosis formation due to stagnant blood flow. Previous flow visualization studies conducted by Miller et al. (1995) analyzed the blood flow patterns within the device. Results of this study indicated a region of flow stagnation between the last solid disk and the housing. In this investigation, further studies were performed that verified this recirculation. To provide washout of this region, eight, small Lexan blades were attached to the back of the last disk. Reevaluation of the flow patterns, following the blade attachment, revealed that the addition of the blades was successful in producing washout, thus reducing the possibility of thrombosis formation.

Design and Numerical Evaluation of an Axial Partial-assist Blood Pump for Chinese and other Heart Failure Patients

2017 ◽  
Vol 40 (9) ◽  
pp. 489-497 ◽  
Author(s):  
Guang-Mao Liu ◽  
Dong-Hai Jin ◽  
Jian-Ye Zhou ◽  
Xi-Hang Jiang ◽  
Han-Song Sun ◽  
...  
Keyword(s):  
Heart Failure ◽  
Shear Stress ◽  
Flow Rate ◽  
Tangential Velocity ◽  
Pressure Head ◽  
Left Ventricular ◽  
Blood Pump ◽  
Partial Support ◽  
Heart Failure Patients ◽  
Cantilever Structure

A fully implantable axial left ventricular assist device LAP31 was developed for Chinese or other heart failure patients who need partial support. Based on the 5-Lpm total cardiac blood output of Chinese without heart failure disease, the design point of LAP31 was set to a flow rate of 3 Lpm with 100-mmHg pressure head. To achieve the required pressure head and good hemolytic performance, a structure that includes a spindly rotor hub and a diffuser with splitter and cantilevered main blades was developed. Computational fluid dynamics (CFD) was used to analyze the hydraulic and hemodynamic performance of LAP31. Then in vitro hydraulics experiments were conducted. The numerical simulation results show that LAP31 could generate a 1 to 8 Lpm flow rate with a 60.9 to 182.7 mmHg pressure head when the pump was rotating between 9,000 and 12,000 rpm. The average scalar shear stress of the blood pump was 21.7 Pa, and the average exposure time was 71.0 milliseconds. The mean hemolysis index of LAP31 obtained using Heuser's hemolysis model and Giersiepen's model was 0.220% and 3.89 × 105% respectively. After adding the splitter blades, the flow separation at the suction surface of the diffuser was reduced. The cantilever structure reduced the tangential velocity from 6.1 to 4.7–1.4 m/s within the blade gap by changing the blade gap from shroud to hub. Subsequently, the blood damage caused by shear stress was reduced. In conclusion, the hydraulic and hemolytic characteristics of the LAP31 are acceptable for partial support.

Experimental Testing of a New Left Ventricular Assist Device???The Microdiagonal Blood Pump

ASAIO Journal ◽  
2004 ◽  
Vol 50 (3) ◽  
pp. 200-204 ◽  
Author(s):  
STEFAN CHRISTIANSEN ◽  
L??TF?? DEMIRCAN ◽  
PAUL B. KWANT ◽  
MUSTAFA AKDIS ◽  
STEFFEN REX ◽  
...  
Keyword(s):  
Left Ventricular Assist Device ◽  
Ventricular Assist Device ◽  
Experimental Testing ◽  
New Left ◽  
Left Ventricular ◽  
Blood Pump ◽  
Assist Device ◽  
Ventricular Assist ◽  
Left Ventricular Assist
Sign in / Sign up

Export Citation Format

Share Document