scholarly journals Flow Characteristic and Trapping Characteristics of Cycloid Rotor Pump

2015 ◽  
Vol 9 (1) ◽  
pp. 449-454 ◽  
Author(s):  
Ren Zhenxing ◽  
Liu Chunyan ◽  
Li Yulong
Keyword(s):  
Flow Rate ◽  
Flow Characteristics ◽  
Position Angle ◽  
Gear Pump ◽  
Rotary Pump ◽  
Uniformity Coefficient ◽  
Discharge Pressure ◽  
Instantaneous Flow Rate ◽  
External Gear Pump ◽  
Better Than

To accurately calculate the flow rate of cycloid rotary pump as well as to correctly understand its trapped oil phenomenon, firstly the instantaneous flow rate formula of cycloid rotary pump was established based on the method of swept area, and then it was compared with the two present approximate formulas by an example. Secondly, based on the established flow rate formula and the created trapped oil model in the present literature, the trapped oil pressure of a single cavity near the minimum volume position was simulated. It was pointed that for cycloid rotary pump as an example, the flow non-uniform coefficient was 6.45%, and in contrast, the flow non-uniformity coefficient of external gear pump was 21.2%. Relative to the accurate results, the two present approximate errors of flow rates were 1.93% and 2.90%; and the present approximate error of flow non-uniform coefficient was 7.13%; when the minimum position angle was added by 0.5° or 1° or 2°, relative to discharge pressure of the pump, the corresponding maximum peak of trapped oil pressure increased by 1.6% or 6.0% or 21.7%. The results indicate that the flow characteristics of cycloid rotary pump are better than the external gear pump, the two present approximate errors of flow rate are little but the present approximate error of flow non-uniform coefficient is higher. Also, there is a trapped oil phenomenon in cycloid rotary pump which is not obvious.

Experimental Investigation of Flowrate Irregularity in Rotary Gear Pumps

1992 ◽  
Author(s):  
G. Mimmi
Keyword(s):  
Experimental Investigation ◽  
Flow Rate ◽  
Experimental Tests ◽  
Periodic Variation ◽  
Experimental Results ◽  
Gear Pump ◽  
Gear Pumps ◽  
Hot Film ◽  
Instantaneous Flow Rate ◽  
External Gear Pump

Abstract In a previous paper the author proposed a method to reduce the periodic variation in flow rate for an external gear pump. To verify the experimental results, a series of experimental tests on a expressly realized gear pump, was carried out. The pump was equipped with relieving grooves milled into the side plates. The tests were done on a closed piping specifically realized and equipped for measuring the instantaneous flow rate of the fluid through a wedge-shaped hot film probe.

Principle and structure of a printed circuit board process–based piezoelectric microfluidic pump integrated into printed circuit board

2019 ◽  
Vol 30 (17) ◽  
pp. 2595-2604 ◽  
Author(s):  
Dai-Hua Wang ◽  
Lian-Kai Tang ◽  
Yun-Hao Peng ◽  
Huai-Qiang Yu
Keyword(s):  
Flow Rate ◽  
Printed Circuit Board ◽  
Flow Characteristics ◽  
Circuit Board ◽  
Microfluidic Systems ◽  
Printed Circuit ◽  
Board Processes ◽  
Voltage Frequency ◽  
Instantaneous Flow Rate ◽  
Board Process

Considering mature printed circuit board processes, researches on microfluidic pumps that can be integrated into printed circuit board will provide a solution for further miniaturization and integration of microfluidic systems with low costs. The principle and structure of a printed circuit board process–based piezoelectric microfluidic pump integrated into printed circuit board are proposed and realized in this article. The printed circuit board process–based design and manufacturing technology of a piezoelectric microfluidic pump integrated into printed circuit board is researched utilizing printed circuit board as a platform. The flow characteristics of the fabricated microfluidic pump are experimentally tested. The research results show that the proposed principle and structure of the piezoelectric microfluidic pump can be fabricated utilizing mature printed circuit board process with advantages of simple structure and convenient processing. The fabricated printed circuit board process–based microfluidic pump can linearly pump in and pump out fluid with self-injection. Moreover, the flow rate and back pressure can be controlled by changing the peak-to-peak value, frequency, and phase difference of the driving voltages. The instantaneous flow rate has the pulsation property consistent with the drive voltage frequency. The proposed principle and structure are beneficial to integrate the fabricated printed circuit board process–based microfluidic pump with other microfluidic components to realize complicated microfluidic systems on printed circuit board.

scholarly journals Effects of operation conditions and suction pipeline parameters on flow characteristics and metering accuracy for selective catalytic reduction air-assisted urea dosing system

2019 ◽  
Vol 103 (1) ◽  
pp. 003685041987419
Author(s):  
Shudong Yang ◽  
Xiwei Pan ◽  
Youcheng Shi ◽  
Yinshui Liu
Keyword(s):  
Mathematical Model ◽  
Selective Catalytic Reduction ◽  
Flow Rate ◽  
Catalytic Reduction ◽  
Flow Characteristics ◽  
Flow Stability ◽  
Oxides Of Nitrogen ◽  
Pump Speed ◽  
Operation Conditions ◽  
Discharge Pressure

Selective catalytic reduction is the main technology to reduce oxides of nitrogen of diesel exhaust. As an important part of the selective catalytic reduction system, the air-assisted urea dosing system regulates the flow rate by adjusting the pump speed, and the flow rate and its metering accuracy directly affect the efficiency of oxides of nitrogen conversion. A mathematical model coupled with the air-assisted urea dosing system and the suction pipeline was built, and the influences of the discharge pressure, pump speed, suction pipeline length, and diameter on the flow characteristics and metering accuracy of the air-assisted urea dosing system were analyzed. The flow rate and metering accuracy of a prototype of the air-assisted urea dosing system were tested under different conditions on a test rig. Results show that the flow stability and metering accuracy of the prototype elevate with increasing the discharge pressure when the prototype has no overfeeding, and it gets down under any discharge pressure when the prototype occurs overfeeding. The flow stability and metering accuracy of the prototype improve with increasing the pump speed, and increase significantly when the suction pipeline length becomes shorter and the diameter gets larger. The metering accuracy of the prototype can achieve to ±2% by optimizing the suction pipeline parameters. The experimental results prove that the proposed mathematical model is effective.

Theoretical Analysis and Design of a Variable Delivery External Gear Pump for Low and Medium Pressure Applications

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Srinath Tankasala ◽  
Andrea Vacca
Keyword(s):  
High Pressures ◽  
Optimization Approach ◽  
Gear Pump ◽  
Flow Variation ◽  
Analysis And Design ◽  
Target Pressure ◽  
Electric Actuation ◽  
Variation Mechanism ◽  
Instantaneous Flow Rate ◽  
External Gear Pump

This paper describes a unique design concept that is capable of electronically controlling the flow delivered by an external gear pump (EGP). The principle used for varying the flow relies on the variable timing concept which has been previously demonstrated by the author's research team for EGP's operating at high pressures (HPs) (p > 100 bar). This principle permits to vary the flow within a certain range, without introducing additional sources of power loss. In this paper, the above concept has been applied to formulate a design for a variable delivery EGP for low pressure (LP) applications (p < 30 bar), suitable for direct electric actuation. Specific design principles for the gear and the flow variation mechanisms are introduced to limit the force required by the electric actuation, and for maximizing the flow variation range. Also, the low target pressure allows the variable timing principle to be realized with an asymmetric solution, with only one variable timing element present at one side of the gears. A detailed analysis concerning the relationship between the electrically commanded position of the flow varying element and the theoretical flow delivered by the pump is also presented. This analysis is used to formulate analytical expressions for the instantaneous flow rate and the flow nonuniformity of the pump. The paper details the design principle of the proposed variable flow pump and describes the multi-objective optimization approach used for sizing the gears and flow variation mechanism. The paper also discusses the experimental activity performed on a prototype of the proposed unit, able to achieve a flow variation of 31%.

Three-dimensional model of an external gear pump with an experimental evaluation of the flow ripple

2020 ◽  
pp. 095440622093704 ◽  
Author(s):  
Alessandro Corvaglia ◽  
Alessandro Ferrari ◽  
Massimo Rundo ◽  
Oscar Vento
Keyword(s):  
Flow Rate ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Gear Pump ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Flow Meter ◽  
Flow Ripple ◽  
Delivery Pressure ◽  
External Gear Pump

A three-dimensional model of an external gear pump and a new application of an algorithm for the measurement of the unsteady flow rate in hydraulic pipes are presented. The experimental delivery flow ripple was compared with the outcomes of a simulation under different operating conditions. A comprehensive computational fluid dynamics model of the pump and of the high-pressure delivery circuit was developed in SimericsMP+®. The pump model considers the clearances, which vary according to the shaft angle, between the tip of the tooth and the inner surface of the stator, as well as between the flanks of the teeth that are in contact. The pump delivery circuit is constituted by a straight pipe with a fixed orifice at the end to generate the load. The model of the entire system was preliminarily validated in terms of delivery pressure ripple. Subsequently, the simulated flow ripple was contrasted with the instantaneous flow rate, measured by means of an innovative flow meter. It was found that the proposed flow meter is reliable in assessing the flow oscillations under the various working conditions.

scholarly journals Comparative Study on Flow Characteristics of Pipeline System Based on CFD

2021 ◽  
Vol 252 ◽  
pp. 02053
Author(s):  
Hou Yingzhe ◽  
Wu Hao ◽  
Yan Xiaozhe ◽  
Zhu Haoqiang ◽  
Gao Haitao ◽  
...  
Keyword(s):  
Flow Field ◽  
Flow Rate ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Simulation Method ◽  
Hot Water ◽  
Pipeline System ◽  
Uniformity Coefficient ◽  
Study Results ◽  
Pipeline Vibration

Based on the CFD numerical simulation method, this paper established a pipeline model to study the internal flow characteristics of three different combinations of hot water pipeline systems and thus obtained the flow field information such as pressure, flow rate, and flow rate inside the pipeline. The study results showed that the smoother the pipeline transition, the smaller the velocity uniformity coefficient; the higher the uniformity of the flow field, the smaller the pressure and velocity fluctuations, the smaller the resulting pipeline vibration. Besides, the flow characteristics have been greatly improved.

Sign in / Sign up

Export Citation Format

Share Document