Pulsation Energy in the Suction Manifold of a Reciprocating Compressor as a Measure for Parameter Sensitivity

2015 ◽  
Vol 137 (2) ◽  
Author(s):  
Nasir Bilal ◽  
Douglas E. Adams
Keyword(s):  
Design Parameter ◽  
Critical Parameter ◽  
Design Parameters ◽  
Reciprocating Compressor ◽  
Input Design ◽  
Parameter Variations ◽  
Pulsation Model ◽  
Unique Method ◽  
Parameter Values ◽  
Gas Pulsations

Gas pulsations in a compressor suction manifold radiate noise and reduce the efficiency of the compressor. The objective of this paper is to identify and quantify the effects of modeling assumptions and uncertainties in input parameters on the pulsation model output predictions and to estimate the sensitivity of the model to changes in the input design parameters. A unique method of sensitivity analysis is presented that uses the total pulsation energy in the suction manifold of a compressor as a measure of gas pulsations. This method is used to determine the sensitivity of the gas pulsations in the suction manifold to input design parameters. First, the gas pulsations in the suction manifold are calculated using linear acoustic theory. Second, the effects of varying several different design parameters of the suction manifold on gas pulsations are analyzed, and the three most important parameters are selected. Next, energy due to gas pulsations in the suction manifold due to these design parameter variations is calculated. Suction manifold radius was identified as the most critical parameter, followed by width and depth. The optimized values of manifold radius resulted in an overall reduction of up to 24% in the gas pulsation energy compared to the pulsation energy at the nominal design parameter values in the suction manifold.

An Efficient Design Procedure for MEMS Electrothermal Microgripper

2021 ◽  
pp. 1-6
Author(s):  
Ananya Roy ◽  
Rajasree Sarkar ◽  
Arunava Banerjee ◽  
M Nabi
Keyword(s):  
Design Parameter ◽  
Low Voltage ◽  
Design Procedure ◽  
Design Parameters ◽  
Optimized Design ◽  
Efficient Design ◽  
The Finite Element Method ◽  
Compact Size ◽  
Sine Cosine Algorithm ◽  
Parameter Values

Abstract With the development of miniaturization technology, MEMS electrothermal microgrippers have been widely used owing to their compact size, ease of manufacturing, and low production cost. Since most of these systems are governed by partial differential equations (PDEs), modeling of microgrippers poses a significant challenge for designers. To reduce the overall computational complexity, it is a common practice to model the microgripper system using the finite element method (FEM). During the design process, the geometric and analytical properties of the microgripper influence the system dynamics to a great extent, and this work focuses on studying the effects of such parameter changes. In low voltage applications, the performance of the microgripper is influenced by the geometrical variations, and the air gap. Hence, for the modeling of the microgripper, actuator arm lengths, and the gap between the arms are chosen as the two main geometric design parameters, while the input current density is considered as the analytical design parameter. In this work, the optimized design parameter values for maximum possible displacement are obtained with the use of Sine Cosine Algorithm (SCA). Further, an averaging operation is proposed for efficiently designing the MEMS electrothermal microgripper, and the efficacy of the proposed design methodology is demonstrated through simulation studies.

Influence of Design Parameter Variations for Propeller-Boss-Cap-Fins on Hub Vortex Reduction

2016 ◽  
Vol 60 (04) ◽  
pp. 203-218
Author(s):  
Jeonghwa Seo ◽  
Seung-Jae Lee ◽  
Bumwoo Han ◽  
Shin Hyung Rhee
Keyword(s):  
Pitch Angle ◽  
Design Parameter ◽  
Open Water ◽  
Chord Length ◽  
Stereoscopic Particle Image Velocimetry ◽  
Design Parameters ◽  
Phase Lag ◽  
Water Efficiency ◽  
Parameter Variations ◽  
Wake Fields

The present study aimed to identify significant design parameters on the propeller open water efficiency and characteristics of the wake field of a propeller with propeller-boss-cap-fins (PBCFs), with special attention to hub vortex dynamics. A towed underwater stereoscopic particle image velocimetry system was used to measure the near wake fields of a five-bladed propeller and a PBCF model. Through model tests, it was confirmed that the disappearance of a low-pressure area behind a boss cap, i.e., a reduction of the hub vortex, was the dominant contribution to open water efficiency gains from PBCF rather than a decrease in net torque. Global force and wake fields were also measured in response to design parameter variations of PBCF, i.e., fin chord length, fin span height, pitch angle, and phase lag. In the cases of pitch angle and fin chord length variations, PBCF with a light loading configuration had better open water efficiency than the baseline PBCF. However, in the case of a short fin span height for light loading configuration, the hub vortex was not entirely prevented, and the total open water efficiency decreased. Under heavy loading configurations, excessive negative and torque degraded the open water efficiency. Phase lag variations were less effective with respect to the open water efficiency than other design parameter variations.

Analysis of a Tubular Linear Permanent Magnet Motor for Reciprocating Compressor Applications

2013 ◽  
Vol 448-453 ◽  
pp. 2114-2119 ◽  
Author(s):  
Izzeldin Idris Abdalla ◽  
Taib Ibrahim ◽  
Nursyarizal Mohd Nor
Keyword(s):  
Permanent Magnet ◽  
Permanent Magnets ◽  
Outer Radius ◽  
Design Parameters ◽  
Reciprocating Compressor ◽  
Permanent Magnet Motors ◽  
Permanent Magnet Motor ◽  
Element Analysis ◽  
Split Ratio ◽  
Single Coil

This paper describes a design optimization to achieve optimal performance of a two novel single-phase short-stroke tubular linear permanent magnet motors (TLPMMs) with rectangular and trapezoidal permanent magnets (PMs) structures. The motors equipped with a quasi-Halbach magnetized moving-magnet armature and slotted stator with a single-slot carrying a single coil. The motors have been developed for reciprocating compressor applications such as household refrigerators. It is observed that the TLPMM efficiency can be optimized with respect to the leading design parameters (dimensional ratios). Furthermore, the influence of mover back iron is investigated and the loss of the motor is computed. Finite element analysis (FEA) is employed for the optimization, and the optimal values of the ratio of the axial length of the radially magnetized magnets to the pole pitch as well as the ratio of the PMs outer radius-to-stator outer radius (split ratio), are identified.

Influence of Design Parameter Variations for Propeller-Boss-Cap-Fins on Hub Vortex Reduction

2016 ◽  
Vol 60 (4) ◽  
pp. 203-218 ◽  
Author(s):  
Jeonghwa Seo ◽  
Seung Jae Lee ◽  
Bumwoo Han ◽  
Shin Hyung Rhee
Keyword(s):  
Design Parameter ◽  
Parameter Variations

Semi-controlled experiment plans for improved mechanical engineering designs

2000 ◽  
Vol 214 (2) ◽  
pp. 95-105 ◽  
Author(s):  
C J Sexton ◽  
W Dunsmore ◽  
S M Lewis ◽  
C P Please ◽  
G Pitts
Keyword(s):  
Response Surface ◽  
Special Interest ◽  
Design Parameter ◽  
Orthogonal Arrays ◽  
Small Sample ◽  
Design Parameters ◽  
Hydraulic Pump ◽  
Parameter Region ◽  
Mechanical Products ◽  
Engineering Designs

The use of planned experiments to improve designs is considered for situations where standard plans, such as orthogonal arrays or response surface plans, are impractical. An approach is described that is of special interest to the design of mechanical products where it is expensive to make prototype components to specified dimensions, and only a given small sample of components of diffiering dimensions is available. The plan for the experiment must then make the best use of the available components by determining an assembly that will most efficiently explore the expected design parameter region where the design parameters may be derived from the component dimensions. In contrast to conventional methods, the resulting experiment is semi-controlled, rather than fully controlled, as the component dimensions cannot be chosen but the assembly can. An algorithm for finding such plans is described and an example of its implementation in improving the design of an hydraulic pump is presented. The method extends to studies involving some components whose dimensions cannot be designated and hence are obtained from a small sample, and other components that are easily and cheaply constructed to prescribed dimensions. This results in a combination of semi-controlled and fully controlled factors. Efficient plans for such experiments are described and results from their application in practice are discussed.

scholarly journals Optimization of Design Parameters of Spiral Spring for Active Headrest Deployment

2018 ◽  
Vol 167 ◽  
pp. 02017
Author(s):  
Yunsik Yang ◽  
Euy Sik Jeon ◽  
Dae Ho Park
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Optimal Design ◽  
Relative Motion ◽  
Design Parameter ◽  
Development Time ◽  
Design Parameters ◽  
Element Analysis ◽  
Spiral Spring ◽  
The Finite Element Analysis

Several studies have been conducted to prevent neck injury in rear-end collision. The headrest of the seat which suppresses the relative motion of the head and the torso can suppress the extension of the head, thereby alleviating the injury. The active headrest has a mechanism that supports the head by deploying the headrest at the rear-end collision. The spring remains compressed or twisted until a collision signal is generated and the headrest is deployed after the collision signal. Depending on the shape and deployment structure of the spring, a spring design with a high resilience that is acceptable to the headrest is required. In this paper, design parameter of spiral spring suitable for the structure of the developed headrest is selected, prototypes are fabricated, and development parameters such as development time and development distance are checked and optimal design parameters of the spiral spring are derived. The feasibility of the headrest with the designed spiral spring was verified by the finite element analysis.

scholarly journals A Globally Optimal Robust Design Method for Complex Systems

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-25
Author(s):  
Yue Chen ◽  
Jian Shi ◽  
Xiao-jian Yi
Keyword(s):  
Complex Systems ◽  
Design Parameter ◽  
Design Method ◽  
Solution Space ◽  
Maximum Size ◽  
Design Criterion ◽  
Design Parameters ◽  
Engineering System ◽  
Output Performance ◽  
Maximum Solution

The uncertainty of the engineering system increases with the growing complexity of the engineering system; therefore, the tolerance to the uncertainty is essential. In the design phase, the output performance should reach the design criterion, even under large variations of design parameters. The tolerance to design parameter variations may be measured by the size of a solution space in which the output performance is guaranteed to deliver the required performance. In order to decouple dimensions, a maximum solution hyperbox, expressed by intervals with respect to each design parameter, is sought. The proposed approach combines the metaheuristic algorithm with the DIRECT algorithm where the former is used to seek the maximum size of hyperbox, and the latter is used as a checking technique that guarantees the obtained hyperbox is indeed a solution hyperbox. There are three advantages of the proposed approach. First, it is a global search and has a considerable high possibility to produce the globally maximum solution hyperbox. Second, it can be used for both analytically known and black-box performance functions. Third, it guarantees that any point selected within the obtained hyperbox satisfies the performance criterion as long as the performance function is continuous. Furthermore, the proposed approach is illustrated by numerical examples and real examples of complex systems. Results show that the proposed approach outperforms the GHZ and CES-IA methods in the literature.

scholarly journals Solving the Complexity Problem in the Electronics Production Process by Reducing the Sensitivity of Transmission Line Characteristics to Their Parameter Variations

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Talgat R. Gazizov ◽  
Indira Ye. Sagiyeva ◽  
Sergey P. Kuksenko
Keyword(s):  
Transmission Line ◽  
Production Process ◽  
Transmission Lines ◽  
Unit Length ◽  
Characteristic Impedance ◽  
Optimal Choice ◽  
Wide Range ◽  
Complexity Problem ◽  
Parameter Variations ◽  
Parameter Values

In this paper we consider the complexity problem in electronics production process. Particularly, we investigate the ways to reduce sensitivity of transmission line characteristics to their parameter variations. The reduction is shown for the per-unit-length delay and characteristic impedance of several modifications of microstrip transmission lines. It can be obtained by means of making an optimal choice of parameter values, enabling proper electric field redistribution in the air and the substrate. To achieve this aim we used an effective simulation technique and software tools. Taken together, for the first time, they have allowed formulating general approach which is relevant to solve a wide range of similar tasks.

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