Mathematical and Experimental Investigation Into the Auto-Frettaging of High-Pressure Mudpump Fluid Ends

1978 ◽  
Vol 100 (1) ◽  
pp. 39-45 ◽  
Author(s):  
A. H. Van Der Krogt
Keyword(s):  
Experimental Study ◽  
Experimental Investigation ◽  
High Pressure ◽  
Fatigue Life ◽  
Mathematical Analysis ◽  
Operating Conditions ◽  
Plastic Behavior ◽  
Finite Element Approach ◽  
Element Approach ◽  
Internal Pressures

The fluid ends on high-pressure triplex mud pumps are exposed to high cyclic internal pressures. These fluid ends should therefore have adequate elastic strength and fatigue life under operating conditions. A method for increasing the fatigue life of the fluid ends is the auto-frettage process. The elastico-plastic behavior of fluid ends manufactured with side bores subjected to internal pressure has been studied both mathematically and experimentally. The mathematical analysis was carried out using an elasto-plastic finite-element approach. The experimental study, using direct strain-gage measurements, confirmed the mathematical analysis.

Experimental Investigation of Self-Excited Combustion Instabilities in a Lean, Premixed, Gas Turbine Combustor at High Pressure

2017 ◽  
Author(s):  
Timo Buschhagen ◽  
Rohan Gejji ◽  
John Philo ◽  
Lucky Tran ◽  
J. Enrique Portillo Bilbao ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
High Pressure ◽  
Operating Conditions ◽  
Chamber Pressure ◽  
Dynamic Mode ◽  
Combustion Instabilities ◽  
Compression Phase ◽  
Wide Range ◽  
Lower Amplitude ◽  
Lean Premixed

An experimental investigation of self-excited combustion instabilities in a high pressure, single-element, lean, premixed, natural gas dump-combustor is presented in this paper. The combustor is designed for optical access and is instrumented with high frequency pressure transducers at multiple axial locations. A parametric survey of operating conditions including inlet air temperature and equivalence ratio has been performed, which presents a wide range of peak to peak pressure fluctuations (p′) of the mean chamber pressure (pc). Two cases, Flame A and B with p′ /pc = 28% and p′/pc = 15% respectively, both presenting self-excited instabilities at the fundamental longitudinal (1L) mode of the combustion chamber, are discussed to study the coupling mechanism between flame-vortex interactions and the acoustic field in the chamber. OH*-chemiluminescence is used to obtain a map of global heat release distribution in the combustor. Phase conditioned analysis and Dynamic Mode Decomposition (DMD) analysis is performed, to highlight the contrasting mechanisms that lead to the two distinct instability regimes. Flame interactions with shear layer vortex structures just downstream of the dump plane during the compression phase of the acoustic cycle are found to augment the instability amplitude. Flame A engages strongly in this coupling, whereas Flame B is less affected and establishes a lower amplitude limit cycle.

scholarly journals Experimental Investigation of a High Pressure Ratio Aspirated Fan Stage

2004 ◽  
Author(s):  
Ali Merchant ◽  
Jack L. Kerrebrock ◽  
John J. Adamczyk ◽  
Edward Braunsheidel
Keyword(s):  
Experimental Investigation ◽  
High Pressure ◽  
Mass Flow ◽  
Pressure Ratio ◽  
Computational Prediction ◽  
Operating Conditions ◽  
High Pressure Ratio ◽  
Stage Performance ◽  
Design Speed ◽  
Computational Analyses

The experimental investigation of an aspirated fan stage designed to achieve a pressure ratio of 3.4:1 at 1500 feet/sec is presented in this paper. The low-energy viscous flow is aspirated from diffusion-limiting locations on the blades and flowpath surfaces of the stage, enabling a very high pressure ratio to be achieved in a single stage. The fan stage performance was mapped at various operating speeds from choke to stall in a compressor facility at fully simulated engine conditions. The experimentally determined stage performance, in terms of pressure ratio and corresponding inlet mass flow rate, was found to be in good agreement with the 3D viscous computational prediction, and in turn close to the design intent. Stage pressure ratios exceeding 3:1 were achieved at design speed, with an aspiration flow fraction of 3.5% of the stage inlet mass flow. The experimental performance of the stage at various operating conditions, including detailed flowfield measurements, are presented and discussed in the context of the computational analyses. The sensitivity of the stage performance and operability to reduced aspiration flow rates at design and off-design conditions are also discussed.

Thermal response of cylindrical tissue induced by laser irradiation with experimental study

2019 ◽  
Vol 30 (8) ◽  
pp. 4013-4023
Author(s):  
Aatef Hobiny ◽  
Ibrahim Abbas
Keyword(s):  
Experimental Study ◽  
Finite Element ◽  
Thermal Damage ◽  
Numerical Solutions ◽  
Thermal Relaxation ◽  
Bioheat Transfer ◽  
Living Tissue ◽  
Content Type ◽  
Finite Element Approach ◽  
Element Approach

Purpose The purpose of this paper is to provide a method for determining the numerical solutions of the thermal damage of cylindrical living tissues using hyperbolic bioheat model. Due to the complex governing equation, the finite element approach has been adopted to solve these problems. To approve the accuracy of the numerical solution, the numerical outcomes obtained by the finite element approach are compared with the existing experimental study. In addition, the comparisons between the numerical outcomes and the existing experimental data displays that the present mathematical models are efficient tools to evaluate the bioheat transfer in the cylindrical living tissue. Numerical computations for temperatures and thermal damage are presented graphically. Design/methodology/approach In this section, the complex equation of bioheat transfer based upon one relaxation time in cylindrical living tissue is summarized by using the finite element method. This method has been used here to get the solution of equation (8) with initial conditions (9) and boundary conditions (10). The finite element technique is a strong method originally advanced for numerical solutions of complex problems in many fields, and it is the approach of choice for complex systems. Another advantage of this method is that it makes it possible to visualize and quantify the physical effects independently of the experimental limits. Abbas and his colleagues [26-34] have solved several problems under generalized thermoelastic theories. Findings In this study, the different values of blood perfusion and thermal relaxation time of the dermal part of cylindrical living tissue are used. To verify the accuracy of the numerical solutions, the numerical outcomes obtained by the finite element procedure and the existing experimental study have been compared. This comparison displays that the present mathematical model is an effective tool to evaluate the bioheat transfer in the living tissue. Originality/value The validation of the obtained results by using experimental data the numerical solution of hyperbolic bioheat equation is presented. Due to the nonlinearity of the basic equation, the finite element approach is adopted. The effects of thermal relaxation times on the thermal damage and temperature are studied.

Experimental Investigation of Porous Bronze Bearings

1973 ◽  
Vol 95 (2) ◽  
pp. 173-179 ◽  
Author(s):  
C. Cusano ◽  
R. M. Phelan
Keyword(s):  
Experimental Study ◽  
Experimental Investigation ◽  
Coefficient Of Friction ◽  
Boundary Lubrication ◽  
Operating Conditions ◽  
The Coefficient Of Friction ◽  
Theoretical Analyses ◽  
Lubrication Conditions

An experimental study was made of the performance of porous bronze bearings under different operating conditions. A PV value of 50,000 psi ft/min was found to be too high for the assembly used when the bearings were lubricated only by the oil initially provided within their structure. Tests at a PV value of 33,000 psi ft/min gave satisfactory results. The coefficient of friction was found to vary with load and to be almost independent of speed for the bearings tested under boundary lubrication conditions. Except for relatively light loads and moderate and higher speeds, the bearings operate under boundary lubrication conditions. When pressurized oil was supplied to the bearings, it was found that, for the same operating conditions, porous bearings run at higher eccentricity ratios than solid bearings, as predicted by theoretical analyses.

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