An Experimental Study of Coefficient of Discharge for Consistent Hole Perforating and the Effect on Limited Entry Designs

2021 ◽  
Author(s):  
Scott Thiessen ◽  
Oliver Han ◽  
Ramadan Ahmed ◽  
Rida Elgaddafi
Keyword(s):  
Experimental Methodology ◽  
Critical Parameters ◽  
Single Shot ◽  
Unknown Variable ◽  
Before And After ◽  
Limited Entry ◽  
Actual Field ◽  
Flow Through ◽  
Coefficient Of Discharge ◽  
The Given

ABSTRACT In hydraulic fracturing, determining the perforation pressure loss is a critical step in the design strategy, on-site troubleshooting diagnostics and post-fracture analysis. Historically, the most widely assumed and thus unknown components in the perforation friction equationare the coefficient of discharge and the holistic perforation diameter. The perforation coefficient of discharge has long been assumed as a dynamic variable dependent on the amount of fluid and proppant pumped through the perforations. This variable becomes increasingly important when clusters are spaced closer together and fewer perforations are shot such as in a limited entry design. Limited entry is a perforating technique used to generate uniform fractures along the wellbore by creating appropriate pressure differentials from cluster to cluster. With the adoption of consistent hole perforating shaped charges, the perforating diameters are more consistent and predictable. While not all consistent hole shaped charges have low diameter variability, the perforating diameters downhole are no longer an unknown, particularly after the introduction of downhole cameras. Therefore, the coefficient of discharge is the only unknown variable remaining. This paper presents an experimental methodology to accurately define the true coefficient of discharge in common completions perforated by a known consistent hole shaped charge. The test setup is illustrated, detailed test steps are discussed, and experimental data with correlations of rate per perforation and discharge coefficient is presented. Completions tested included 4-1/2", 5", and 5-1/2" casings in common weights and grades. Various perforating strategies were examined such as single shot and angled shot. Critical parameters such as entry hole diameters were made by the actual shaped charges and measured before and after the test. Freshwater and slickwater were used as hydraulic fluid and circulated at real-world pump rates through each perforation to simulate the actual field flow conditions. Based on the study, several correlations for the coefficient of discharge of flow through a perforation are created considering casing thickness, entry hole diameter and rate per perforation for the given consistent hole shaped charges. These correlations can improve perforation and fracturing designs where perforation friction are important variables.

Heat Power Determination of Dv-290 Refrigerator’s Evaporator on the Basis of Thermodynamic Parameters of Inlet Air / Określenie Mocy Cieplnej Parownika Chłodziarki Dv-290 Na Podstawie Parametrów Termodynamicznych Powietrza Wlotowego

2012 ◽  
Vol 57 (4) ◽  
pp. 911-920
Author(s):  
Bernard Nowak ◽  
Zbigniew Kuczera
Keyword(s):  
Thermodynamic Parameters ◽  
Thermal Power ◽  
Correlation Coefficients ◽  
Specific Humidity ◽  
Physical Parameters ◽  
Air Cooling ◽  
Regression Equations ◽  
Evaporation And Condensation ◽  
Before And After ◽  
The Given

Abstract The present paper introduces a method for calculating the thermal power of DV-290 mining air cooler’s evaporator. The power usually differs from the nominal power given by the manufacturer. The thermodynamic parameters of cooled air are not obtained as a result of in situ measurements, but in indirect manner that is by determining the evaporation and condensation’s pressure values of R407C refrigerant. The pressure dependencies formulated as a function of air enthalpy at the evaporator’s inlet were obtained using calculations of a computer program which solves the system of equations describing heat and mass transfer in the refrigerator’s compressor on the basis of previous measurements of air performed before and after its cooling. The obtained dependencies are demonstrated in a graphical (fig. 2 and fig. 3) and analytical (the regression equations (19) and (20)) manner, the values of correlation coefficients are also presented. For the known evaporation and condensation pressure values of the refrigerant, and thus for its basic physical parameters the complete thermal power of the evaporator was determined, that is its: air cooling overt power, dehumidification occult power, temperature, relative humidity and specific humidity of air after its cooling. In addition, using the mentioned method, the capacity of DV-290 refrigerator’s evaporator is provided for the given thermodynamic parameters of air before cooling, along with air thermodynamic parameters after cooling.

scholarly journals Characterization and Identification of Varnishes on Copper Alloys by Means of UV Imaging and FTIR

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 298
Author(s):  
Miriam Truffa Giachet ◽  
Julie Schröter ◽  
Laura Brambilla
Keyword(s):  
Copper Alloys ◽  
Analytical Techniques ◽  
Experimental Methodology ◽  
Artificial Ageing ◽  
Non Invasive ◽  
Uv Imaging ◽  
Before And After ◽  
The Comparative Study ◽  
The 19Th Century ◽  
Analytical Tools

The application of varnishes on the surface of metal objects has been a very common practice since antiquity, both for protective and aesthetic purposes. One specific case concerns the use of tinted varnishes on copper alloys in order to mimic gilding. This practice, especially flourishing in the 19th century for scientific instruments, decorative objects, and liturgical items, results in large museum collections of varnished copper alloys that need to be preserved. One of the main challenges for conservators and restorers deals with the identification of the varnishes through non-invasive and affordable analytical techniques. We hereby present the experimental methodology developed in the framework of the LacCA and VERILOR projects at the Haute École ARC of Neuchâtel for the identification of gold varnishes on brass. After extensive documentary research and analytical campaigns on varnished museum objects, various historic shellac-based varnishes were created and applied by different methods on a range of brass substrates with different finishes. The samples were then characterized by UV imaging and infrared spectroscopy before and after artificial ageing. The comparative study of these two techniques was performed for different thicknesses of the same varnish and for different shellac grades in order to implement an identification methodology based on simple non-invasive examination and analytical tools, which are accessible to conservators.

Shell Body Nose Forming by Rotary Swaging Process

2011 ◽  
Vol 213 ◽  
pp. 221-225 ◽  
Author(s):  
Jeong Hwan Jang ◽  
Byeong Don Joo ◽  
Sung Min Mun ◽  
Young Hoon Moon
Keyword(s):  
Finite Element ◽  
Initial Thickness ◽  
Dimensional Changes ◽  
Rotary Swaging ◽  
Inside Diameter ◽  
Before And After ◽  
Forming Characteristics ◽  
Inner Diameter ◽  
The Given ◽  
Diameter Reduction

Studies on the forming characteristics by a rotary swaging process using the sub-scale specimens have been carried out to obtain a shell body nose of desirable quality. To analyze the changes of the nose thickness and length at the respective reduction of inside diameter, the finite element simulations were carried out. As a result, the desired target dimension is satisfied with the diameter reduction of more than 64 % for the given preform. The thickness of nose area increased up to 56.1 % from initial thickness of 2.62 mm to 4.09 mm after swaging. The values of the hardness before and after swaging were 208 HV and 325 HV, respectively. To analyze the dimensional changes (length and thickness) of nose area with decreasing inside diameter, the rotary swaging test was carried out for two different diameter reductions such as 65 % and 67 %. The lengths of nose area for the diameter reductions are 11.79 mm in 65 % and 12.53 mm in 67 %, respectively. At the diameter reduction of more than 67%, the crack occurs when the localized strain hardening reduces ductility in internal area. Therefore, the nose area should be formed from 64% to 67% reduction in target inner diameter.

Hemodynamic Method to Predict Whether Hunterian Ligation of the Basilar Artery Will Lead to Thrombosis of Basilar Bifurcation Aneurysms

Neurosurgery ◽  
1987 ◽  
Vol 20 (2) ◽  
pp. 249-253 ◽  
Author(s):  
Jack Chang ◽  
Margot R. Roach
Keyword(s):  
Pressure Gradient ◽  
Basilar Artery ◽  
Diameter Ratio ◽  
Phase Lag ◽  
Maximal Width ◽  
Before And After ◽  
Simple Measurement ◽  
Flow Through ◽  
Stop Flow

Abstract In some cases, basilar artery aneurysms cannot be repaired surgically and the basilar artery is occluded near the neck of the aneurysm to stop flow into the aneurysm. After the operation, the aneurysm can fill only by flow through the posterior communicating arteries (PCoAs). Hemodynamically, if the flow were the same in both PCoAs and there were no phase lag in the pressures, there would be no pressure gradient for flow to go across the neck of the aneurysm and therefore the aneurysm would thrombose. We have assumed that the diameter of the artery is roughly proportional to the flow that goes through it chronically. We measured the diameters of the PCoAs in 25 patients who had hunterian ligation of the basilar artery. We also measured the maximal width, height, and depth of the aneurysms on angiograms obtained before and after operation. Eleven aneurysms thrombosed completely and had a diameter ratio of > 0.6; 10 aneurysms thrombosed partially and had a diameter ratio of 0.46 ˜ 1.0; 4 aneurysms did not change and had a diameter ratio of <0.45. The ratio of the sizes of the PCoAs pre- and postoperatively was comparable in most cases, so we believe that it is possible to predict reasonably accurately from this simple measurement whether the aneurysm is likely to thrombose if the basilar artery is ligated.

POLICY OF PROMOTING ALCOHOL CONSUMPTION IN TIMES OF COVID-19 LOCKDOWN IN INDIA: A MEDICAL AND CONSTITUTIONAL ANALYSIS.

2021 ◽  
pp. 21-24
Author(s):  
Neha Sharma ◽  
Ayush Anand ◽  
Shreyas Joshi ◽  
Samrat Ray
Keyword(s):  
Mobile Application ◽  
Prospective Observational Study ◽  
Social Contact ◽  
Contact Tracing ◽  
Family Welfare ◽  
Cumulative Number ◽  
Test Results ◽  
Before And After ◽  
The Given ◽  
Constitutional Analysis

BACKGROUND: India, with the declaration of COVID-19 as a pandemic, started imposing restrictions in the country th and initiated a nationwide lockdown under Section 6 of the Disaster Management Act, 2005 on 24 March 2020, followed by four phases of lockdown and then gradual unlock of the country. The rationale behind the same was to avoid social contact. Alcohol dispensing was also stopped during this time and was among the rst services to be reopened by the States. We propose in this paper that this lifting of ban on alcohol sale during the pandemic has led to a signicant increase in the number of COVID-19 cases in the country. METHODS: This is a prospective, observational study, done by collecting data from the Aargya Setu App, which is a mobile application launched by the Ministry of Health and Family Welfare on 2 April 2020 for contact tracing and elf assessment of COVID-19. The data of cumulative number of cases in 12 selected states of the country were compared before and after the lift of ban of alcohol and signicance was shown by the paired t test. RESULTS: The number of COVID-19 positive cases in the country during nationwide lockdown with simultaneous ban on alcohol sale when compared to cumulative number of cases after the lift of ban of alcohol sale during Lockdown and initial Unlock is statistically signicant (p = 0.04) CONCLUSION: We found that the decision to restart the sale of Alcohol could have been a factor for rise in number of cases in the country in the given timeframe. The decision to start the sale has also not been in accordance with the Indian Constitution and against the nation's founding ethics.

scholarly journals An Experimental Methodology to Evaluate the Rigidity of Penile Prostheses in Vitro

2000 ◽  
Author(s):  
Shyh-Jen Wang
Keyword(s):  
Penile Prosthesis ◽  
Mechanical Failure ◽  
Experimental Methodology ◽  
Prosthetic Material ◽  
Mechanical Measurement ◽  
Hardness Tester ◽  
Non Invasive ◽  
Penile Prostheses ◽  
Before And After

Abstract This work investigates the hardness and buckling force of penile prosthesis to further understand the rigidity of penile prosthesis before and after implantation. Evaluated herein are four prosthetic samples (inflatable 3, semi-rigid 1), five realities (inflatable 1, semi-rigid 4), and one after implantation of prosthesis. The hardness is measured with a hardness tester by pressing the tester’s indentor to the surface of the specimen. In addition, a patient after implantation is evaluated with respect to the hardness of penile versus various numbers of pumping. The buckling force of the prosthesis is also determined by a push-pull gauge and special designed sampling table. Results in this study demonstrate that although the inflatable prosthesis could only be pumped to a certain amount of hardness, hardness and buckling force correlate well with each other. After reaching the extreme hardness, prostheses can even be further pumped a few times. However, continuous pumping only puts more tension on the prosthetic material without increasing any hardness and could induce to mechanical failure of prosthesis. Results also indicate that the buckling force decreases with increasing length of the semi-rigid prostheses, and, then, enlarged when the prosthesis has a larger diameter. This in vitro non-invasive mechanical measurement of the rigidity in penile prosthesis can provide not only clinicians with further information about the penile prosthesis before implantation, but also the patients with more confidence in the prosthesis usage after implantation.

scholarly journals Awareness on Drudgery Reducing Farm Technologies for Gender Equity

2020 ◽  
pp. 9-19
Author(s):  
V. Vijaya Lakshmi ◽  
J. Deepika
Keyword(s):  
Capacity Building ◽  
Gender Equity ◽  
Training Programme ◽  
Farm Women ◽  
Crop Season ◽  
Before And After ◽  
Seed Placement ◽  
Training Programmes ◽  
Adoption Level ◽  
The Given

Agriculture in India is moving away from animal driven to machine driven. Apart from tractors and power weeders which are used by farmers, there are farm tools and implements that can be used by farm women to reduce their drudgery with increased productivity. The present study made an attempt in introducing the set of 14 drudgery reducing farm tools and implements i.e. sapling transplanter, sickle/kurpi, long handle weeders, three types of harvest bags, ring cutter, finger guards, milking stand cum stool, head load manager, seed cum fertilizer bag, seed placement tube and fertilizer broad caster. A capacity building training programme was conducted to the farm women for exposure about the improved set of farm tools and implements. The implements were given to village secretary for use of this equipment by a group of 50 farm women and data were collected from them regarding the awareness about the technologies before and after the capacity building training programmes. Adoption levels were assessed after completion of a crop season. It was found that partial awareness was there about the improved equipment before training and cent per cent awareness was in the random selected group after the training programs. About 62 per cent of the sample has moderately adopted the given technologies. The study indicated for educating the farmers about the importance of drudgery reducing technologies, training them in using the farm implements and providing them to have an easy accessibility to enhance the adoption level. Custom hiring centres can be the solution to house the improved technologies suitable for farm women so that they can be used on rotation basis.

scholarly journals УТИЦАЈ КУРСЕВА ИЗ ЛОГИКЕ НА СТАВОВЕ СТУДЕНАТА

2021 ◽  
Vol 3 (1) ◽  
pp. 15-27
Author(s):  
Милан Јовановић
Keyword(s):  
Empirical Inquiry ◽  
Before And After ◽  
Students Attitudes ◽  
The Given ◽  
Do So

In this paper we survey and analyse the results from the project dedicated to the question – do logic courses influence students attitude concerning logic, and if they do, in which way? Our main prediction was that the logic courses do significantly influence relevant students’ beliefs, and that influence (or the change) varies depending on the theoretical direction of the course in question. The method of our empirical inquiry was test-based examination of students’ attitudes towards specific claims. We conduct the testing twice, before and after students have went through the relevant courses, and then compared the tests. Results, although different from hypothesis to hypothesis, do generally support the conclusion that logic courses influence relevant students’ beliefs, and they typically do so in accordance to the theoretical direction of the given courses syllabuses.

scholarly journals Penerapan Model Pembelajaran Kooperatif Tipe Teams Games Tournament untuk Meningkatan Hasil Belajar Siswa Kelas VI pada Mata Pelajaran Matematika di SDN No.058/XI Koto Dumo

2018 ◽  
Vol 18 (2) ◽  
pp. 355
Author(s):  
Zainal Abidin
Keyword(s):  
Cooperative Learning ◽  
Learning Outcomes ◽  
Descriptive Analysis ◽  
Sixth Grade ◽  
Sixth Graders ◽  
Learning Model ◽  
Sixth Grade Students ◽  
Before And After ◽  
The Given ◽  
Improve Student Learning

This study aims to improve the learning outcomes of sixth grade students at SDN. No. 058/XI Koto Dumo on mathematics subject, especially on integer operation material by using cooperative learning model of Teams Games Tournament type. This research is a classroom action research conducted in three cycles and each cycle is done with four activities, namely planning, implementation, observation, and reflection. This study was conducted from August to November of 2016. The study involved 16 sixth graders. Data were collected by observation and test. Data were analyzed by using descriptive analysis and simple statistical test. The results showed that the activities and learning outcomes of students before and after the given action (Cycle I, Cycle II, and Cycle III) improved. Thus, the use of cooperative learning model type Teams Games Tournament in SDN. No. 058/XI Koto Dumo can improve student learning outcomes in mathematics subjects, especially on the subject matter of integer counting operations.

scholarly journals Pengaruh Pemberian Buah Pisang Mas Terhadap Peningkatan Kadar Hb Pada Ibu Hamil Trimester III

2019 ◽  
Vol 5 (2) ◽  
pp. 50-54
Author(s):  
Elsa Kumala Safitri ◽  
Miftahul Mualimah ◽  
Herliana Riska
Keyword(s):  
Data Analysis ◽  
Pregnant Women ◽  
Blood Cells ◽  
Research Method ◽  
Observation Data ◽  
Banana Fruit ◽  
Signed Rank ◽  
Before And After ◽  
Protein Rich ◽  
The Given

Hemoglobin is a protein-rich substance bezi, Have affinity (power team) against oxygen and with oxygen it forms a oxihemoglobin in red blood cells. The goal in this research is to know the influence of banana fruit mas to increased hemoglobin on pregnant women trimester III in BPM Ny "B" Ngasem Regency Kediri Year 2017. In this research method using alphabets experiment and approach Pre alphabets experiment with Purposive Sampling. This research was conducted in BPM Ny "B" Ngasem Regency Kediri Year 2017. Instruments in use are sheets of observation, data analysis with the iji Wlcoxon Signed Rank. Results of research of banana fruit mas on pregnant women this trimester III that the magnitude of the value of ρ is less than the value of 0.000 α = 0.05 (0.000 < 0.05) so that H0 is rejected and the H1 is accepted means there is influence of hemoglobin levels before and after the given bananas mas against peningktan the levels of haemoglobin in pregnant women Trimester III in BPM Ny. " B “ Ngasem Regency Kediri year 2017. With this expected to consume fruit banana mas on pregnant women may help lower III trimester anemia with practical.

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