ANALISA HEAD LOSSES DENGAN PENERAPAN SIMULASI PADA DIAMETER PIPA DAN PENGARUH NILAI NET POSITIVE SUCTION HEAD TERHADAP TERBENTUKNYA KAVITASI PADA POMPA

Pompa bekerja dengan mengkonversi energi mekanik menjadi energi kinetic dimana sepanjang aliran fluida akan mengalami kerugian aliran yang menyebabkan penurunan tekanan dorong di sisi discharge pompa. Hal ini disebabkan karena gesekan fluida dengan dinding pipa, dan penggunaan elbow, valve, dan lain-lain. Analisa ini bertujuan untuk menghitung besarnya kerugian tekanan (head losses) pada luas penampang pipa, Nett Positive Suction Head yang tersedia (NPSHa), dan pada akhirnya akan dibandingkan dengan Nett Positive Suction Head yang diperlukan (NPSHr) dari pompa. Hasil penelitian diperoleh kecepatan aliran pada pipa hisap dan tekan adalah 0,8567 , bilangan Reynold untuk pipa 4” adalah 295050 m (aliran turbulen), relative pipe Roughness untuk pipa 4” adalah 0,0015, kerugian pada pipa hisap sebesar 0,1082 m, kerugian pada pipa tekan 0,0927 m, kerugian head pada sambungan pipa elbow 900 sebesar 0,0012 m Kerugian head pada hambatan gate valve sebesar 0,0059 m.

The design of a novel arthroscopy shaver

Background: Cases of arthroscopic surgery have increased over the past two decades, and arthroscopic shaver systems have become a commonly used orthopedic tool. Nevertheless, most shavers generally have problems such as the cutting edge is not sharp enough and easy to wear. Design and validation: This paper aims to discuss the structural characteristics of BJKMC’s (Bojin◊ Kinetic Medical) novel arthroscopic shaver, the double serrated blade. The product's design and verification process are outlined. BJKMC’s articular arthroscopy shaver has a “tube in a tube” structure, comprising a stainless steel outer sleeve and a rotating hollow inner tube. The outer sleeve and inner tube have corresponding suction and cutting windows, and there are serrated teeth on the inner and outer casing. To verify the design rationality, it was compared to Dyonics◊’s equivalent product, the Incisor◊ Plus Blade. The appearance, cutting tool hardness, metal pipe roughness, cutting tool wall thickness, tooth profile, and angle, overall structure, and the key dimensions were examined and compared.Conclusion: Compared with Dyonics◊’s Incisor◊ Plus Blade, BJKMC’s Double Serrated Blade had a smoother working surface, harder and thinner blade head. Therefore, BJKMC’s product may have satisfactory performance when it comes to surgery.

Optimal architecture for artificial neural networks as pressure estimator

ABSTRACT The knowledge of hydraulic parameters in water distribution networks can indicate problems in real time, such as pipe bursts, small leakages, increase in pipe roughness and illegal connections. However, an accurate indication relies on the quantity and quality of the data acquired, i.e., the number of sensors used to monitor the network and their location. It is not economic feasible have a great number of sensors, thus, the use of artificial intelligence, such as Artificial Neural Networks (ANNs) can reduce the lack of information necessary to identify problems, estimating hydraulic parameter through the few information collected. The reliability of ANNs depends on its architecture, so, in this paper, different conditions are tested for ANN training to identify which are the most relevant parameters to be adjusted when the ANN is used for pressure estimation.

The Design of a Novel Arthroscopy Shaver

Background: Cases of arthroscopic surgery have increased over the past two decades, and arthroscopic shaver systems have become a commonly used orthopedic tool. Nevertheless, most shavers generally have problems such as the cutting edge is not sharp enough and easy to wear. Design and validation: This paper aims to discuss the structural characteristics of BJKMC’s (Bojin◊ Kinetic Medical) novel arthroscopic shaver, the double serrated blade. The product's design and verification process are outlined. BJKMC’s articular arthroscopy shaver has a “tube in a tube” structure, comprising a stainless steel outer sleeve and a rotating hollow inner tube. The outer sleeve and inner tube have corresponding suction and cutting windows, and there are serrated teeth on the inner and outer casing. To verify the design rationality, it was compared to Dyonics◊’s equivalent product, the Incisor◊ Plus Blade. The appearance, cutting tool hardness, metal pipe roughness, cutting tool wall thickness, tooth profile, and angle, overall structure, and the key dimensions were examined and compared. Conclusion: Compared with Dyonics◊’s Incisor◊ Plus Blade, BJKMC’s Double Serrated Blade had a smoother working surface, harder and thinner blade head. Therefore, BJKMC’s product may have satisfactory performance when it comes to surgery.

Estimation of Hydraulic Gradient for a Transport Pipeline

This work deals with the hydraulic gradient estimation in real-time of a transport pipeline computational model by considering a slightly compressible fluid and slightly deformable conduit walls. Since the hydraulic gradient (J(Q)) caused by the friction phenomenon in a pipeline plays an important role in the system's behavior, and this function is affected by fluid properties' deviations, environmental disturbances and conduit deteriorations, it is proposed that the on-line estimation of J(Q) could be part of a monitoring system. The proposition can be applied to obtain computational models of a line with a junction and assumes only measurements of pressure and flow rate at the ends of the conduit and the junction outflow. The generic form of the gradient function J(Q) is a second-order polynomial with coefficients that involve indirectly pipe roughness, the transversal area of the conduit, fluid viscosity and elements connected to the line. The extended Kalman filter (EKF) is applied to estimate the coefficients of the function J(Q). As a test apparatus, a 163 m long hydraulic pipeline is used. Diverse experiments show the usefulness of the on-line estimation of J(Q) for monitoring and simulation tasks where computational models are necessary.