Based on finite volume method, the pressure drop and heat transfer characteristics of one smooth tube and ten different axisymmetric corrugated tubes, including two with uniform corrugation and eight with non-uniform ...Based on finite volume method, the pressure drop and heat transfer characteristics of one smooth tube and ten different axisymmetric corrugated tubes, including two with uniform corrugation and eight with non-uniform corrugation, have been studied. A physical model of the corrugated tube was built, then the numerical simulation of the model was carried out and the numerical simulation results were compared with the empirical formula.The results show that: the friction factor decreases with the increase of Reynolds number ranging from 6000 to 57000, the value of which in the corrugated tubes with non-uniform corrugation(tube 03–10) are smaller than those with uniform corrugation(tube 01–02). The geometry parameters of tube(01) have advantages on the heat transfer enhancement in low Reynolds number flow region(from 6000 to 13000) and tube(07–08)have advantages on the heat transfer enhancement in high Reynolds number flow region(from 13000 to 57000). The vortex, existed in each area between two adjacent corrugations called second flow region, is the root of the enhancement on heat transfer in the corrugated tubes. The effectiveness factor decreases with the increasing of Reynolds number and the performances of the corrugated tubes with pitch of 12.5 mm have advantages than these of 10 mm under the same corrugation geometric parameter.展开更多
Pelvic fractures are serious injuries. Death within 24 hours is most often a result of acute blood loss. The emergency management of these patients is challenging and controversial. The key issues in its management ar...Pelvic fractures are serious injuries. Death within 24 hours is most often a result of acute blood loss. The emergency management of these patients is challenging and controversial. The key issues in its management are identifying the site（s） of hemorrhage and then controlling the bleeding. Management of hemodynamically unstable patients with pelvic fracture requires a multidisciplinary team. The issues addressed in this management algorithm are diagnostic evaluation, damage controlresuscitation, indications for noninvasive pelvic stabilization, preperitoneal pelvic packing and the critical decisions concerning surgical options and angiography. This review article focuses on the recent body of knowledge on those determinations.展开更多
Inferior glenohumeral dislocation is the least common type of glenohumeral dislocations. It may be associated with fractures of the adjacent bones and neurovascular compromise. It should be treated immediately by clos...Inferior glenohumeral dislocation is the least common type of glenohumeral dislocations. It may be associated with fractures of the adjacent bones and neurovascular compromise. It should be treated immediately by close reduction. The associated neuropraxia usually recovers with time. Traction-counter traction method is commonly used for reduction followed by immobilization of the shoulder for three weeks. Here, we report a case of inferior glenohumeral joint dislocation with greater tuberosity fracture with transient neurovascular compromise and present a brief review of the literature.展开更多
文摘Based on finite volume method, the pressure drop and heat transfer characteristics of one smooth tube and ten different axisymmetric corrugated tubes, including two with uniform corrugation and eight with non-uniform corrugation, have been studied. A physical model of the corrugated tube was built, then the numerical simulation of the model was carried out and the numerical simulation results were compared with the empirical formula.The results show that: the friction factor decreases with the increase of Reynolds number ranging from 6000 to 57000, the value of which in the corrugated tubes with non-uniform corrugation(tube 03–10) are smaller than those with uniform corrugation(tube 01–02). The geometry parameters of tube(01) have advantages on the heat transfer enhancement in low Reynolds number flow region(from 6000 to 13000) and tube(07–08)have advantages on the heat transfer enhancement in high Reynolds number flow region(from 13000 to 57000). The vortex, existed in each area between two adjacent corrugations called second flow region, is the root of the enhancement on heat transfer in the corrugated tubes. The effectiveness factor decreases with the increasing of Reynolds number and the performances of the corrugated tubes with pitch of 12.5 mm have advantages than these of 10 mm under the same corrugation geometric parameter.
文摘Pelvic fractures are serious injuries. Death within 24 hours is most often a result of acute blood loss. The emergency management of these patients is challenging and controversial. The key issues in its management are identifying the site（s） of hemorrhage and then controlling the bleeding. Management of hemodynamically unstable patients with pelvic fracture requires a multidisciplinary team. The issues addressed in this management algorithm are diagnostic evaluation, damage controlresuscitation, indications for noninvasive pelvic stabilization, preperitoneal pelvic packing and the critical decisions concerning surgical options and angiography. This review article focuses on the recent body of knowledge on those determinations.
文摘Inferior glenohumeral dislocation is the least common type of glenohumeral dislocations. It may be associated with fractures of the adjacent bones and neurovascular compromise. It should be treated immediately by close reduction. The associated neuropraxia usually recovers with time. Traction-counter traction method is commonly used for reduction followed by immobilization of the shoulder for three weeks. Here, we report a case of inferior glenohumeral joint dislocation with greater tuberosity fracture with transient neurovascular compromise and present a brief review of the literature.
