What do you mean by risers and downcomers, Mechanical Engineering

Assignment Help:

Q. What do you mean by Risers and Downcomers?

Risers and downcomers shall be staggered along the shell of the WHB and steam drum for uniform water/steam circulation in the system, taking into account the varying heat fluxes along the length of tubes. Film boiling (or dry-out) must be avoided in order to prevent tubes from destroying by deformity. The first pair of downcomers and the riser shall not be located further than 150 mm (6") form the inlet tubesheet. This distance of 150 mm is from the edge of the tubesheet to the nearest edge of the downcomer pipes.

The downcomer flow velocity shall be restricted to 1.52 m/s (5 ft/s). impingement plates, if provided shall not be welded to nozzle necks and tubes. Perforated plates are not acceptable.

The circulation of WHB system shall be computed for each circuit of downcomer and risers. A detail FEA shall be performed to predict water/steam circulation ratios. The FEA shall be based on an internationally recognized program, such as ANSIS or ALGOR and shall be submitted to WorleyParsons Canada for approval. Unsuitable programs, unacceptable to WorleyParsons Canada, shall be avoided.


Related Discussions:- What do you mean by risers and downcomers

Evaluate the heat input per day, The input-output curve of a 60 MW power st...

The input-output curve of a 60 MW power station is provided by : I = 10 6 [8 + 8L + 0.4L 2 ] Kcl/hour where I is the input in the Kcal/hour and L is the load in MW. (a) Ev

Factors affecting the selection of boiler, F AC T OR S AFFECTING THE SE...

F AC T OR S AFFECTING THE SELECTION OF BOILER: -     Working Pressure and amount of steam needed. -     Floor area required. -     Operating and Maintenance Required

Centre of gravity and centroid, Q.   Explain the terms centre of gravity an...

Q.   Explain the terms centre of gravity and centroid. Sol. : A point can be found out in a body through which resultant of all such parallel forces acts. This point through

Shear stress, write the assumption made in derivetion of shear stress produ...

write the assumption made in derivetion of shear stress produced in circular shaft subjected to torsion

Bell coleman cycle, Derive a formula for a bell coleman efficiency

Derive a formula for a bell coleman efficiency

Evaluate the chebyshev spacing for a function, Evaluate the chebyshev Spaci...

Evaluate the chebyshev Spacing for a function y = 2 x 2 - x for the range 0 ≤ x ≤ 2 where four precision point are required. For these precision points, determine φ 2 , φ 3 , φ 4

Machine design, The connecting rod of a four stroke cycle Diesel engine is ...

The connecting rod of a four stroke cycle Diesel engine is of circular section and of length 550 mm. The diameter and stroke of the cylinder are 150 mm and 240 mm respectively. The

Consider some publications of the bureau of standards, Consider some public...

Consider some publications of the Bureau of Standards. The following publications of the Bureau of Standards shall be read along with this section of footings. a. IS 456 in

What do you mean by weld and hold time, Q. What do you mean by Weld and hol...

Q. What do you mean by Weld and hold time? Weld time During this period the welding current flows through the circuit, i.e., it enters from one electrode, passes through t

What are the limitations with rectangular combined footings, What are the l...

What are the limitations with rectangular combined footings? In this section the analysis is limited to the determination of plan dimensions of the footing. The physical dimens

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd