Shipbuilding -- Engine-room ventilation in diesel-engined ships -- Design requirements and basis of calculations

Construction navale -- Ventilation du compartiment machines des navires à moteurs diesels -- Exigences de conception et bases de calcul

General Information

Status
Published
Publication Date
06-May-1998
Current Stage
6060 - International Standard published
Start Date
23-Feb-1998
Completion Date
07-May-1998
Ref Project

RELATIONS

Buy Standard

Standard
ISO 8861:1998 - Shipbuilding -- Engine-room ventilation in diesel-engined ships -- Design requirements and basis of calculations
English language
14 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (sample)

INTERNATIONAL ISO
STANDARD 8861
Second edition
1998-05-15
Shipbuilding — Engine-room ventilation in
diesel-engined ships — Design
requirements and basis of calculations
Construction navale — Ventilation du compartiment machines des navires à
moteurs diesels — Exigences de conception et bases de calcul
Reference number
ISO 8861:1998(E)
---------------------- Page: 1 ----------------------
ISO 8861:1998(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide
federation of national standards bodies (ISO member bodies). The work of
preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which
a technical committee has been established has the right to be represented
on that committee. International organizations, governmental and non-
governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 8861 was prepared by Technical Committee
ISO/TC 8, Ships and marine technology, Subcommittee SC 3, Piping and
machinery.
This second edition cancels and replaces the first edition (ISO 8861:1988),
of which it constitutes a technical revision.
Annex A of this International Standard is for information only.
© ISO 1998

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced

or utilized in any form or by any means, electronic or mechanical, including photocopying and

microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet central@iso.ch
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
---------------------- Page: 2 ----------------------
INTERNATIONAL STANDARD ISO ISO 8861:1998(E)
Shipbuilding — Engine-room ventilation in diesel-engined
ships — Design requirements and basis of calculations
1 Scope

This International Standard specifies design requirements and suitable calculation methods for

the ventilation of the engine room in diesel-engined ships, for normal conditions in all waters.

Annex A provides guidance and good practice in the design of ventilation systems for ships'

engine rooms.

NOTE — Users of this International Standard should note that, while observing the requirements of the

standard, they should at the same time ensure compliance with such statutory requirements, rules and

regulations as may be applicable to the individual ship concerned.
2 Normative references

The following standards contain provisions which, through reference in this text, constitute

provisions of this International Standard. At the time of publication, the editions indicated were

valid. All standards are subject to revision, and parties to agreements based on this Interna-

tional Standard are encouraged to investigate the possibility of applying the most recent

editions of the standards listed below. Members of IEC and ISO maintain registers of currently

valid International Standards.
Quantities and units — Part 1: Space and time
ISO 31-1:1992, .
ISO 31-3:1992, Quantities and units — Part 3: Mechanics.
ISO 31-4:1992, Quantities and units — Part 4: Heat.
Reciprocating internal combustion engines — Performance — Part 1:
ISO 3046-1:1995,

Standard reference conditions, declarations of power, fuel and lubricating oil consumptions, and

test methods
ISO 3258:1976, Air distribution and air diffusion — Vocabulary.
3 Definitions

For the purposes of this International Standard, the definitions given below, together with those

in ISO 31-1, ISO 31-3, ISO 31-4, ISO 3046-1 and ISO 3258, apply.

3.1 engine room: Space containing main propulsion machinery, boiler(s), diesel generator(s)

and major electrical machinery, etc.
---------------------- Page: 3 ----------------------
ISO 8861:1998(E) ISO

3.2 ventilation: Provision of air to an enclosed space to meet the needs of the occupants

and/or the requirements of the equipment therein.
: The continuous brake power which the engine manufacturer
3.3 service standard power

declares that an engine is capable of delivering, using only the essential dependent auxiliaries,

between the normal maintenance intervals stated by the manufacturer and under the following

conditions:

a) at a stated speed at the ambient and operating conditions of the engine application;

b) with the declared power adjusted or corrected as determined by the manufacturer to the

stated ambient and operating conditions of the engine application;
c) with the maintenance prescribed by the engine manufacturer being carried out.
[ISO 3046-1:1995]
See A.1 in annex A of ISO 3046-1:1995.
4 Design conditions
The outside ambient air temperature shall be taken as + 35 °C.

Temperature rise from air intake to air passing from the engine room up to the casing entrance

shall be max. 12,5 K.

The capacity of the ventilation plant should be such as to provide comfortable working

conditions in the engine room, to supply the necessary combustion air to the diesel engine(s)

and boiler(s), and to prevent heat-sensitive apparatus from overheating.

In order to meet these requirements, the air should be distributed to all parts of the engine

room, so that pockets of stagnant hot air are avoided. Special considerations should be given to

areas with great heat emission and to all normal working areas, where reasonably fresh and

clean outdoor air should be provided through adjustable inlet devices.

When arranging the air distribution, all normal conditions at sea and in harbour for in-service

machinery shall be taken into account.
5 Airflow calculation
5.1 Total airflow

The total airflow Q to the engine room shall be at least the larger value of the two following

calculations.
Q q q
a: = + as calculated according to 5.2 and 5.3 respectively.
c h
Q q

b: = 1,5 x , i.e. the airflow for combustion + 50 %. The total airflow to the engine room

shall not be less than the airflow for combustion [engine(s) and boiler(s)] plus 50 %.

---------------------- Page: 4 ----------------------
ISO ISO 8861:1998(E)

Combustion air to, and heat emission from, all equipment installed within the casing and funnel

shall not be taken into account.

The calculations shall be based on simultaneous maximum rating of main propulsion diesel

engine(s), diesel generator engine(s), boiler(s) and other machinery under normal sea

conditions, and on a temperature increase of 12,5 K.

The calculations should, to the greatest possible extent, be based on information from the

manufacturers. Guidance values given in this International Standard should be used only when

manufacturers' information is not available.

In order to ensure satisfactory air distribution, combustion air to, and heat emission from, main

propulsion diesel engine(s), diesel generator engine(s), generator(s), boiler(s), and possibly

other machinery with considerable heat emission, shall be calculated separately including other

conditions as necessary.

Spaces separated from the main engine room, such as individual auxiliary engine rooms, boiler

rooms and separator rooms, shall also be calculated separately.
5.2 Airflow for combustion
5.2.1 Sum of airflow for combustion

The sum of the airflow for combustion, , shall be calculated, in cubic metres per second, as

follows:
q = q + q + q
c dp dg b
where

is the airflow for combustion for main propulsion diesel engine(s), in cubic metres

per second (see 5.2.2);

q is the airflow for combustion for diesel generator engine(s), in cubic metres per

second (see 5.2.3);

q is the airflow for combustion for boiler(s), in cubic metres per second (see 5.2.4), if

relevant under normal sea conditions.
5.2.2 Airflow for combustion for main propulsion diesel engine(s)

The airflow for combustion for the main propulsion diesel engine(s), q , shall be calculated, in

cubic metres per second, as follows:
×
P ad
q =
---------------------- Page: 5 ----------------------
ISO 8861:1998(E) ISO
where

P is the service standard power of the main propulsion diesel engine(s) at maximum

continuous power output, in kilowatts;

is the air requirement for combustion for diesel engine(s), in kilograms per kilowatt

second;

NOTE — Where specific data for m are not available, the following values may be used for

calculation:
m = 0,002 3 kg/(kW�s) for 2-stroke engines,
0,002 0 kg/(kW�s) for 4-stroke engines.
r = 1,13 kg/m (i.e. the density of air, at + 35 °C, 70 RH and 101,3 kPa).
5.2.3 Airflow for combustion for diesel generator engine(s)

The airflow for combustion for diesel generator engine(s), q , shall be calculated, in cubic

metres per second, as follows:
×
P ad
q =
where

P is the service standard power of the diesel generator engine(s) at maximum power

output, in kilowatts;

is the air requirement for diesel engine combustion, in kilograms per kilowatt second;

NOTE — Where specific data for are not available, the following values may be used for

calculation:
m = 0,002 3 kg/(kW�s) for 2-stroke engines,
0,002 0 kg/(kW�s) for 4-stroke engines.
r = 1,13 kg/m (i.e. the density of air, at + 35 °C, 70 % RH and 101,3 kPa).
5.2.4 Airflow for combustion for boilers and thermal fluid heaters

The airflow for combustion for boiler(s), , shall be calculated, in cubic metres per second, as

follows:

In a case where the total steam capacity of a boiler is known, the following formula is used:

---------------------- Page: 6 ----------------------
ISO ISO 8861:1998(E)
××
mm m
sfs af
q =

In a case where the capacity of a boiler or a thermal fluid heater is known in kilowatts, the

following formula is used:
Q××
fs af
q =
where
Q is the maximum continuous rating of the boiler(s), in kilowatts;

m is the total steam capacity (maximum continuous rating) of the boiler(s), in kilograms

per second;
is the fuel
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.